# data[].attributes.headline
VNs role in pseudomonas otitis management and owner support

# data[].attributes.subject
VNs role in pseudomonas otitis management and owner support

# data[].attributes.body
Paterson, S. 2019. Pseudomonas otitis: what nurses need to know — frequently asked questions. The Veterinary Nurse [Online] Available from: < https://www.magonlinelibrary.com/doi/abs/10.12968/vetn.2019.10.4.189 > Accessed on 7.2.24

# data[].attributes.headline
Expertise of VN within the team for management of otitis, care interventions and cytology

# data[].attributes.subject
Expertise of VN within the team for management of otitis, care interventions and cytology

# data[].attributes.body
Paterson, s. et.al. 2021. Otitis externa: a roundtable discussion. Companion Animal [Online] Available from < https://www.magonlinelibrary.com/doi/full/10.12968/coan.2021.26.3.S1 > Accessed on: 7.2.24

# data[].attributes.headline
Pseudomonas as a common pathogen for otitis externa in dogs and indication for analgesia, antibiotics and surgical intervention

# data[].attributes.subject
Pseudomonas as a common pathogen for otitis externa in dogs and indication for analgesia, antibiotics and surgical intervention

# data[].attributes.body
Anderson, D. and Smith, J. 2020. Small animal surgical nursing. In: B. Cooper, E. Mullineaux and L. Turner, eds. 2020. BSAVA Textbook of Veterinary Nursing 6th edition. Gloucester: BSAVA. Chapter 23, page 820.

# data[].attributes.headline
Barrier nursing and isolation of contagious patients 

# data[].attributes.subject
Barrier nursing and isolation of contagious patients 

# data[].attributes.body
Bowes, V. 2020. Managing the hospital ward and basic patient care. In: B. Cooper, E. Mullineaux and L. Turner, eds. 2020. BSAVA Textbook of Veterinary Nursing 6th edition. Gloucester: BSAVA. Chapter 14, page 353.

# data[].attributes.headline
CoPC VN's professional responsibilities to patients, clients and the veterinary team

# data[].attributes.subject
CoPC VN's professional responsibilities to patients, clients and the veterinary team

# data[].attributes.body
RCVS, 2023. Code of professional conduct for Veterinary Nurses [Online] Available from < https://www.rcvs.org.uk/setting-standards/advice-and-guidance/code-of-professional-conduct-for-veterinary-nurses/#team > Accessed on: 7.2.24

# data[].attributes.attachment_link.title
Code of Professional Conduct for Veterinary Nurses

# data[].attributes.attachment_link.description
The RCVS Code of Professional Conduct for Veterinary Nurses is set out in full below - clicking the linked contents will drop down to the corresponding section. The supporting guidance may also be accessed using the menu.

# data[].attributes.body
Veterinary Sciences | Free Full-Text | Physiotherapeutic Strategies and Their Current Evidence for Canine Osteoarthritis (mdpi.com)

# data[].attributes.attachment_link.readable_text
In this review, the authors discuss the different levels of the pyramid (environmental modification, exercise plan, OA-specific home exercises and treatment by a veterinary physiotherapist) taking into account the current literature. To this end, evidence on the topics addressed below was collected using the databases Pubmed, Google scholar and PEDro without setting limits for date or type of publication. The results were taken into account weighted by the strength of evidence ranging from systematic reviews, RCTs, experimental studies to observational studies, but without considering mere individual opinions or subjective experience.

Physical medicine and rehabilitation physicists play a central role in human OA management, as arthritis education is considered essential for successful OA therapy [ 25]. Both home and group exercise are considered efficacious in people with hip and knee OA [ 23]. Based on a recent systematic review, cost efficacy has been shown for exercise interventions with or without education for human OA therapy [ 26]. There is evidence supporting individualized programs for the patient, and although the value of therapy from qualified therapists improves outcomes, they emphasize the value of regular home exercise and the importance of adherence to recommended programmes [ 18, 23, 27].

The primary role in devising management protocols for osteoarthritic patients usually lies with a first opinion veterinary practitioner, rather than a specialist in rehabilitation. Given the numerous PT modalities available, the relative paucity of literature and the amount of direct advertising of services to owners, this role may often be overwhelming, leading to suboptimal management programs. Practitioners feel unable to give clear advice on the relative priority of different modalities due to cost and effectiveness.

The Physiotherapy Pyramid ( Figure 1) has been devised to illustrate a systematic organized approach prioritizing simple measures as a foundation for success in a global approach to OA management. The available modalities have been broadly grouped into layers of the pyramid. Those thought to be more practical, cost-effective and beneficial are at the lower layers should be considered and implemented before those in the layers above-i.e., planning should start at the base of the pyramid, and then subsequently progress towards the top. Patient comfort needs to be taken into consideration throughout each step. Clinicians may then use this structure as a guideline to more confidently recommend modalities to the patient owner in a clear and ordered manner.

3.1. Pyramid Level I: Environmental Modification

Evidence for the benefits and methods of environmental modification in canine OA patients is still limited. Thus, recommendations are primarily based on experience and clinical judgement of the veterinary team and patient owner. Recommendations are currently tailored based on specific information on the individual patient and its immediate environment (both home and exercise areas), rather than on evidence-based protocols [ 44].

Independent locomotion is important for dogs, both from a rehabilitative and behavioural reasons [ 45]. In severely recumbent patients, or those with minimal ability to rise from rest, soft bedding is clearly recommended to avoid decubital ulceration [ 46]. Adjuncts such as support slings may be beneficial to aid the owner in helping the patient to rise and ambulate safely [ 47]. Osteoarthritic patients, due to their reduced muscle mass and reduction in joint proprioceptive receptors, are prone to slipping and often lose confidence in ambulation (or are prone to injury) if the flooring in their home environment does not provide good grip underfoot. Altering slippery floors (either replacing with carpet, or using rubber matting in areas the patient must access) can improve both confidence and ability to move safely within the home [ 44]. Raising the height of food and water bowls and using ramps to allow access over steps or into cars is also a straightforward adaptation that can improve mobility. Consideration may be given in the home to ensure that the patient is not forced to use steps or stairs to move between food, water, and rest areas. When outside, exercise areas should be chosen with good footing (such as grassland or parks) rather than rough ground, and softer more regular surfaces such as grass are to be preferred over hard and irregular ones (such as gravel, shingle or wet rocks), especially in patients with distal limb OA.

These changes are easily made, but often overlooked. Raising of owners' awareness by clinicians after questioning or inspection of the home environment may provide significant benefit to the patient complementary to pharmaceutical and PT regimes. As many owners with dogs suffering from osteoarthritis feel lost and not sufficiently supported by their veterinarians due to lack of time during appointments [ 9], implementing apps helping owners to optimize the home environment may prove useful.

3.2. Pyramid Level II: Exercise Regimen/Activity

OA is often interpreted as the result of "wear and tear" [ 48], leading to the belief that further exercise could worsen the problem. This statement is not true, and OA should be seen as a disease with a more complex, still not completely understood pathogenesis [ 49]. However, the important role of the cartilage is undisputed. Because its metabolism is only via diffusion through synovial fluid, movement is very important. It has been shown that a moderate running program (10 weeks, 1 h daily on a 15° uphill treadmill, 4 km/h) increases Glycosaminoglycans in the synovial fluid of the stifle in young beagles and thickening of the cartilage [ 50]. However, to the authors' knowledge, there is currently a lack of similar studies exploring the effects of walking over ground with differing velocity and duration on cartilage metabolism.

There are currently no studies exploring if dog sports such as agility or fly ball increase the risk of OA. The increased incidence of knee OA in human athletes seems to be the result of injuries, as a prospective study with long-distance runners (with follow-up over 20 years) showed no increased risk of knee OA [ 51]. A recent systematic umbrella review on the effects of physical activity in human knee and hip OA concluded that there is strong evidence that exercise decreases pain and improves function [ 52]. In addition, even 45 min per week of moderate-intensity activity is associated with improved function, with effects lasting up to 6 months. A second review assumes that there is no recommendable intensity for general human health benefits: everyone can improve by simply becoming more active, even with relatively minor volume [ 53]. Comparable studies in veterinary medicine are missing.

In veterinary medicine, the feasibility of an activity monitoring in 72 OA affected dogs was evaluated and rated as a helpful tool [ 54]. In addition, there was a negative correlation between activity level and body weight. An increased body weight is a well-known risk factor in development of canine OA and weight reduction leads to an improvement of the symptoms (especially lameness) [ 55, 56]. One important fact is the reduction of the load, but additional biochemical factors remain unclear: in obese humans, a pro-inflammatory effect [ 48] is reported (e.g., pro-inflammatory cytokines), but this could not be confirmed in dogs [ 57]. Whether hyperleptinemia, which is increased in obese dogs [ 58], is important for development of OA is unclear.

However, physical activity should be an important factor in OA management and applied with a patient-oriented intensity, regular frequency, and with low impact [ 59]. Considering the current paucity in the literature, over ground walking is assumed to provide adequate exercise in dogs with osteoarthritis. Often, a specialist is helpful to analyse the current activity level and customize the training to the severity of the OA condition [ 54]. Excessive activity, which leads to a worsening of the lameness, should be avoided.

3.3. Pyramid Level III: OA Specific Home Exercises

3.3.1. Introduction

3.3.2. Strengthening Exercises

Muscle weakness is a key symptom in osteoarthritic people and has been shown to be a predictor of knee OA onset [ 64, 65]. In people with OA, muscle weakness is leading to decreased proprioception and instability in human knees, and there is an increased risk of falling [ 66]. In people, physical exercise is considered the most frequently recommended non-pharmacologic treatment for OA [ 19]. Physical exercise not only has the potential to increase muscle strength, but has also been shown to improve proprioception and joint functionality [ 67]. In particular, strengthening is considered a core treatment for human OA [ 19], considering the pain reduction, improved physical function and quality of life that can be achieved [ 68, 69]. This is of even greater significance, as muscle strengthening programmes for knee OA have improved joint stability and were able to prevent joint dysfunction based on a six-year cohort study [ 70]. The clinical efficacy of strengthening exercises in osteoarthritic dogs has not been established yet but are recommended on a routine basis clinically and expected to play a key role in canine OA therapy [ 71, 72]. Strengthening exercises are tailored by the physiotherapist according to the affected osteoarthritic joint and the corresponding muscle weakness. The positive effect of muscle strengthening is expected to become only apparent after weeks to months and needs be maintained with ongoing training [ 72]. In dogs, resistance training is commonly utilized for strengthening with dogs working against their own weight (for example sit-to-stand exercise) or against additional stressors (for example elastic bands, or carpal weights) [ 73]. Regular walking is routinely recommended as exercise for osteoarthritic dogs to aid strength, aerobic capability and weight control [ 18, 21, 74, 75]. Walking on different terrains is an exercise that can be accomplished by most dogs and dog owners.

Depending on the gait phase, many different muscles are activated, both in the trunk and the limbs. Some muscles primarily stabilize (such as the supraspinatus and infraspinatus muscles in the stance phase) and others actively flex or extend [ 76, 77].

The walking exercise can also be adapted to the individual dog through variations such as slight inclines, which has shown to increase the hip joint flexion [ 78].

There is currently no evidence that the type of strengthening exercise by itself affects outcome in human OA patients significantly [ 19]. Nevertheless, human guidelines indicate that outcome can be optimized, when strengthening exercises are complemented by other exercises (for example ROM, stretching, functional balance and aerobic exercises). Consistent progression of strengthening is considered a "must" for therapeutic success [ 69]. These recommendations appear applicable to canine patients too.

3.3.3. Passive Range of Motion (ROM) Techniques

Controlled joint motion is considered vital for joint health [ 16]. The benefits of joint motion were first demonstrated by R.B. Salter and colleagues in the 1970s in experimental rabbit models comparing effects of continuous joint motion to joint immobilization after cartilage injury [ 79]. Since then, continuous passive motion (CPM) has been applied in people above all as adjunct therapy after articular surgery with the goal to improve cartilage healing and regeneration and decrease potential for post-traumatic arthritis [ 16, 80, 81]. For CPM, range of motion is applied to the joint by an automatic motor-driven device with the goal to allow for early joint movement without the patients needing to use their muscles. Continuous passive motion has been shown to stimulate proteoglycan 4 chondrocyte metabolism in healthy bovine joints [ 82], but studies specifically investigating the effect of CPM for osteoarthritic joints are scarce [ 83]. Clinically, CPM combined with thermo- and vibrational therapy has been shown to decrease pain in people with OA [ 83]. It remains unclear whether this effect is due to CPM itself. Clinically, CPM is currently not performed in dogs. However, a CPM related technique, namely passive range of motion (PROM), is very popular and frequently recommended as home exercise to be performed by owners in osteoarthritic dogs [ 84]. Passive ROM is the motion of a joint without contraction of a muscle through the available ROM [ 85]. Currently, there is no direct evidence for efficacy of PROM for OA management and benefits appear to be mainly extrapolated from CPM research. Stretching techniques are also utilized clinically in conjunction with ROM exercises with the goal to elongate shortened periarticular tissues in dogs with restricted joint ROM [ 85]. Passive stretching of osteoarthritic elbow, carpal and stifle joints performed by owners twice daily for 21 days improved joint range of motion [ 43]. Longevity of this effect is currently unknown.

Manual joint mobilization techniques require special training for the correct application and are not suitable for laymen. Throughout joint manipulation and stretching, elasticity of the joint capsule and periarticular musculature is improved. Manual joint therapy in the form of joint mobilizations has been shown to reduce pain, stiffness and dysfunction in people with OA, but efficacy in dogs has not been explored yet [ 86].

Simple passive joint movements [ 85] performed by physiotherapists or owners are not considered a core element in PT protocols for osteoarthritis, as they are not expected to improve muscle strength. Active exercises are definitely preferred over passive techniques and should be executed whenever possible and tolerated by the patient [ 19].

3.3.4. Proprioceptive and Balance Exercises

Balance and proprioceptive training has been shown to effect walking ability, balance, pain, stiffness and functionality positively in people with OA. The effect of balance and proprioceptive training techniques on osteoarthritic dogs has not been investigated yet. However, a recent pilot study training healthy agility dogs on a motorized imoove ® balance platform (Allcare Innovations, Bourg-lès-Valence, France) indicates enhanced body control, superior speed during agility trials and improved muscular mass [ 93] compared to the dogs' performance prior to the balance training. Further studies are needed to investigate whether and how dogs with OA may benefit from different proprioceptive and balance exercises. As these exercises can be easily implemented by owners at home, the authors propose that proprioceptive and balance exercises should remain components of home exercise protocols for dogs with OA until further evidence arises.

3.3.5. Massage

3.3.6. Aquatic Exercise

Patient owners may have access to lakes, rivers and oceans during the walks with their dogs. Recently, canine-specific pools have become accessible to dog owners for recreational, therapeutic and conditioning purposes too [ 99, 100]. Based on a recent questionnaire study, 18% of dogs undergoing hydrotherapy in hydrotherapy centres in the United Kingdom are treated for OA [ 100].

Current human guidelines recommend aquatic exercise for knee OA, dependent upon comorbidity status, but are not considered efficacious for patients with hip or polyarticular OA [ 22]. To the authors' knowledge, clinical efficacy of the different aquatic exercise forms for muscle strengthening has neither been investigated for healthy nor for osteoarthritic dogs. In one recent study, elbow joint ROM increased significantly in dogs with elbow OA after a 20 min swimming session in a pool, when evaluated 10 min after the session [ 107]. Long-term benefits of aquatic therapeutic interventions with regard to functionality, joint stiffness, comfort and ROM of osteoarthritic dogs have not been investigated yet.

3.4. Pyramid Level IV: Treatment by Physiotherapist

3.4.1. Role of a Physiotherapist in Treatment of Osteoarthritis

The physiotherapist's task as an expert is first to evaluate the patient and its environment, second to develop a treatment plan and third to integrate the plan into the patient's and its owner's daily life. The trend goes away from the physiotherapist as a kind of remedy applied to the patient, towards the physiotherapist as a consultant and expert. We should go from working "on" the patient towards working "with" the patient [ 108] and in veterinary medicine working with the owner too.

3.4.2. Physiotherapeutic Assessment in Canine OA

The physical effects of OA vary from patient to patient (body functions and structures) and are influenced by comorbidities and by daily activities (walking time, sport activities, owner's activity). Some limitations have an impact on daily life in which the dog can no longer participate as usual, e.g., jumping into the car. In addition, there are environmental factors, such as only being able to reach the home via stairs, which must be included in therapy planning and goals. Individual factors such as breed and age should also be mentioned. Special attention should be paid to the goals, resources, and compliance of the owner. Although numerous outcome measures are available for canine osteoarthritis [ 109], there is no suitable diagnostic tool addressing overall function and fitness in veterinary physiotherapy. We therefore propose to adopt and adapt the widely used human diagnostic tool called ICF ("International Classification of Functioning, Disability and Health"), established by the World Health Organization) for the use in canine OA. This assessment tool considers all aspects of functioning [ 110] in daily life (see Figure 2).

Based on this holistic functional assessment, the physiotherapist develops an individual exercise plan. In human medicine, supervised active treatment (exercises) is currently considered best practice [ 111] when physiotherapy is initiated in patients with knee and hip osteoarthritis. A minimum of 12 sessions are recommended (two per week) with active treatment progressing in intensity over time and development of a home-exercise program to obtain sufficient clinical benefit [ 111]. Fewer than 12 sessions are less effective among human knee OA patients [ 112]. Adjunct treatments such as electrotherapy are only recommended after this initial phase, if the patient's symptoms do not improve sufficiently.

Exercises must be performed correctly to be effective in OA patients. Therefore, regardless of the chosen exercise, it has to be prescribed appropriately [ 116] and as specifically as possible [ 117]. In veterinary medicine, the correct execution of exercises may be challenging, as concise oral instructions are difficult when working with canine patients. The supervising physiotherapist must identify incorrect movement patterns and needs to develop creative strategies, such as, for example, the sit-to-stand-exercise performed along a wall to prevent a lateral shift. Thus, patients may benefit from contact to a physiotherapist early in the course of OA, as at-home and multimodal management strategies can be optimized, even if routine physiotherapy visits are not needed yet.

As OA is a chronic and progressive disease, the patient needs lifelong support (e.g., by an exercise program). Therefore, in a holistic approach, the physiotherapist plays an important role in the periodical reassessment of the patient's condition changing over time. Thus, they ensure the adaption of the multidisciplinary treatment of OA, when necessary.

The term "therapeutic modalities" refers to the use of thermal, mechanical, electromagnetic, light or other energies with the goal to achieve specific therapeutic effects [ 118]. Numerous therapeutic modalities such as laser, cryo- and thermotherapy, extracorporeal shockwave, magnetic field, radiofrequency and electrotherapy have been recommended as adjunct measures to therapeutic exercises, manual therapy and patient owner education in dogs with osteoarthritis [ 12, 119, 120]. The majority of modalities are technically complex and need to be performed under direct supervision or personally by the physiotherapist. Simple cryo- and thermotherapeutic measures, which can be executed by the patient owner and magnetic field therapy, were beyond the scope of this review and are discussed elsewhere.

4.1. Low Level Laser Therapy (LLLT) in Osteoarthritis

The term LLLT refers to a painless non-invasive therapeutic modality, operating with near-infrared or infrared-light. In North America, LLLT is extremely popular for the therapy of canine OA and OA-related musculoskeletal disorders in veterinary practice [ 121, 122]. The annual economic impact of laser therapy for treatment of a single OA joint in dogs has been estimated to be approximately $6.2 million per year for one single Midwestern U.S. state [ 121]. This is remarkable, as therapeutic efficacy of LLLT for OA has not yet been clearly determined yet.

The therapeutic effects of LLLT for patients with OA are not completely understood, but analgesic and anti-inflammatory effects have been demonstrated in experimental settings. In a rat model of peripheral inflammation, LLLT induced an analgesic effect via enhancement of peripheral endogenous opioid production in inflamed tissues [ 123]. Furthermore, the analgesic effect is thought to be mediated by direct inhibition of peripheral nerves [ 124]. Based on a systematic literature review, LLLT slows conduction velocity, reduces amplitude of compound action potentials and suppresses electrically and noxiously evoked action potentials in mammalian nerves [ 124]. In several rat models of artificially induced OA [ 31, 125], laser therapy alone or combined with exercise promoted an anti-inflammatory effect due to improved microcirculation resulting in "wash out" of proinflammatory substances [ 125, 126]. Significant reduction of proinflammatory substances such as PGE2, IL-1β and TNF-α, has so far been only observed with tendon injuries and muscle inflammation [ 127]. However, this anti-inflammatory effect has not been demonstrated in OA models yet.

In veterinary medicine, evidence for LLLT's effectiveness in OA patients is still limited. One randomized blinded placebo-controlled trial [ 42] reported improved lameness scores and pain in dogs with naturally occurring elbow OA. In a retrospective study without control group, dogs with various affected OA joints responded positively to LLLT based on Canine Brief Pain Inventory (CBPI) and Visual Analogue Scale (VAS) scores. This positive effect was already observed after the first therapy session, but further improvement was observed with subsequent sessions. Analgesic medications could be reduced subsequently (see Table 1) [ 41].

In human medicine, the evidence base for therapeutic efficacy of LLLT for OA is better, but results are conflicting. Based on a recent Cochrane review evaluating seven controlled clinical LLLT trials in people with OA, evidence for LLLT's potential therapeutic effect is inconclusive and insufficient considering the contradictory results of these studies [ 128]. However, laser therapy did not cause any side effects in neither human nor veterinary OA patients.

Application modes differ in LLLT studies for human and veterinary OA. Due to differing laser mode (continuous vs. pulsed), wavelengths, dosage and site of application (over nerves versus joints), comparison between studies and extrapolation is difficult. In particular, wavelength is an important parameter with regard to tissue penetration. Wavelengths between 650 and 1350 nm have the lowest absorption by the main chromophores (water, melanin, hemoglobin) and thus the highest penetration depth into tissues [ 129]. Nevertheless, there is still a lack of knowledge on the optimal joint-specific wavelength for OA treatment.

4.2. Therapeutic Ultrasound

Therapeutic ultrasound (TU) is a therapeutic modality employing acoustic sound waves in a non-audible frequency range between 1-3 MHz [ 130]. Therapeutic ultrasound induces thermal (by friction) and non-thermal (micro massage) effects [ 131, 132]. Traditionally, TU's deep tissue warming effect has been utilized in dogs to treat OA induced muscle shortening and hypertonus [ 133]. Due to the short duration of its heating effect, TU is typically used immediately prior to or during stretching in dogs with OA [ 134].

Recent experimental studies on the underlying molecular and genetic mechanisms indicate that TU exhibits complex anti-inflammatory effects mediated by gene induction, immunosuppressor cell promotion, and enhancement of exosome biogenesis and docking, that may prove to be of therapeutic benefit in aseptic inflammatory diseases such as OA [ 135]. Promising cellular effects were observed in human osteoarthritic articular knee cartilage compared to untreated controls: increased expression of type II collagen and proteoglycan, decreased matrix metalloproteinase-13 expression and increased chondrocyte proliferation [ 136, 137]. Considering these effects, patients may also benefit from direct treatment of osteoarthritic joints.

In people, articular TU application has been shown to be a safe modality to reduce pain and to improve function in patients with knee OA, but this effect was only evaluated in a short time period between two weeks and one year [ 136]. A recent canine study indicated that TU may also be beneficial in dogs with OA. In an experimental canine stifle OA model (injections of sodium monoiodoacetate in the left knee, right joint served as control), effected joints were treated nine times with TU (3 MHz frequency, power density 1.20 W/cm ², pulsed wave duty cycle 1:2) [ 138]. Subsequently, improved synovial fluid viscosity, joint range of motion and muscle mass and increased loading on the affected limb were observed.

Evidence on therapeutic efficacy of selected TU mode (continuous versus pulsed), optimization of frequency, power density and dosing intervals for OA is still scarce. Findings on a recent systematic review and metanalysis indicated that pulsed TU may be more efficacious than continuous TU for pain control and improved function in people with knee OA [ 139]. Further controlled comparative studies are needed.

4.3. Extracorporeal Shock Wave Therapy

Extracorporeal shock wave therapy (ESWT) is a therapeutic modality employed to treat various musculoskeletal diseases including tendinous disorders, fasciitis, non-union of long bone fractures and avascular necrosis of the femoral head and osteoarthritis [ 140]. Shockwaves are highly energetic acoustic waves with very high-pressure amplitude and ultrashort duration. In veterinary medicine, focused and radial shockwave technologies have been employed for the treatment of OA [ 37, 38, 39, 40]. Focused shockwaves are generated by electrohydraulic, electromagnetic and piezoelectric devices based on shock wave lithotripter technology and unfold their highest energy density deep in the tissues [ 141, 142]. Radial shockwaves, on the other hand, are generated by ballistic devices and have a more superficial unfocussed effect on tissues with a decrease in energy in proportion to the square of the distance from the surface [ 39, 141].

Shockwaves are thought to provide mechanical stimuli resulting in biologic tissue effects. ESWT induced cellular alterations result from conversion of a mechanical signal into biochemical or molecular biologic signals (mechanotransduction) [ 143]. The mechanisms of action of ESWT have not been entirely understood yet, but the beneficial effect of shockwaves for OA therapy appears to be based on chrondroprotective and analgesic effects [ 140].

In early knee arthritis in rats, ESWT significantly reduced cartilage surface damage and proteoglycan loss, enhanced subchondral bone repair upon micro-CT evaluation and promoted cartilage proliferation [ 144]. Based on an experimental study in rabbits, ESWT lessened the progression of knee OA by reduction of nitric oxide level and chondrocyte apoptosis [ 32]. In an OA knee model in rats, ESWT showed a positive effect decreasing metalloproteinase and increasing type II collagen synthesis and anabolism, as well as blood flow to the subchondral bone in a number of treatment related manners [ 145]. Several experimental studies also showed ESWT induced neovascularization and upregulation of angiogenic and osteogenic growth factors (endothelial nitric oxide synthase, vascular endothelial growth factor, proliferating cell nuclear antigen, and human bone morphogenetic protein 2) in bone healing and tendinopathy models [ 146, 147].

The pathomechanism of ESWT's analgesic effect has not been completely elucidated yet. Hyperstimulation of nociceptors and the interruption of nerve impulses have been postulated to trigger an analgesic effect in patients with chronic pain [ 143]. Several studies point towards degeneration of nerve endings inhibiting the upward transmission of pain via sensory nerve fibers as ESWT's analgesic pathomechanism [ 148, 149]. Non-focused ESWT of the palmar digital nerves in horses decreased sensory nerve conduction velocities [ 150]. In this study, disruption of the myelin sheath with no evidence of damage to Schwann cell bodies or axons of the treated nerves was observed upon transmission electron microscopy. Thus, simultaneous ESWT of nerves adjacent to treated osteoarthritic joints may also contribute to ESWT induced analgesia [ 150]. Shockwaves may also ameliorate pain in osteoarthritic patients, as ESWT reduces the expression of calcitonin gene-related peptide in dorsal root ganglia, which play a role with sensation of joint pain [ 149, 151]. Some authors have theorized that the analgesic effect may be associated with ESWT induced enhancement of the microcirculation [ 152].

In prospective clinical studies, ESWT improved lameness upon objective gait analysis in dogs with elbow and hip OA, but not in dogs with stifle OA compared to the control groups (see Table 2) [ 37, 38, 39, 40]. Except for Souza et al.'s study on radial ESWT for hip osteoarthritis, these canine studies have pilot character due to lower patient numbers. Although focused ESWT improved PVF and VI in dogs with osteoarthritic elbows significantly compared to the control group, study duration was limited to 28 days and long-term therapeutic effects are still unknown [ 38]. Radial ESWT has been shown to benefit dogs with hip OA in 2 studies up to 3 and, respectively, 6 months [ 39, 40]. Nevertheless, evidence of Mueller et al.'s study is considered limited due to the low case number and the non-randomized and non-blinded study design [ 39, 153]. There is an obvious lack of studies investigating long-term effects, optimal dosing intervals, intensity and frequency for radial and focused ESWT for dogs with OA.

Although studies investigating clinical benefits of ESWT in osteoarthritic dogs are limited, numerous studies exploring therapeutic efficacy of ESWT in people with OA have been performed and systematic reviews and metanalyses are encouraging. A recent systematic review and metanalysis focused on the efficacy of ESWT for all types of human OA [ 154]. Based on this review, ESWT was superior in both pain reduction and functional improvement compared with placebo, corticosteroid, hyaluronic acid, medication and ultrasound [ 154]. In people with knee OA, ESWT was considered effective in reducing pain and improving functionality based on a recent systematic review and metanalysis. Nevertheless, further studies were requested by authors, as well as commentators to investigate ESWT's long-term effects and to determine optimal dosing intervals, intensity and frequency for treatment of knee OA [ 155].

In general, ESWT is considered a safe and non-invasive modality with minimal side effects. However, in a randomized controlled trial on people with low to moderate knee OA, low-dose ESWT for 4 weeks resulted in T2 changes indicative for cartilage degradation upon MRI. As T2 changes did not differ significantly between placebo and ESWT, the authors concluded that ESWT is still an effective and safe modality for pain reduction and functional improvement in this particular patient group [ 155].

In canine practice, focused ESWT has not been as well tolerated as radial ESWT and in the past required sedation in the majority of dogs. Meanwhile, novel trode technologies and gradual increase of shockwave intensity and frequency throughout focused ESWT sessions may allow clinicians to sidestep the need for sedation in dogs (personal experience of authors).

4.4. Electrotherapy

4.4.1. Electrotherapy in Canine Osteoarthritis

The field of electrotherapy is very multifaceted and includes various types of applications differing between direct and alternating current. The latter is further divided into low (0-1000 Hz, e.g., transcutaneous electrical nerve stimulation, neuromuscular electrical stimulation), middle (1-100 kHz, e.g., interferential current) and high frequency (>100 kHz, e.g., microwave) applications. Patients with OA may benefit from several electrotherapeutic effects. An analgesic effect has been induced via direct stimulation of peripheral nerves [ 156] but has also been mediated by release of endorphins [ 157]. Electrotherapy may counteract secondary OA-induced periarticular muscular alterations: enhancing muscular activation, normalizing muscle tone and increasing metabolism [ 157] and blood flow [ 108]. Frequently, human OA guidelines erroneously equate the term electrotherapy with the technique of neuromuscular electrical stimulation (NMES). This is an inadequate simplification. As study results on NMES efficacy for OA are conflicting, these guidelines may rate electrotherapy as "not appropriate" or may not mention it at all subsequent to this simplification [ 19, 22]. However, other electrotherapeutic interventions such as interferential current have been considered promising for OA pain relief [ 158], while evidence for therapeutic efficacy of microwave therapy for OA is scarce in human and veterinary medicine and currently no recommendation can be made. Therefore, the three most common electrotherapy techniques applied in veterinary medicine are discussed in the following section.

4.4.2. Interferential Current

Interferential current (IC) is characterized by the diagonal crossing of two medium frequency alternating current loops (about 4000 Hz) with a difference in frequency (1-100 Hz). At the intersection of the two circuits, continuous phase shifts occur due to the frequency difference and initiate a low- frequency current (0-250 Hz). This low- frequency therapy allows for deep tissue penetration and can be applied without skin irritation to joints [ 159].

The evidence in canine OA includes two studies: a randomized placebo controlled cross-over clinical trial investigated the effect of IC on ground reaction force in dogs with hip osteoarthritis (100 Hz, 250 µs pulse duration, phase duration of 125 µs) [ 36]. The IC-treated dogs showed a significant increase in peak vertical force, but the sample size was small (n = 9) and there was no control group. An observational study in five dogs with musculoskeletal pain reported a good outcome regarding pain and observed increased mobility [ 159]. The best analgesic effect was reported for an intensity of 6 mA and a frequency of 80-100 Hz. Furthermore, a series of mild local muscle contractions was seen during the treatment with local hyperaemia, and the dogs showed a state of comfort.

A recent systematic review indicated that IC is superior for pain management of osteoarthritic knees in people, when compared with five other electrotherapeutic modalities [ 158]. Other IC-induced positive therapeutic effects for OA include oedema reduction and reduction of muscle spasms [ 159].

4.4.3. Neuromuscular Electrical Stimulation

Muscle strengthening is an important physiotherapeutic goal, as OA is associated with muscle atrophy and weakness. Neuromuscular electrical stimulation (NMES) is an electrotherapeutic intervention that can be utilized as an alternative to exercise for muscle strengthening, when patients are too painful or weak or have comorbidities prohibiting exercise [ 160]. Neuromuscular electrical stimulation has been recommended as modality for osteoarthritic dogs, although there is currently only extrapolated evidence supporting NMES in this patient group [ 156]. In a canine experimental model with severed cranial cruciate ligament, dogs treated with NMES showed improved lameness scores, larger thigh circumference, less crepitation and fewer radiographic OA changes compared to the control group [ 33]. Similar positive effects have been observed in people treated with NMES for knee OA, showing increased thickness and fascicle length in the vastus lateralis muscle, improved joint extension and stiffness and improved comfort and function compared after NMES therapy [ 161]. In a randomized controlled trial on 41 people with knee OA, home-based NMES showed significant improvement in function and muscle mass compared to the conventional exercise group and similar improvements compared to home-based resistance training [ 162]. However, a systematic comparative review did not confirm a significant NMES-induced pain reduction for human knee OA [ 158]. In people with knee OA, adherence to NMES based therapy has not been superior or inferior to voluntary exercise programmes with patient education [ 163]. Currently, NMES frequencies of 25-50 Hz with 150 and 250 ms pulse duration are recommended for muscular strengthening in people, while dogs often tolerate lower frequencies (<10 Hz) better [ 156].

4.4.4. Transcutaneous Electrical Nerve Stimulation

Transcutaneous electrical nerve stimulation (TENS) is a low frequency electrotherapeutic modality with mono- or (mostly) biphasic square-wave pulses (alternating current). The main mode of action is activation of a complex neuronal network by activating descending inhibitory systems in the central nervous system to reduce pain. This modality can be applied both locally or at the corresponding spinal segment. Conventional TENS (=h-TENS, 50-150 Hz, 2-50 µs pulse duration, low intensity, effect via Gate-Control-mechanism) and the so-called acupuncture-like TENS (=l-TENS, 1-10 Hz, 100-400 µs pulse duration, high-intensity, effect via distribution of endogenous endorphins) are most frequently used [ 156]. Only a few studies investigate efficacy of TENS for OA therapy in veterinary medicine. In several murine studies, TENS produced an analgesic effect in experimentally induced OA [ 164, 165, 166, 167, 168]. In a pilot study on dogs, the effect of h-TENS (70 Hz) was investigated after extraarticular stabilization of cranial cruciate ligament deficient osteoarthritic stifle joints. In this study, ground reaction forces improved significantly in the affected limbs starting immediately after h-TENS application. Although this significant effect persisted until 210 min after application, it was highest immediately after application and was not observed anymore upon a four day recheck [ 169]. In a non-blinded prospective randomized clinical trial on 29 overweight dogs with various osteoarthritic joints enrolled in a standardized weight loss protocol, dogs undergoing a more intense PT program with biweekly TENS had a significantly more even peak vertical force symmetry between affected and non-affected limbs compared to dogs undergoing a regular outpatient PT program from day 60 until the end of the study [ 170]. However, there was no significant difference between pain scores and vertical impulse symmetry between groups. It remained unclear whether the positive effects observed were associated with TENS application or the more intense PT care with add-on supervision and in-house PT sessions. Empirically, TENS with high intensity and longer treatment duration (2-3 times per week, for 5-6 weeks, each session 30 min) is recommended for dogs with chronic conditions such as OA [ 59].

In human medicine, systematic reviews on efficacy of TENS for OA are contradictory. Whereas one review "could not confirm that transcutaneous electrostimulation is effective for pain relief in osteoarthritic knee joints" [ 171], other authors concluded that TENS is effective [ 172]. This discrepancy is probably associated with the current suboptimal study quality (small sample size, poor methodological quality, inadequate randomization and blinding) [ 168, 173]. Nevertheless, the National Institute for Health and Care Excellence in the UK currently recommends TENS for OA pain in humans (last update in 2020).

4.4.5. Capacitive-Resistive Electric Transfer (CRET)

The term capacitive-resistive electric transfer (CRET) refers to a non-invasive electro-thermal therapeutic modality, where electric currents are applied within the radiofrequency range of 400-450 kHz [ 174]. Capacitive-resistive electric transfer has been utilized in human patients with muscle, bone, ligament and tendon lesions with the goal to decrease pain [ 174, 175, 176, 177]. This modality utilizes a generator of long-wave currents and electrodes with multifrequency sequential systems of emission to transfer energy to tissues in capacitive and resistive modes [ 175]. Superficial tissues are targeted in capacitive mode, while deeper tissues such as tendons, bone and cartilage are affected in resistive mode. CRET has been shown to elicit thermal effects subsequent to the electrical resistance of tissues but will not cause overheating due to heat dissemination by circulating blood [ 174, 178, 179, 180]. Capacitive-resistive electric transfer improves blood circulation and subsequently allows for enhanced evacuation of inflammatory catabolites and tissue relaxation [ 180].

Osteoarthritic patients treated with CRET may benefit from this deep thermal effect (see therapeutic ultrasound), but also from a direct cellular effect associated with subthermal CRET currents. Subthermal CRET at 448 kHz promotes proliferation of human mesenchymal stem cells in injured tissues based on in vitro studies [ 174].

Literature on CRET application for OA is currently limited, but superior pain control and/or functional improvements were observed in two randomized prospective double-blinded studies on people with mild to moderate knee osteoarthritis [ 175, 181]. In one study, six CRET sessions of 20 min duration improved strength, function and pain control significantly directly after the six treatments and after 1 and 3 months compared to the sham treated control group [ 175].

Further studies are needed to confirm efficacy for different joints, more severe OA and different species. Optimal therapeutic CRET parameters for OA therapy still have to be determined.

Osteoarthritis is a global canine health problem. In human medicine, general practitioners are considered to be the main care providers for OA patients [ 182]. Thus, providing evidence-based guidelines for practitioners is imperative to improve quality of care of OA management [ 182]. This statement appears equally applicable to canine OA management. The authors intended to weigh the impact of different physiotherapeutic measures on dogs with OA utilizing the concept of the "Physiotherapy Pyramid". Similar concepts have been established for human OA therapy [ 27]. In human medicine, such guidelines ideally take cost effectiveness, short and long-term clinical effectiveness, as well as relative therapeutic efficacy and time requirements for therapeutic measures into consideration.

In veterinary medicine, evidence-based information on efficacy of physiotherapeutic measures is still scarce but constantly evolving. Subsequently, the current "Physiotherapy Pyramid" concept proposed in this review is based on common sense, evidence based veterinary information and information extrapolated from the human OA literature. However, the jury is definitely still out with regard to relative therapeutic efficacy of the different available therapeutic measures. Adaptations of the pyramid are needed depending on the evidence rising from future research.

Human OA is a disease with chronic non-curable character associated with very high healthcare cost. Considering this enormous economic burden, cost-effectiveness of physiotherapeutic measures in OA patients has become an important factor that is routinely evaluated in human medicine [ 183].

In veterinary medicine, the economic impact of OA has been calculated for an equine population [ 184] but has not been established for dogs yet [ 121], except for estimations by the veterinary health industry and insurances. Studies on the cost for physiotherapeutic measures spent for osteoarthritic dogs are missing, except for LLLT in a Midwestern state in the United States [ 121]. To the authors' knowledge, there is a complete lack of studies evaluating cost efficacy of PT measures for osteoarthritis in dogs.

Writing-original draft preparation, S.L., M.A.M. and J.M.; review and editing S.L., M.A.M. and J.M. All authors have read and agreed to the published version of the manuscript.

The APC was funded by Medical Education Corpus on behalf of Vetoquinol.

The authors thank the Vetoquinol Xpertise Scientific Committee for their insights and Medical Education Corpus, an independent medical publishing and communication agency, for editorial support.

S.L. and J.M. received travel fees and consulting fees from Vetoquinol as members of a Scientific Committee. M.A.M.'s current position is supported by Vetoquinol.

1. Lauer, S. Preword. In Essential Facts of Physical Medicine, Rehabilitation and Sports Medicine in Companion Animals; Bockstahler, B., Ed.; VBS GmbH: Babenhausen, Germany, 2019; pp. 3-4. [Google Scholar]

2. Marcellin-Little, D.J.; Levine, D.; Millis, D.L. Physical rehabilitation for geriatric and arthritic patients. In Canine Rehabilitation and Physical Therapy; Millis, D.L., Levine, D., Eds.; Elsevier: Amsterdam, The Netherlands, 2014; pp. 628-641. [Google Scholar]

3. McLean, H.; Millis, D. Treatment plans (osteoarthritis). In Essential Facts of Physical Medicine, Rehabilitation and Sports Medicine in Companion Animals; Bockstahler, B., Wittek, K., Levine, D., Maierl, J., Millis, D., Eds.; VBS GmbH: Babenhausen, Germany, 2019; pp. 581-585. [Google Scholar]

4. Langley-Hobbs, S. Patients with orthopedic disease. In BSAVA Manual of Canine and Feline Rehabilitation, Supportive and Palliative Care: Case Studies in Patient Management; Lindley, S., Watson, P., Eds.; British Small Animal Veterinary Association: Quedgeley, UK, 2010; pp. 224-231. [Google Scholar]

5. Fox, S.M. Multimodal Management of Canine Osteoarthritis, 2nd ed.; Group T and F, Ed.; CRC Press: Boca Raton, FL, USA, 2016. [Google Scholar]

6. Millis, D.L.; Drum, M.; Levine, D. Therapeutic exercises: Early limb use exercises. In Canine Rehabilitation and Physical Therapy; Millis, D.L., Levine, D., Eds.; Elsevier: Amsterdam, The Netherlands, 2014; pp. 495-505. [Google Scholar]

7. Millis, D.L.; Levine, D. Exercises for proprioception and balance. In Canine Rehabilitation and Physical Therapy, 2nd ed.; Millis, D.L., Levine, D., Eds.; Elsevier: Amsterdam, The Netherlands, 2014; pp. 484-493. [Google Scholar]

8. Zink, C.; Van Dyke, J. Canine Sports Medicine and Rehabilitation, 2nd ed.; Wiley Blackwell: Hoboken, NJ, USA, 2018. [Google Scholar]

9. Carrier, D.R.; Deban, S.M.; Fischbein, T. Locomotor function of forelimb protractor and retractor muscles of dogs:evidence of strut-like behavior at the shoulder. J. Exp. Biol. 2008, 211 Pt 1, 150-162. [Google Scholar] [CrossRef] [Green Version]

10. Henderson, A.; Levine, D.; Millis, D.; Drum, M. Protocol Development and Protocol. In Canine Rehabilitation and Physical Therapy, 2nd ed.; Millis, D.L., Levine, D., Eds.; Elsevier: Amsterdam, The Netherlands, 2014; p. 711. [Google Scholar]

11. Millis, D.L.; Levine, D. Range of motion and stretching exercises. In Canine Rehabilitation and Physical Therapy, 2nd ed.; Millis, D.L., Levine, D., Eds.; Elsevier: Amsterdam, The Netherlands, 2014; pp. 431-446. [Google Scholar]

12. Fitzpatrick, R.; McCloskey, D.I. Proprioceptive, visual and vestibular thresholds for the perception of sway during standing in humans. J. Physiol. 1994, 478 Pt 1, 173-186. [Google Scholar] [CrossRef]

13. Saussac, A.; Sawaya, S.G. Impact of a training program with the motorized platform Imoove-Vet in agility dogs. In Proceedings of the 6th VEPRA-1st ECVSMR Conference 2019, Ghent, Belgium, 19-21 September 2019; p. 140. [Google Scholar]

14. Millis, D.L.; Levine, D. Therapeutic exercise and manual therapy. In Canine Rehabilitation and Physical Therapy, 2nd ed.; Millis, D.L., Levine, D., Eds.; Saunders: Philadelphia, PA, USA, 2014; pp. 431-446. [Google Scholar]

15. Barnicoat, F.; Wills, A. Effect of water depth on limb kinematics of the domestic dog (Canis lupus familiaris) during underwater treadmill exercise. Comp. Exerc. Physiol. 2016, 12, 199-207. [Google Scholar] [CrossRef]

16. Ebelt-Paprotny, R.P.; Taxhet, G.; Wappelhorst, U. Leitfaden Physiotherapie; Elsevier Urban & Fischer: Munich, Germany, 2008. [Google Scholar]

17. Bellew, J.W. Therapeutic Modalities Past, Present, and Future: Their Role in the Patient Care Management Model. In Modalities for Therapeutic Intervention, 6th ed.; Bellew, J.W., Michlovitz, S.L., Nolan, T.P., Jr., Eds.; F. A. Davis Company: Philadelphia, PA, USA, 2016. [Google Scholar]

18. LoGiudice, R.J.; Starr, L. Rehabilitation for Geriatric Patients. In Canine Sports Medicine and Rehabilitation; John Wiley & Sons, Inc.: Hoboken, NJ, USA, 2018; pp. 454-478. [Google Scholar] [CrossRef]

19. Niebaum, K.; McCauley, L.; Medina, C. Rehabilitation Physical Modalities. In Canine Sports Medicine and Rehabilitation; John Wiley & Sons, Inc.: Hoboken, NJ, USA, 2018; pp. 136-176. [Google Scholar] [CrossRef]

20. Monici, M.; Millis, D.L.; Ciuperca, I.; McCarthy, D. Laser therapy. In Essential Facts of Physical Medicine, Rehabilitation and Sports Medicine in Companion Animals; Bockstahler, B., Ed.; VBS GmbH: Babenhausen, Germany, 2019. [Google Scholar]

21. Bockstahler, B.; Levine, D. Therapeutic ultrasound. In Essential Facts of Physical Medicine, Rehabilitation and Sports Medicine in Companion Animals; Bockstahler, B., Wittek, K., Levine, D., Maierl, J., Millis, D.L., Eds.; VBS GmbH: Babenhausen, Germany, 2019. [Google Scholar]

22. Levine, D.; Bockstahler, B. Electrical stimulation. In Canine Rehabiliation and Physical Therapy; Millis, D.L., Levine, D., Eds.; Elsevier: Amsterdam, The Netherlands, 2014; pp. 342-358. [Google Scholar]

23. Bockstahler, B.; Levine, D.; Ciuperca, I. Electrotherapy. In Essential Facts of Physical Medicine, Rehabilitation and Sports Medicine in Companion Animals; Bockstahler, B., Wittek, K., Levine, D., Maierl, J., Millis, D.L., Eds.; VBS GmbH: Babenhausen, Germany, 2019. [Google Scholar]

24. Levine, D. The effect of TENS on osteoarthritic pain in the stifle of dogs. In Proceedings of the 2nd International Symposium on Rehabilitation and Physical Therapy in Veterinary Medicine, Knoxville, Tennessee, 10-14 August 2002. [Google Scholar]

25. Oke, S.L.; McIlwraith, C.W.; Moyer, W. Review of the economic impact of osteoarthritis and oral joint-health supplements in horses. In Proceedings of the 56th Annual Convention of the American Association of Equine Practitioners, Baltimore, MD, USA, 4-8 December 2010. [Google Scholar]

Disclaimer/Publisher's Note: The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content.

# data[].attributes.attachment_link.title
Physiotherapeutic Strategies and Their Current Evidence for Canine Osteoarthritis

# data[].attributes.attachment_link.description
Osteoarthritis (OA) is a common and debilitating condition in domestic dogs. Alongside pharmaceutical interventions and weight loss, exercise and physiotherapy (PT) are important measures in maintaining patient mobility and quality of life. Physiotherapy for OA aims to reduce pain, optimize muscular function and maintain joint function.

# data[].attributes.body
https://scholar.google.com/scholar_lookup?hl=en&volume=12&publication_year=1997&pages=34-44&journal=Semin.+Vet.+Med.+Surg.&author=V.+Biourge&title=Nutrition+and+liver+disease

# data[].attributes.body
Fluid Overload in Small Animal Patients - ScienceDirect

# data[].attributes.body
The nurses' role in managing gut stasis in rabbits | The Veterinary Nurse (magonlinelibrary.com)

Johanson, K., 2014. The nurses' role in managing gut stasis in rabbits. The Veterinary Nurse. Available at The nurses' role in managing gut stasis in rabbits | The Veterinary Nurse (magonlinelibrary.com) Accessed on: 16.02.2024

# data[].attributes.body
o   https://www.vettimes.co.uk/app/uploads/wp-post-to-pdf-enhanced-cache/1/nursing-the-spinal-patient.pdf

# data[].attributes.headline
Hydrotherapy for the osteoarthritic dog: why might it help and is there any evidence?

# data[].attributes.subject
Hydrotherapy for the osteoarthritic dog: why might it help and is there any evidence?

# data[].attributes.headline
Effects of IV Fluids in Dogs and Cats With Kidney Failure

# data[].attributes.subject
Effects of IV Fluids in Dogs and Cats With Kidney Failure

# data[].attributes.attachment_link.readable_text
The Ohio State University College of Veterinary Medicine, Columbus, OH, United States

Intravenous fluid therapy has long been the mainstay of treatment of kidney disease, including acute kidney injury and uremic crisis associated with chronic kidney disease. Careful management of fluid dose is critical, as animals with kidney disease may have marked derangements in their ability to regulate fluid homeostasis and acid-base status. Understanding of the physiology of renal fluid handling is necessary, along with repeated attention to parameters of fluid status, electrolytes, and acid-base balance, to achieve optimal hydration status and avoid further damage or decrease in function from dehydration or overhydration.

Introduction

Fluid therapy is the most commonly administered intravenous treatment for hospitalized veterinary patients. Adequate fluid resuscitation is essential for the restoration of cardiac output, systemic blood pressure, and renal perfusion. Achieving an appropriate level of volume management requires knowledge of underlying pathophysiology, evaluation of volume status, selection of appropriate solution for volume repletion and maintenance, and modulation of the tissue perfusion ( 1).

Recently, Hoste et al. ( 2) proposed four distinct phases (ROSE) of intravenous fluid therapy for humans with critical illness: (R) resuscitation, (O) optimization, (S) stabilization, (E) evacuation. In overview, the resuscitation phase anticipates an escalation of fluid therapy in patients with life-threatening shock (low blood pressure, signs of impaired perfusion, or both) and is characterized by the use of fluid bolus therapy (rapid infusion to correct hypotensive shock; ~10 ml/kg balanced isotonic crystalloid over 15 min; typically not exceeding a total of three boluses). When transitioning to the optimization phase, the patient should no longer be in immediate life-threatening danger, but in a stage of compensatory shock and high risk for decompensation. At this point, additional fluid therapy is given more cautiously with the intent of optimizing cardiac function and improving tissue perfusion. The goal is to administer the volume necessary to alleviate organ dysfunction. Fluid challenges, defined as a small volume over short period of time (~5 ml/kg over 20 min), are typically given in this phase to test the effects of delivering more volume ( 3). Some patients may bypass the resuscitation phase (with no evidence of hypotension) and present to the hospital in a compensated state. In these first two phases, compensatory neuroendocrine reflexes and possible renal dysfunction result in sodium and water retention, contributing to a positive fluid balance. Progression to the stabilization phase encompasses a point at which the patient is at steady state without signs of shock. Fluid therapy in this phase is used for ongoing maintenance losses (renal, gastrointestinal, insensible); as well as rehydration if the patient is experiencing ongoing losses due to unresolved pathology. Patients may experience temporary deterioration and revert back to the optimization phase if faced with a newly developed infection or organ dysfunction. Lastly, the evacuation phase is characterized by the removal of fluids and promotes a negative fluid balance ( 2, 4). This may need to be achieved with low doses of loop-diuretics (authors suggest 0.25-0.5 mg/kg IV). The physiological response to fluids and underlying conditions are dynamic over time, thus fluid administration should be based on repeated assessment of cumulative fluid balance and hemodynamic status. Generally, hemodynamic status can be assessed using dynamic testing to evaluate fluid responsiveness ( 5).

Interest in intravenous fluid therapy and its side effects has increased in recent years. Many trials have investigated the colloid/crystalloid debate, while others have provided guidance on selecting the optimal crystalloid solution ( 6). In addition, the role of chloride and its detrimental effect on kidney function has garnered much attention ( 7- 10). Much of the research has focused on fluid therapy in the resuscitation phase, in which people receive large amounts of fluid over a short period of time. In reality, hospitalized people receive fluids and electrolytes for other reasons including maintenance therapy, medications, and replacement for existing or ongoing losses. The cumulative fluid delivery frequently exceeds fluid loss, leading to a net positive fluid balance or "fluid creep." With this principle in place, additional considerations need to be made for renal patients with altered sodium handling.

Pathophysiology

The primary function of the kidney is to maintain a stable extracellular compartment by selective retention/elimination of water, electrolytes, and other solutes. This is achieved via filtration of the circulating blood into ultrafiltrate from the plasma, selective reabsorption from tubular fluid into peritubular capillary blood, and selective secretion from peritubular capillary blood into the tubular fluid. Glomerular filtration ( net ultrafiltration pressure) is determined by the difference in hydrostatic and oncotic pressure gradients between the glomerular plasma and the filtrate in Bowman space. Each nephron has its own single-nephron glomerular filtration rate (SNGFR), and the sum of the SNGFRs of the functioning nephrons make up the total glomerular filtration rate (GFR). Maintaining a normal GFR is dependent on adequate renal perfusion.

Acute kidney injury (AKI) is defined as a rapid decline in GFR through the measurement of serum creatinine and urine output. There are inherent challenges with this definition as creatinine is poorly correlated with GFR at low levels of renal dysfunction ( 11). Clinically, AKI is grouped into three etiologies: pre-renal, renal, and post-renal. Pre-renal azotemia is characterized by a decrease in GFR due to a decrease in renal perfusion pressure without damage to the renal parenchyma ( 12). Post-renal causes of AKI are characterized by acute obstruction of urinary flow, leading to increases in intratubular pressure, impaired renal blood flow and inflammatory processes, and decreased GFR ( 13). Renal azotemia is associated with a sudden onset of renal parenchymal injury, characterized by the kidneys inability to meet excretory, metabolic, and endocrine demands of the body. AKI represents a continuum of renal injury from mild, clinically inapparent nephron loss to severe acute renal failure requiring renal replacement therapy. The International Renal Interest Society (IRIS) AKI Grading scheme has been developed in veterinary medicine to determine appropriate grading in animals with AKI ( 14).

Intrinsic renal etiologies can be challenging to evaluate due to a wide variety of injuries that can occur to the kidney. In general, renal damage can be divided into four major structural groupings: the tubules, glomeruli, interstitium, and intra-renal blood vessels. Tubular damage can arise from either ischemic injury (decreased renal perfusion) or nephrotoxic compounds (exogenous and endogenous). Severe acute glomerulonephritis secondary to immune-complex disease causes glomerular damage. Interstitial damage can result from acute interstitial nephritis secondary to medications or infectious etiologies (leptospirosis, pyelonephritis, etc.). Lastly, vascular damage can occur secondary to injury to intra-renal vessels (thrombosis, hypertension, etc.), subsequently decreasing renal perfusion and diminishing GFR ( 15). Ischemia and nephrotoxic agents (e.g., certain drugs, plants, ethylene glycol, etc.) account for the majority of renal injury in human medicine as well as veterinary medicine ( 16).

Renal tubular injury is associated with a decrease in GFR and is divided into different phases of AKI, which are directly related to the cellular events that occur during the injury and recovery process. The initiation phase occurs when renal blood flow decreases, resulting in cellular ATP depletion and subsequent tubular epithelial cell injury. These changes alter the ability of tubular epithelial cells and vascular endothelial cells to maintain normal renal function (reabsorption and secretion), as well as up-regulate a variety of chemokines and cytokines to initiate an inflammatory cascade ( 17). The extension phase is characterized by continued hypoxia following the initial ischemic event and an inflammatory response, most prominent in the outer medullary region of the kidney. During this phase, vascular endothelial damage likely plays a key role in the continued ischemia of the tubular epithelium, as well as the inflammatory response. Cells in the outer medullary region undergo injury and death via necrosis and apoptosis ( 18). The cellular injury in this region leads to the continual reduction in GFR, whereas cells of the proximal tubule in the outer cortex, where blood flow has returned, undergo cellular repair and improve morphologically ( 19). The maintenance phase consists of cells undergoing repair, migration, apoptosis, and proliferation to reestablish and maintain cellular and tubular integrity. The GFR usually remains stable at the level determined by the severity of the initial event. Cellular repair and reorganization results in slowly improving cellular function, setting the stage for improvement in organ function. Blood flow returns toward normal and epithelial cells establish intracellular and intercellular homeostasis ( 19). During the recovery phase, cellular differentiation continues, epithelial polarity is re-established, and normal cellular and organ function returns ( 20). Alternatively, renal repair can be maladaptive with inflammation, fibrosis, and vascular rarefaction leading to persistent cell and tissue malfunction and eventually chronic kidney disease ( 21). AKI and chronic kidney disease (CKD) are increasingly recognized as related entities representing a continuum of disease ( 22).

The assessment of renal recovery is controversial with a lack of clear, defined parameters. Despite the limitations, the most obvious definition of full recovery from AKI is the absence of AKI criteria. Partial recovery is defined as a fall in AKI grade. Recovery may occur early, after the insult (within 7 days), or later, during the proposed period of acute kidney disease (AKD), which is defined as AKI persisting for 7-90 days ( 23). Lack of complete recovery in the first 90 days is defined as CKD.

Disruption of normal renal function impairs maintenance of homeostasis. A normochloremic high anion gap metabolic acidosis is common, due to inadequate excretion of organic and inorganic acids such as phosphate and sulfate. Hyperkalemia is also common when urine production is low and distal tubular secretion of potassium is impaired. Conversely, hypokalemia may develop with polyuria, as the high urine flow through the distal tubule enhances potassium secretion by maintaining a concentration gradient between the tubular cells and the ultrafiltrate in the tubule lumen. Disorders of sodium are variable and depend on the degree of impairment of sodium reabsorption relative to water excretion. Because of impaired filtration and thus excretion of phosphate, leading to hyperphosphatemia, an ionized hypocalemia may develop acutely.

Aims of Fluid Resuscitation

The physiological rationale for fluid administration in AKI and CKD is to optimize intravascular circulating volume, increase cardiac output and perfusion pressure, with the aim of improving renal blood flow, renal oxygen supply, and GFR ( Table 1). Hypotension is a strong risk factor for AKI, yet preserving systemic arterial pressure alone is not adequate for renal perfusion. Renal tissue perfusion relies on the pressure in the post-glomerular arterioles, which is often much lower than the systemic MAP ( 21). Conversely, fluid resuscitation beyond correction of hypovolemia does not increase the chances of renal recovery. Excessive fluid administration has been associated with the development of AKI, secondary to intrarenal compartment syndrome and venous congestion, attributed to the kidneys being encapsulated organs ( 24, 25). It is imperative to understand the physiological response to fluids and underlying condition related to AKI are dynamic, thus fluid administration should be based on repeated assessments of the patient and relevant biomarkers. Overall fluid and hemodynamic status, using dynamic tests of fluid responsiveness are utilized to determine the need for additional fluid therapy ( 5). The clinician is forced to walk a tight rope between too few fluids, which can lead to further progression of AKI from ongoing renal ischemia, and too much fluids leading to systemic complications and organ dysfunction.

Table 1. Goals of fluid resuscitation in AKI.

Fluid Types

Fluids are differentiated into crystalloids and colloids. Disregarding the impact of fluid overload, there is growing evidence that renal function is affected by the type of fluid and certain fluids are associated with an increased risk of AKI ( 24, 26, 27).

Isotonic Crystalloids

Isotonic crystalloids are the accepted first-line IV fluid in most ICU patients. There is ongoing research as to which isotonic crystalloid, 0.9% NaCl vs. a buffered crystalloid (LRS, Plasma-Lyte, Hartmann's), is appropriate in people at risk for AKI. The impact of chloride concentration on renal function has been researched in a Greyhound model, showing that increasing plasma chloride levels produce progressive renal vasoconstriction and decreased GFR. These effects appeared to be related to tubular chloride reabsorption ( 28). Both animal research and studies in healthy human volunteers suggest that hyperchloremia may lead to renal vasoconstriction, reduction in renal cortical tissue perfusion and glomerular filtration, along with longer periods of fluid retention compared with buffered crystalloids ( 29).

Clinical trials comparing various crystalloid fluids in critically ill people at risk of AKI have produced conflicting results ( 7, 9, 10, 30). The SMART and SALT-ED trials are the largest randomized controlled trials comparing 0.9% NaCl and buffered crystalloids. Both found a significant reduction in the risk of major kidney events within 30 days, in the group treated with buffered solutions ( 9, 10). Despite these findings, the optimal fluid in people at risk of AKI has not been identified. It is of the authors opinion that balanced crystalloids should be used for resuscitation and replacement therapy. Dextrose-containing solutions should not be used as a replacement solution unless the patient is hypoglycemic or a neonate/infant.

Hypotonic Crystalloids

Maintenance solutions (hypotonic crystalloids) are administered to meet the patient's basal requirements of water and electrolytes. Specific maintenance solutions are commercially available but are far from ideal. Studies in people have shown over the course of an ICU admission, a substantial amount of daily fluid volume is delivered with maintenance/replacement fluids, medications, and nutrition compared to resuscitation fluids ( 31). Generally, the overall sodium and chloride load administered with maintenance and replacement fluids is not taken into consideration, even though these fluids account for a large portion of the daily fluid volume in these patients. There is debate whether isotonic or hypotonic solutions should be used for maintenance fluid therapy. Much of the data in children has showed a possible risk of hyponatremia ( 32, 33). Studies in human adults indicate a more positive fluid balance and decreased urine output with isotonic solutions compared to hypotonic solutions ( 34, 35). These studies bring to light the concept of "fluid creep" secondary to high daily sodium administration with isotonic crystalloids leading to fluid retention. Further studies in patients with AKI are needed to make a recommendation, but in theory these patients with altered sodium handling and higher chloride concentrations reaching the macula densa would benefit from a hypotonic solution in the stabilization phase. At this stage, the authors preferentially use hypotonic solutions to reduce sodium load in animals with renal dysfunction. Monitoring the animal's electrolytes and acid-base status frequently is essential for prescribing the appropriate fluid during the resuscitation and early stabilization phase.

Synthetic Colloids

In human medicine, the administration of synthetic colloids has been linked with the development of acute kidney injury (AKI) and the need for renal replacement therapy (RRT) in ICU patients, especially those with sepsis ( 27, 36). Findings from meta-analyses suggest this may depend on patient cohort, but did confirm a higher risk of AKI and conflicting reports on mortality ( 37). In veterinary medicine, there is inconclusive evidence on the development of AKI in dogs and cats treated with hydroxyethyl starches (HES). The majority of the studies are retrospective, with inconsistent definitions of AKI ( 38- 41). Extrapolating from human medicine, in most clinical situations, the risks outweigh the benefits and alternative volume replacement therapies should be used in place of HES.

Natural Colloids

Albumin is a natural colloid, specifically studied in resuscitation, that has not been shown to have consistent survival benefit. Although, albumin is considered safe in people at risk or with established AKI, studies are needed to assess potential benefits ( 24, 26, 42). The most recent Surviving Sepsis Campaign recommendations state that albumin in addition to crystalloids may be considered in limited quantities for early resuscitation and subsequent intravascular volume replacement in people with sepsis or septic shock ( 43). HES should be avoided in this patient population, thus other colloids (FFP and albumin) may be considered in limited quantities. There are no studies in veterinary medicine regarding the use of FFP or albumin in dogs or cats with renal dysfunction.

Fluid Dose

There are few evidence-based studies evaluating the dose response of intravenous fluids in animals with kidney dysfunction. Standard formulas for what is commonly called a maintenance intravenous fluid rate make two presumptions, namely that animals have similar evaporative losses and that urine output is "average" (1-2 mL/kg/h). In patients with renal dysfunction, standard maintenance formulas do not apply and fluid requirements must be assessed on an individual basis. Evaporative losses in dogs and cats are predominantly through the respiratory tract, as perspiration is generally negligible, and salivary and fecal losses are generally not accounted for when determining fluid balance. Respiratory losses can be quite dissimilar and are impacted by environmental temperature and humidity, and by patient activity level. In one study of healthy dogs, evaporative losses varied from 8.1 to 75.7 ml/kg/day, with a mean of 27 mL/kg/day ( 44- 46). Barking and panting increased evaporative loss compared to losses in quiet dogs. In cats, insensible loss ranged from 12.4 to 29 ml/kg/day in different studies ( 44, 47, 48). Insensible loss is generally considered to be 22 ml/kg/day, regardless of demeanor. In the animal with kidney disease, urine volume is highly variable, ranging from extreme polyuria to anuria, necessitating adjustment of fluid administration rates based on the specific, and changing individual animal fluid requirements. Accurate urine output quantification is obtained through the placement of a urinary catheter. Alternatively, if urine cannot be accurately measured due to the inability to place a urinary catheter, a towel or diaper with a pre-specified weight can be placed in the cage. The difference in the weight of the towel or diaper when the animal urinates is approximately equal to the urine produced (1 g increase in weight = 1 mL urine).

Westgren et al. evaluated 11 dogs with suspected kidney disease using scintigraphy to measure GFR before and after a 15 ml/kg intravenous bolus of crystalloid fluid ( 49). The GFR appeared to increase 31% after the fluid bolus when measurements were calculated based on weight. However, when GFR was evaluated based on plasma volume, there was no change in GFR after fluid therapy. Given the effects that a fluid bolus can have on renal dynamics, this new method of calculating GFR suggests that fluid therapy does not acutely increase GFR, although the technique needs further validation.

In one study of systemically healthy dogs undergoing an orthopedic surgery and receiving standard intraoperative fluid rates (10 ml/kg/h of lactated Ringers solution), the median urine output was 0.46 mL/kg/h ( 50). GFR was stable during anesthesia. These dogs gained a median of 1.1 L of fluid (3.4% of pre-anesthesia body weight) over the 4-h anesthetic period, which was mostly distributed to the extracellular space, despite having normal kidney function. The neurohumoral effects of anesthesia appear to be able to affect renal hemodynamics even in normal animals and the effects of depth of anesthesia on urine output requires further investigation.

Brandstrup et al. compared goal directed therapy to a zero-balance approach in humans undergoing colorectal surgery ( 51). In the goal directed approach, fluid was administered to maintain near maximal stroke volume, whereas the zero-balance approach only replaced fluid losses. There was no difference in outcomes. Thus, a zero-balance approach appears safe and requires less invasive monitoring. Similar studies in clinical veterinary patients with kidney disease do not exist, although this approach merits investigation. Zero-balance fluid administration can be achieved by monitoring urine output and adjusting fluid dose accordingly ( Table 2).

Table 2. Fluid dose guidelines.

Complications

Fluid overload is a commonly mentioned negative side effect of intravenous fluid therapy, especially in patients with initial renal dysfunction. It is well-documented in humans, and sparse evidence in veterinary medicine indicates that fluid overload contributes to progression of kidney dysfunction and increase in mortality ( 52- 58). In addition, fluid overload has severe consequences affecting many different organs including the central nervous system, cardiovascular, pulmonary, hepatic, renal, and gastrointestinal tract ( Figure 1) ( 4, 59). Excessive fluid administration is an iatrogenic complication that results in renal congestion, subsequently worsening renal perfusion and GFR due to interstitial edema. This is an area of harm seen in human and veterinary patients in attempts to "diuresis" the kidneys, ultimately leading to progressive renal dysfunction. Monitoring urine output in conscious animals is a sensitive and early marker for the detection of AKI, but also enhances the clinician's ability to track fluid overload and assess response to therapy. Cumulative fluid balance is the sum total of fluid accumulation over a set period of time and the percentage of fluid accumulation is defined by dividing the cumulative fluid balance by the patient's baseline body weight and multiplying by 100%. Diuretics remain a valid therapy for relieving symptoms and improving pathophysiological states of fluid overload, even in people with renal dysfunction ( 60- 62). A urine output of 3-4 ml/kg/h after diuretic use has been shown to rarely cause intravascular volume depletion as intravascular refilling can equilibrate at that rate ( 25). With the limitations in detecting early signs of AKI due to the lack of active renal biomarkers in veterinary medicine, the authors recommend placing a urinary catheter in unstable cardiovascular, azotemic people to accurately monitor urine production. Because serum creatinine and oliguria are often late signs of significant AKI, a functional assessment of renal tubular function can indicate risk of AKI progression. Furosemide is a loop diuretic with ideal pharmacokinetic properties to assess tubular function. It is not effectively filtered by the glomerulus but is bound to serum proteins and gains access to the tubular lumen via active secretion in the proximal tubule. Once in the tubular lumen, furosemide inhibits active chloride transport throughout the ascending thick limb of Henle, preventing sodium reabsorption and inducing naturesis to increase urine flow ( 63). A furosemide stress test (1-1.5 mg/kg IV bolus) can be administered to oliguric patients that are assessed to be euvolemic or fluid overloaded to accurately determine AKI progression and need for renal replacement therapy ( 64). In human medicine, a 2-h urine cutoff of <200 mL produced the best sensitivity (87.1%) and specificity (84.1%) and was a predictor in progression of AKI ( 63). Unfortunately, this has not been studied in veterinary medicine, but extrapolating from humans, a response of 1.5 ml/kg/h roughly equates to the 200 mL over the 2 h time interval. Repeated administration of furosemide in a non-responsive patient can lead to adverse effects such as ototoxicity, which has been reported in humans.

Figure 1. Fluid overload adversely impacts many body systems. Adapted from Prowle et al. ( 25).

The use of diuretics to increase urine output does not improve renal function. If renal replacement therapy is not available, diuretics may help control hyperkalemia by increasing distal tubular flow and allow more liberal administration of nutrition and medications with less risk of volume overload. Despite the widespread use of diuretics in human medicine, there are few guidelines pertaining to the dose and interval of administering furosemide. A recent meta-analysis in humans showed continuous furosemide was associated with greater diuretic effect in total urine output as compared to bolus dosing, although neither had any difference in mortality ( 65). The authors recommend the following doses (1-2 mg/kg IV q 6-8 h or 0.25-0.5 mg/kg/h IV) when administering furosemide. Hyperkalemia can be treated temporarily by causing an intracellular shift using regular insulin (0.5 u/kg IV with 1 g/kg IV dextrose). Beta-adrenergic agonists (e.g., terbutaline, albuterol) can be used as adjunctive therapy to shift potassium intracellularly but may require higher doses than need for bronchodilation. Bicarbonate therapy should be considered in dogs and cats with AKI and severe metabolic acidosis (i.e., pH <7.1 or serum bicarbonate <12 mEq/L). A significant beneficial effect has been shown in humans with AKI and severe metabolic acidosis to decrease the need for renal replacement therapy and overall mortality ( 66, 67).

Clinical Context

Management of dogs and cats with AKI involves treating the underlying cause and providing time for the kidneys to repair themselves. Appropriate fluid therapy is paramount in the medical management of AKI, aiming to restore hydration and euvolemia. The preconceived notion to increase the fluid rate and force diuresis in animals with AKI must be absolutely avoided. This is especially true in animals with established oliguria or a relative oliguria, in which they are unable to appropriately respond by increasing urine production, thus developing generalized edema that directly exacerbates further organ dysfunction. If the animal is not able to remove the excess fluid due to lack of kidney function, renal replacement therapy is indicated to help facilitate fluid removal and achieve appropriate fluid balance. It is only once the animal has established a consistent urine output and advanced to the polyuric phase, that it becomes reasonable to increase the fluid rate to match urine output. Emphasis is placed on the importance of frequent patient assessments (cumulative fluid balance) to determine the fluid needs of these patients.

Fluids should be gradually tapered when hydration and urine production are restored, fluid "in" and urine "out" are matched, and the serum creatinine has plateaued (i.e., no further improvement at this stage). The authors recommend decreasing the fluid rate by 15-20% every 8 h, with the goal of discontinuing intravenous fluids in a 48 h period. It is not uncommon for animals with AKI to require a feeding tube (esophagostomy or gastrostomy) to not only administer proper nutrition and meet the demands of the hypercatabolic state, but also supplement enteral fluids in a markedly polyuric animal. The feeding tube allows the owner to play an integral role in the recovery phase of AKI as well as reduce the time and cost associated with hospitalization. A less physiologic option for maintaining hydration in an animal with AKI is the use of subcutaneous fluids. Subcutaneous fluids involve administration of large quantities of "salt water" (LRS, 0.9% NaCl), making this option less than ideal for animals with intrinsic renal dysfunction.

Consideration for fluid type (hypotonic and balanced isotonic) along with reduction in cumulative sodium load is more physiologic for dysfunctional kidneys. Additional studies are needed to characterize the urine chemistry of dogs and cats that present with AKI ( 68). We have become more cognizant to the negative effects of intravenous fluids and will continue to make new discoveries how the kidneys function in a dysfunctional state. As we gather more data in animals with renal injury, the question becomes truly which fluid type is recommended for these animals?

Unfortunately, accurate assessment of animal weight, which is used as a surrogate for fluid status, is challenging, as the body converts to a hypercatabolic state in established AKI and loss of muscle mass. Luckily, providing nutrition and water through an established feeding tube (E-tube, PEG, G-tube) is an ideal way to help manage the catabolism of muscle and daily fluid requirement. Ultimately, the best fluid therapy is one that maintains euvolemia, with the goal of delivering fluid in the most physiologic manner (via the GI tract).

Author Contributions

CL and DG contributed to write the manuscript. All authors contributed to the article and approved the submitted version.

Conflict of Interest

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

The reviewer DC declared a shared affiliation with the authors to the handling editor at time of review.

References

45. Smith RC, Haschem T, Hamlin RL. Water and electrolyte intake and output and quantity of feces in the healthy dog. Vet Med Small Anim Clin. (1964) 59:743-8.
Google Scholar
47. Hamlin R, Tashjian R. Water and electrolyte intake and output and quantity of feces in healthy cats. Vet Med Small Anim Clin. (1964) 59:746-7.
Google Scholar

# data[].attributes.attachment_link.title
Effects of IV Fluids in Dogs and Cats With Kidney Failure

# data[].attributes.attachment_link.description
Intravenous fluid therapy has long been the mainstay of treatment of kidney disease, including acute kidney injury and uremic crisis associated with chronic kidney disease. Careful management of fluid dose is critical, as animals with kidney disease may have marked derangements in their ability to regulate fluid homeostasis and acid-base status.

# data[].attributes.headline
Clinical Value Blood Glucose Rabbit Gut stasis

# data[].attributes.subject
Clinical Value Blood Glucose Rabbit Gut stasis

# data[].attributes.body
https://bvajournals.onlinelibrary.wiley.com/doi/abs/10.1136/vr.100321

# data[].attributes.attachment_link.readable_text
Assuring optimal hydration is the single most important aspect in the treatment of kidney disease. The kidneys are made up of millions of small filtration units called "nephrons." Nephrons receive all the materials circulating in the bloodstream and must separate out the good stuff to keep (proteins, sugars, electrolytes etc.) from waste to be dumped (toxins, excess material etc.). The good stuff stays in the bloodstream while the waste is dissolved in water and made into urine. Because water is "good stuff" in and of itself, the kidney is designed to get rid of the waste material in the smallest amount of water possible.

Urine is made constantly and continuously by the kidneys. The ureters connect the kidney to the urinary bladder so that urine can be transported there and the bladder stores the urine until it is convenient to dump it into the environment. The system is very efficient and precise but it is driven by water. If the body becomes dehydrated, the kidney can't do its job.

Over a lifetime, nephrons are damaged and are no longer able to participate in the filtration process. They die from poor circulation, they become clogged by toxin sludge, or they may simply wear out. This is normal and is part of the wear and tear of living. Fortunately, we have many extra nephrons so losing some is not a big problem; that is, not a big problem until we have lost about two-thirds of them. At this point the remaining nephrons will have trouble keeping up with the waste removal demands of the body. Extra water is needed to remove the same amount of metabolic toxin so the patient begins to drink more. There may come a point where drinking water will not keep up with the toxin load and the patient will feel sick. Feeling sick means less activity and less water consumption which makes it even harder to get rid of the toxin load and a vicious cycle has been created.

This means that if the kidney disease is not detected until the patient is already feeling sick, less than one-third of the original number of nephrons are left. We need to maximize the efficiency of these remaining nephrons, and hopefully slow down their loss. We also need to get rid of enough toxin for the patient to feel good again.
The build-up of toxins is called "azotemia." Actually feeling sick from the toxins is called "uremia." Your pet can have azotemia without uremia but if they have uremia, they certainly also have azotemia.
Diuresis is the medical term for increased urine production. The patient may have already been doing this somewhat by drinking excessively but there comes a point when it is not possible to drink enough and toxins build up as mentioned. When the patient first begins to feel sick, he tends to eat less and drink less. Dehydration results, which is disastrous for the patient that already had an increased need for fluids to start with. To solve these problems, we will need to correct the dehydration and maximize the circulation through the remaining nephrons. This is accomplished by giving the patient more fluid, either intravenously in the hospital or under the skin in either the hospital or the home setting.

Intravenous (IV) Fluid Therapy

Intravenous fluid therapy involves placing an intravenous catheter in the leg or neck so that a continuous drip of fluids can be given directly into the bloodstream. The procedure is not painful nor stressful as after the catheter is placed, the patient simply relaxes in a hospital cage. After two or three days, lab tests are repeated to see what parameters have changed. Therapy is revised at that point to either continue IV fluids or discharge the patient with a new plan for home treatment.

IV fluid therapy offers many benefits to the kidney patient:

Continuous hydration means continuous maximized nephron activity and the most efficient toxin removal.

Rapid response to treatment (days).

Because hospitalization is needed for this treatment, a professional staff will be monitoring the patient's progress and can make rapid adjustments in adjunct therapy.

The disadvantages of IV fluid therapy include:

Expense of hospitalization.

Occasionally a patient dislikes the bandaging associated with the catheter and chews the catheter out. This incurs additional expense as the catheter is replaced and potentially the patient may need to wear an Elizabethan collar, which could be uncomfortable.

Stress from separation of pet and owner, though we find in most cases that it is the owner's stress and not the pet's that dominates. Most animals are comfortable in their cages, nothing that generates fear is happening, and they quickly habituate to the cage environment and activity viewed through the bars.

Subcutaneous Fluid Therapy

The word subcutaneous means under the skin. Here, fluids are given all at once in a pocket under the skin and the patient absorbs them gradually. Initially, intravenous fluid therapy is generally considered superior to subcutaneous fluid therapy but this depends on the blood test results of the patient; some are able to skip straight to subcutaneous fluids or are forced to by the expense of intravenous therapy. Fluids are typically given every couple of days with the frequency increasing if the pet gets worse or decreasing as the pet gets better.
Advantages of subcutaneous fluids include:

The procedure is easy for a client to learn and perform at home. Separation from the pet is not needed.

Because hospitalization is not needed, this form of therapy is much less expensive.

The procedure can be performed in the hospital on an outpatient basis if the patient is not cooperative at home.

Therapy is performed usually only every couple of days (though in more advanced cases could be once or even twice a day).

Disadvantages of subcutaneous fluids include:

The owner must be comfortable with sticking a needle into the pet's skin. This psychological hurdle is generally overcome after the owner performs the procedure a couple of times. There are also implantable injection ports available.

Changes in toxin level tend to occur more slowly (weeks). This makes subcutaneous fluids less appropriate for more advanced cases.

Large dogs often require inconveniently large volumes of fluids.

Some patients attempt to hide from the owner when they think the needle is coming and some people feel this changes the relationship with their pet in a negative way that may not justify the health benefits. It is important to realize that this is not the usual experience with subcutaneous fluids; most people find that the comfortable life quality for the rest of the day or next several days more than compensates for the 10 minutes of unpleasant fluid administration. Most pets are cooperative for fluid administration.

See more details on how to give subcutaneous fluids.

An alternative form of fluid administration utilizes the patient's own GI tract via an esophagostomy tube. The tube allows for relatively large amounts of water to be given without needles or hospitalization. In patients where heart disease is concurrent with kidney disease, there is a delicate balance that must be met between making the kidneys happy with extra circulating fluid yet not creating a fluid overload on the compromised heart. The GI tract creates a buffer in this situation; extra fluids will simply not be absorbed into the body. The esophagostomy method may lead to a loose stool but is much safer for a weak heart. Using the esophagostomy tube to give fluids also prevents you from struggling with a syringe into the pet's mouth. Such struggling is unpleasant for all parties involved and can lead to fluid aspiration into the lung. Use of the esophagostomy tube is generally struggle-free and by-passes the respiratory tract.

The esophagostomy tube is placed through a small hole in the esophagus (the passage connecting the mouth and stomach). Fluids can be administered through this tube and into the stomach thus avoiding the needle stick. The tube can stay comfortably in place for months but the hole will require regular cleaning and bandaging at home. A pet with an Esophagostomy tube should not be allowed outside unattended in case the tube or wraps become entangled in bushes, fences etc. General anesthesia is required for placement of this tube.

In Conclusion

The importance of hydration cannot be overemphasized in the treatment of kidney disease and the degree of uremia will dictate how aggressive treatment will need to be. Most patients will require a maintenance fluid therapy plan of some kind to make sure they are hydrated regularly. Your veterinarian will be able to guide you to the best fluid plan for you and your pet.

# data[].attributes.attachment_link.description
Fluid therapy concerns the administration of fluids to bring down (and keep down) the toxin levels of kidney failure. There are many ways to deliver fluids.

# data[].attributes.attachment_link.title
Working with nursing care plans- Part 2. Using the nursing care plan by Clare Main - British Veterinary Nursing Association

# data[].attributes.attachment_link.description
ABSTRACT: Nursing care plans have been used in human medical fields for a number of years and are now moving […]

# data[].attributes.body
https://www.magonlinelibrary.com/doi/abs/10.12968/vetn.2014.5.7.390

# data[].attributes.headline
Supporting quality of life in feline patients with chronic kidney disease

# data[].attributes.subject
Supporting quality of life in feline patients with chronic kidney disease

# data[].attributes.body
https://www.magonlinelibrary.com/doi/abs/10.12968/vetn.2017.8.4.200?utm_campaign=The_Veterinary_Nurse_TrendMD_0&utm_medium=cpc&utm_source=TrendMD

# data[].attributes.body
https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1748-5827.2000.tb03932.x

# data[].attributes.attachment_link.readable_text
Figure 1. Vaginoscopy reveals a conformation abnormality leading to incontinence; this is a vaginal septum caused by a persistent hymen.

Abstract

Canine urinary incontinence is a common presentation in small animal practice. The care required by the owners at home should not be underestimated as a number of these dogs are presented by owners with a request for euthanasia. Many of the causes of incontinence are treatable, so the veterinarian and veterinary nurse should perform a thorough investigation in order to obtain a diagnosis and instigate appropriate therapy. This article outlines the initial approach to an incontinent dog and discusses the specific diagnostics and treatment options available and nursing care required.

Urinary incontinence is defined as the involuntary passing of urine ( Gear and Mathie, 2011). It is a condition commonly encountered in small animal practice, and can be associated with anatomical, physical, inflammatory and neurological disorders ( Holt, 1983; Nelson and Couto, 2008). The causes of urinary incontinence are seldom life threatening, but the management of such conditions can be extremely hard work and require a lot of patience from owners. Consequently, a lot of owners request euthanasia. To prevent unnecessary and potentially premature euthanasia of an otherwise relatively healthy dog, it is important to identify the cause and any concurrent issues that may be contributing to the problem and making it worse, so that appropriate treatments may be started, and signs and symptoms eased. This should be done promptly and systematically.

To understand how a dog becomes incontinent it is important to first understand the physiology of normal micturition (the act of urinating). Urinary continence requires coordination between the urinary bladder and the urethral sphincter mechanism to allow the passive storage and active voiding of urine ( Nelson and Couto, 2008). There are two phases of micturition: the storage phase and the voiding phase.

# data[].attributes.attachment_link.title
Canine urinary incontinence: diagnosis and treatment - The Veterinary Nurse

# data[].attributes.attachment_link.description
To understand how a dog becomes incontinent it is important to first understand the physiology of normal micturition (the act of urinating). Urinary continence requires coordination between the urinary bladder and the urethral sphincter mechanism to allow the passive storage and active voiding of urine (Nelson and Couto, 2008).

# data[].attributes.attachment_link.title
Seizures in Dogs: Causes, Symptoms, and Treatments | Ultimate Dog

# data[].attributes.attachment_link.description
One in every 125 dogs will have a seizure this year. What causes these seizures will vary from dog to dog, with some episodes signaling an emergency, such as poisoning or head trauma, and others seemingly happening without reason.

# data[].attributes.attachment_link.readable_text
Abstract

It is important that veterinary professionals are able to recognise and assess pain in patients under their care. Veterinary patients cannot verbalise, or self-report on the amount of pain they are experiencing, so it is the responsibility of the professionals caring for them to be able to recognise the signs of pain, which can differ greatly between species. Once the veterinary professional has recognised the signs of pain during assessment they can then determine and appreciate the type or types of pain the patient is suffering, for example neuropathic, acute and chronic, and create an individual analgesic treatment plan. The assessment of pain in animals is for the most part based on the recognition of behavioural changes in response to pain, which cannot only vary between species but also between individuals within that species. Pain scoring systems can be utilised to quantify pain; putting a number on the level of pain for the purpose of determining whether pain exists, whether analgesia is sufficient, and in order to monitor patient progress in terms of pain management. These take into account the behavioural changes and responses of the patient and guide the user towards the calculation of a score. This article explores some of the key concepts relating to the recognition and quantification of pain, and the reliability and validity of pain scores, before considering the different pain scoring systems available for use in veterinary practice and their relative merits.

Mathews et al (2014: 5) in the World Small Animal Veterinary Association (WSAVA) guideline described pain as the fourth vital sign, and proposed the following definition of pain: 'a complex multi-dimensional experience involving sensory and affective (emotional) components. In other words, pain is not just about how it feels, but how it makes you feel, and it is those unpleasant feelings that cause the suffering we associate with pain.' Based on this description, it is clear there are going to be inherent difficulties associated with a veterinary professional being able to quantify pain in animals as veterinary patients are unable to verbalise the location of their pain or indeed how it is making them feel. This problem is similar to that found in human medicine where the professionals are attempting to recognise, assess and quantify pain in (pre-lingual) newborn and infant children, whose ability to verbally communicate is limited or indeed absent ( Bellieni, 2012). Bellieni (2012) highlighted that with these pre-lingual patients medical professionals observe and measure a number of physical and behavioural cues, and the responses they record feed into their overall judgement about levels of pain and whether the analgesic plan needs amending. These cues include:

Facial expression - brow bulging, eye squeezing, nasolabial furrow, and an open mouth are all indicators of pain, but are not necessarily exclusively associated with pain. This is similar in animals, where changes in facial expressions in a number of species are thought to be linked to pain, such as in rabbits (Keating et al, 2012), mice (Langford et al, 2010), rats (Sotocinal et al 2011) and horses (Dalla Costa et al, 2014) where 'grimace scales' have been developed and tested in research.

Body movements - arm and leg activity, more subtle clenches of their fists and toes are all indicators of pain, however it is recognised that a lack of movement and responsiveness does not mean the infant is not experiencing pain. This also links well to animals as they will often posture in certain ways in order to alleviate the pain they are feeling, or will subtly alter the way they move around and settle down to rest in relation to the pain they are experiencing (Mathews et al, 2014).

Crying - this is thought to be a sign of pain, but again the professionals recognise that it cannot be used as the sole indicator of pain as infants do cry when they are hungry or angry for example. This is similar to animals as many do vocalise when they are experiencing pain, whether that is a cry, a howl, a hiss and so on. However, some animals vocalise in this manner whether they are in pain or not for a number of different reasons. This is where it is important for veterinary professionals to ask the owners about their pet's normal behaviours as they know them best (Epstein et al, 2015), and this baseline data about the patient can inform assessment and consequent nursing interventions. Do they vocalise a lot? When do they vocalise? Have they started vocalising more than usual recently? What is the nature of the change?

Behavioural states - this relates to how quiet or alert the infant is, and also the nature of the transitions between these states. For example, excessive sleep or irritability is generally believed to be indicative of chronic pain states, but if the infant suddenly awakens or cries it can be interpreted as an indicator of acute pain. This can be related to animals as well. The owners are going to be the main source of information here, and the veterinary professionals must ask the right questions to obtain the information they require to make a judgement in relation to pain. The owners might attribute their pet sleeping more or being a little more irritable than normal to the ageing process for example, whereas it could be that the animal actually has a pre-existing condition such as osteoarthritis that is now getting rather painful; it has insidiously worsened over time rather than being an acute incident.

Physiological indicators - heart rate increase, blood pressure increase, oxygen saturation decrease and breathing pattern (rapid, shallow or irregular) variations are all often attributed to the pain response in human infants, and are measured to determine the need for analgesics in many cases. However, as in animal patients, there may well be an underlying disease condition responsible for the physiological changes detected, therefore making them less specific as pain indicators. Underlying conditions should be ruled out and physiological indicators should not be relied on as the sole indicators of pain in any species.

Biological markers - stress hormones such as cortisol and adrenaline can be measured in serum or saliva samples in human infants and animals, which have been proven to be released as part of the pain response. This is good additional data to obtain during pain assessment, however waiting for the sample analysis results to be provided limits the clinical application of these types of tests in practice; professionals cannot wait for these test results to be provided before they alter their analgesic plans for a patient in pain.

Behavioural changes associated with pain in animals can be associated with or influenced by a number of different factors which veterinary professionals must be mindful of, including:

Species - it is essential that the veterinary professional has a good working knowledge of the normal behaviour of a given species in order to be able to recognise any changes that are shown as a result of pain, which links back to the previous point about facial expressions.

Environment - a strange or unfamiliar environment can cause a marked change in an animal's behaviour such as when they are taken to a veterinary practice, which can mask behaviour changes attributable to pain.

Pain location - the actual site of the pain can also influence behavioural changes for instance it is easier to assess a painful joint than abdominal pain.

Previous conditioning - an animal will often over react to an experience that previously it found painful, for example having its nails clipped where the blood vessel was cut as it anticipates that the experience is going to be painful again.

Temperament - the temperament of the animal can also determine its reaction to pain; a naturally quiet dog will tend to become anxious, while a more dominant dog might become aggressive when in pain. Again this is very variable and influenced by many other factors; the veterinary professional must always treat patients as individuals.

Concurrent diseases - both these factors can influence an animal's normal behaviour. Many animals in practice do not potentially have an obvious reason to be in pain, however because of another disease process they are suffering, for example pancreatitis, they are significantly painful so their behaviour alters. The veterinary nurse must be mindful of, and knowledgeable about, the pathophysiology of these types of diseases to ensure they assess the animals thoroughly.

Using the Principle of Analogy is useful in veterinary patients when attempting to recognise and then assess pain; if the professional believes the disease or injury the animal has would be painful if they had the disease or injury themself, it is safe to assume the animal is in pain and analgesia is required. However, anthropomorphism and empathy, while no bad starting point for scoring pain in veterinary patients, may also adversely influence the recognition and interpretation of pain. Vocalisation for example, may lead to higher pain scores being awarded than more subtle indicators, even if the latter represent more severe pain, so veterinary professionals must be mindful of these principles when they are assessing their patients ( Nuffield Council on Bioethics, 2005). Epstein et al (2015:69) stated that 'it is now accepted that the most accurate method for evaluating pain in animals is not by physiological parameters but by observations of behaviour'. Both Mathews et al (2014) and Epstein et al (2015) emphasised that response to appropriate treatment is considered the gold standard in terms of measuring the presence and degree of pain.

Reliability - a reliable scale will give the same score if used in many individuals with similar levels of pain, or the same individual when observed by many people.

Sensitivity - a scale needs to be sensitive in order to detect small variations.

Validity - this can be proven by demonstrating that the system is measuring what it is supposed to, and nothing else.

Simple descriptive scales (SDS), as the name suggests, are the most basic, usually with 3 to 5 grades to choose from, each defined by a short description. The observer watches the patient, handles it and interacts with it, and palpates around a wound for example before assigning a score (Tables 1 and 2). It is perfectly possible to combine more than one SDS scale based on different parameters, behaviours or observations and add the scores together. Scales of this sort are easy enough to use, but are very subjective, and large variations in scores can be given for all the reasons discussed earlier. The quest for user friendliness may also risk over simplification, and consensus about the number of distinct points needed does seem hard to reach.

Visual analogue scales (VAS) employ a line, often 100 mm long, where one end represents no pain at all, the other the worst possible pain (Figure 1). The observer marks a point on the line to correspond with the assessed pain level. No cues are provided for the observer, as the line is not marked off numerically, and the system can be made more relevant by qualifying the one extreme as the worst pain for that particular procedure or condition. The patient is, however, just observed in the kennel or cage, with no interaction or examination involved. This does seem to be a quite sensitive method, and it allows for finer graduation than a SDS, but does still rely on the observer's judgement, which is inevitably subjective. Recording is also apparently affected by the observer's visual and motor co-ordination, which may reduce the ability to accurately place the mark on the line. Observers must be well-trained in the use of such a scoring system, which really provides very little in the way of inbuilt guidance as to what constitutes what (Crompton, 2010).

Numerical rating scales (NRS) are similar to VAS but the observer is asked to choose a number rather than simply marking a point on a line (Figure 2). This system is again more sensitive than an SDS, and may be a good compromise between the lack of sensitivity of an SDS and the unreliability of a VAS, though there still may be considerable variability.

Table 1. Example simple descriptive scale (SDS) for cats

Score

Description

0

No pain, no overt signs of discomfort and no resentment to firm pressure

1

Some pain, no overt signs of discomfort but resentment to firm pressure

2

Moderate pain, some overt signs of discomfort which are made worse by firm pressure

3

Severe pain, obvious signs of persistent discomfort which are made worse by firm pressure

( Grant, 2006)

Table 2. Example simple descriptive scale (SDS) for dogs

Observation

Score

Criteria

1

Vocalising, responds to calm voice and stroking

2

Vocalising, does not respond to calm voice and stroking

1

Frequent position changes

2

Thrashing

1

Mild agitation

2

Moderate agitation

3

Severe agitation

( Grant, 2006)

Figure 1. An example of a visual analogue scale (VAS).

Figure 2. An example of a numeric rating scale (NRS).

Dynamic and interactive visual analogue scales (DIVAS) are a form of modified VAS. The patient is observed at rest, then handled, palpated and walked out before a mark is once more made on a linear scale; hence the 'dynamic and interactive' part of its name. This does overcome some of the deficiencies of a simple VAS which may fail to recognise pain in an animal that was just lying still. VAS and DIVAS are considered to be more accurate than a SDS (Crompton, 2010).

Variable rating scales (VRS) include objective physiological data such as heart rate, respiratory rate, pupil size and rectal temperature, as well as spontaneous behaviour, interactive behaviour, response to palpation, mental status and vocalisation. The observer assigns a number from the scale to the patient according to definitions or descriptors provided. These individual scores are then added up to give an overall pain score for that patient (Crompton, 2010) (Table 3).

Table 3. Example variable rating scale for use in dogs

Variable

Criteria

Score

11-30% greater than pre-op value

1

31-50% greater than pre-op value

2

>50% greater than pre-op value

3

Mild abdominal assistance

1

Marked abdominal assistance

2

Crying, responsive to calm voice

1

Crying, does not respond to calm voice

2

Mild agitation

1

Moderate agitation

2

Severe agitation

3

Minimal response, tries to move away

1

Turns head towards site, slight vocalisation

2

Turns head with intention to bite, howls

( Grant, 2006)

SDS for dogs

Acute (multi-dimensional) cat

Acute (multi-dimensional) dog

Chronic (multi-dimensional) dog.

All veterinary practices should aim to adopt a species-specific and pain typespecific tool for pain assessment in their patients.

One-dimensional pain scales have their place in veterinary practice if they are used consistently, and the numerical rating scale is the recommended scale of this type.

Mulit-dimensional/composite pain scales are preferable over one-dimensional varieties as they are able to assess more facets of the pain experience, and practitioners should aim to use a validated scale.

# data[].attributes.attachment_link.title
Pain scoring systems in the canine and feline patient - The Veterinary Nurse

# data[].attributes.attachment_link.description
Increased recognition of the significance of animal pain and the necessity to control it has led to veterinary professionals looking to human medicine for guidance in how to quantify pain, a notoriously difficult task due to the subjectivity of pain experiences.

# data[].attributes.attachment_link.readable_text
The patient presented with a 2-day history of vomiting, anorexia and lethargy. On admission, she was trembling and panting. There was a previous history of a gastrointestinal foreign body.

Signalment

Species: Canine

Breed: Labrador crossbreed

Age: 11 years 11 months

Sex: Female neutered

Weight: 23.6 kg

Patient assessment

On physical examination, the patient was quiet and lethargic but responsive. Her mucus membranes were pink and moist and capillary refill time was two seconds. The patient was tachycardic and panting. Her temperature was 38.9°C and she experienced pain on abdominal palpation.

Veterinary investigations

The veterinary surgeon requested a comprehensive blood profile including electrolytes, haematology, biochemistry and a canine pancreatic lipase (cPLI) test. The cPLI was abnormal, her urea was 11.9 nmol (1.70-7.40 nmol), alkaline phosphatase (ALKP) was 580 nmol (12-83 nmol) and phosphate was 2.50 nmol (0.80-1.80 nmol). The veterinary surgeon diagnosed acute pancreatitis, but the presence of a gastrointestinal foreign body could not be ruled out. Supportive treatment, including intravenous (IV) fluid therapy, analgesia, antacids and antiemetics, was initiated.

Two hours following admission, the patient's condition deteriorated; an ultrasound and radiograph were carried out. At this stage, the patient was believed to be in the early stages of septic shock resulting from septic peritonitis.

Discussion of nursing interventions

Sepsis is an inflammatory condition resulting from bacterial contamination, and is commonly observed following perforation of the gastrointestinal tract by a foreign body ( Swayne et al, 2012). Sepsis is potentially fatal; if left undiagnosed, secondary multi-organ dysfunction is likely to occur, resulting in death ( Bentley et al, 2007).

When the body identifies an infection, a controlled inflammatory response is established to eliminate the invading pathogen ( Breton, 2012). The inflammatory cascade is a mediator-driven system. It begins when immune cells are activated as a result of cell injury to produce cytokines, which act as mediators in the inflammatory cascade. These mediators can be classified as pro or anti inflammatory, and they have different effects at different stages ( Aldrich, 2007). Cytokines are produced by macrophages and are activated in response to cell injury. Tumour necrosis factor and interleukin 1 are the main pro-inflammatory cytokines. When these are released into the body, clinical signs such as anorexia, hypotension, pyrexia and tachycardia can be seen ( Aldrich, 2009). This is termed the systemic inflammatory response syndrome (SIRS) ( Mittleman Boller and Otto, 2009) ( Figure 1).

Figure 1. Disease process from trauma to septic shock (adapted from Mittleman Boller and Otto (2009); Breton (2012)). SIRS, systemic inflammatory response syndrome; HR, heart rate; RR, respiration rate.

In 1997, Hauptman et al conducted a study to establish the specific parameters indicative of canine SIRS. They concluded that, when a patient has two or more of the following clinical signs, SIRS can be confirmed: a heart rate over 160 beats per minute; a respiration rate above 20 respirations per minute; a body temperature of less than 37.8°C or more than 39.7°C; and a white blood cell count of less than 4 000 or more than 12 000. Using these parameters, it can be concluded that the patient in this study was positive for a SIRS.

Multiple elements must be considered when nursing a patient in septic shock. These include: administering antibiotic and analgesic regimens based on vital signs monitoring and pain assessments; implementing advanced monitoring including blood testing; and blood pressure monitoring to ensure adequate fluid therapy. Finally, behavioural changes, the ability to urinate and defecate, and comfort for recumbent patients should be considered ( Lanz et al 2001; Crompton and Hill, 2011; Breton, 2012).

The patient was nursed intensively before surgery and this study focuses on fluid therapy, pain assessments and basic monitoring.

Basic monitoring

In 2012, Breton stated that septic patients should be assessed every 4-6 hours, and this should include evaluations of heart rate, respiration rate and effort, temperature, mucous membrane colour, capillary refill time and behavioural changes.

The patient was monitored every 30 minutes for the first 3 hours and hourly thereafter. She began to deteriorate, showing early signs of septic shock - tachycardia, increased systemic blood pressure, brick red mucous membranes and fever. The later stages of sepsis lead to tachypnea, severe hypotension, depression and multi-organ dysfunction. Therefore, the author recommends that basic vital signs should be monitored every 15-30 minutes in unstable septic patients.

Breton (2012) identified that blood glucose monitoring is important in septic patients, considering that hypoglycaemia is a concern because of anorexia. Breton (2012) further stated that, although once daily monitoring is acceptable, more frequent monitoring is recommended should hypoglycaemia be suspected. In this case, doing this was not considered; further monitoring of glucose levels could have provided the veterinary surgeon with valuable information and led to the administration of IV dextrose which may have proved beneficial to the patient.

Septic patients can quickly progress to shock, and blood pressure (BP) monitoring can be used to identify hypoperfusion and hypotension. The patient was hypertensive, which is unexpected in shocked patients; changes in BP are detected by baroreceptors and hypertension leads to compensatory peripheral vasodilation ( Boag and Hughes, 2005). Other factors, particularly pain, can lead to a high BP ( Pachtinger, 2013). Since compensated shock may produce parameters that are not noticeably abnormal, BP monitoring must be carried out frequently to detect the decompensated stages ( Porter et al, 2013). The patient's BP was monitored once; in hindsight, she could have benefited from further readings.

BP monitoring can be implemented using indirect methods including using a Doppler flow monitor ( Figure 2) or an oscillometric device ( Figure 3), or direct techniques using arterial blood pressure measurements ( Bosiack et al, 2010). A Doppler flow monitor was used to monitor this patient's BP; direct techniques are seen as gold standard for care since they allow trends in pressure changes to be closely monitored ( Pachtinger, 2013). Most patients, however, will not tolerate catheter placement unless anaesthetised or critical so catheters are unsuitable for most conscious patients ( Clapham, 2011).

Figure 2. An example of a Doppler flow monitor.

Figure 3. Example of an oscillometric device monitor.

The detection of the pulse in the Doppler method can be subjective and therefore open to inconsistences so must be interpreted alongside other parameters measured ( Clapham, 2011). Bosiack et al (2010) compared indirect and direct BP monitoring techniques in 11 dogs. Although only a small sample group was used, they concluded that the indirect methods did not meet the validation standards set out in human medicine, and that direct techniques were more accurate. They suggested that inconsistencies in indirect techniques were due to incorrect cuff selection and patient preparation. Practices should ensure nurses are adequately trained in using indirect techniques given their common use in first opinion practice ( Clapham, 2011).

The patient's temperature was closely monitored throughout her stay. On admittance, her temperature was 39.9°C. This increased to 41°C, at which point a fan was used to reduce her temperature. A high temperature can cause tachycardia, tachypnea, panting and tacky, red mucus membranes ( Mann, 2012). Pachtinger (2013) identified the importance of dfferentiating between hyperthermia and fever. Hyperthermia is seen following exogenous causes such as a rise in environmental temperature, and an increase in muscle activity, for example during exercise. Fever occurs following endogenous causes such as infection, inflammation or neoplastic processes.

Therefore, patients presenting with hyperthermia require active cooling measures when temperatures exceed 40°C. Those with fever, however, should not be cooled and the underlying cause should be treated. Cooling a patient with fever can lead to vasoconstriction, which can reduce heat loss ( Mann, 2012). Using a fan on this pyrexic patient may have prevented appropriate heat loss and, in hindsight, should not have been used. Following analgesia, antibiotics and fluid therapy, her temperature started to decrease.

Pain assessment

Pain assessment in a patient with sepsis should be carefully considered, as correct regimens to treat it can help reduce the likelihood of morbidity and mortality ( Murphy and Warman, 2007). Opioids are an appropriate choice in treating acute abdominal pain.

The patient was given two injections of methadone at a dose of 0.3 mg/kg 3 hours apart, but remained in pain. Multimodal analgesia seems to be the most effective method of treating chronic pain, but studies in acute pain are limited ( Flaherty, 2013). Abdominal pain is activated by a stimulus such as penetration by a foreign body or an organ stretching. Free nerve endings called nociceptors are activated and an electrical signal is transmitted to afferent nerve fibres via an action potential. A and C nerve fibres exist to transmit the stimuli to the spinal cord, then to the brain ( Mazzaferro, 2003). A fibres transmit fast, immediate pain and C fibres transmit slow pain in the form of a dull ache ( Bloor, 2012). Since the pathophysiology of abdominal pain is complex, it could be argued that multimodal analgesia has its place in management of acute pain ( Flaherty, 2013). Bloor (2012) stated that pain management should be classified as the fourth vital sign, since its effects on a patient's stress levels and recovery can be dramatic.

Pain assessment can be difficult, since response to painful stimuli can vary between individuals. Therefore, a holistic approach should be adopted, including detailed hospital forms, care plans and pain scoring charts. As pain can have detrimental effects on wellbeing, it is imperative that veterinary nurses can assess and identify changes in a patient's ability to eat, sleep, drink and express normal behaviour ( Bloor, 2012). A care plan ( Table 1) and a hospital chart, covering specific requirements and vital signs, were used when this patient was being nursed. These allowed pain to be identified and a second analgesic dose administered.

Table 1. Nursing care plan

Patient's name .................................................   Date........................................Age: 4 years   Time: 9:30am    VS:    VN:    ID No:To be completed once daily or more often following dramatic changes in patient's health or following surgery

ABILITY

Normal routine

Grade

Problem list

NURSING INTERVENTIONS (detail on hospital form with times)

Review time/frequency

Evaluation

KEY: Grade: 0 = normal 1 = minor 2 = moderate 3 = major

A pain score chart was not used for this patient. Morton et al (2005) demonstrated that a such a scale is a valid method of pain assessment in dogs. In 2007, Coleman and Slingsby stated that veterinary nurses agreed that pain scales were a useful clinical tool. The use of a pain score chart in this case may have led to the analgesia regimen being altered to manage pain more effectively.

Fluid therapy

IV fluid therapy plays an important role in the management of the septic patient. Septic shock is a form of distributive shock in which there is a loss of systemic vascular resistance. The patient was initially placed on Hartmann's isotonic crystalloid fluid on twice maintenance (maintenance being 2 ml/kg/hour) to correct dehydration and electrolyte imbalances. The fluid rate was increased to three times maintenance when the patient began to deteriorate to reduce temperature and heart rate. Although the patient was hypertensive, the fluid rate remained high in an attempt to try to correct the signs of shock.

Fluid therapy is used in septic patients to treat hypovolaemia, hypoperfusion and hypotension ( Pachtinger and Drobatz, 2008). In septic patients, there is an intravascular fluid deficit. For crystalloids to be given effectively in shocked patients, the rate must be high enough to account for the fact that 75% of the solution administered rapidly shifts from the intravascular space into extravascular space. Traditionally, the shock rate for dogs was 90 ml/kg given in increments over 20-30 minutes ( Pachtinger and Drobatz, 2008). More recently, it has been suggested that smaller volumes of 20-30 ml/kg should be administered over 20 minutes since larger volumes may affect coagulation.

Patient assessment should be performed after each bolus of IV fluid therapy to assess the need for further boluses or placement onto maintenance rates ( Mazzaferro and Powell, 2013). Assessment of the effects of IV fluid therapy is usually the role of the veterinary nurse, and monitoring vital signs can help identify if the rate needs to be changed. Alongside IV fluid therapy, nurses must monitor urine output to ensure patients do not become over or under infused. It was noted during the patient's treatment when urination occurred; however, volume was not recorded. Considering Mazzaferro and Powell's (2013) guideline, the patient could have been placed on a higher fluid rate and, had urine output been specifically measured, the veterinary team may had more information on which to base decisions about the correct fluid rate.

Future considerations

One topic highlighted in the study was that pain scoring could be used better within the practice. Although available to the staff, they are not routinely used. While pain scoring has been increasingly implemented in recent years, very little evidence is available to prove its usefulness to veterinary nurses. Since analgesia can often be overlooked, it is vital that nurses are not only able to recognise signs of pain in patients but are also able to document this as evidence. In 2007, Coleman and Slingsby conducted a study into the attitudes of veterinary nurses to pain assessment and the use of pain scales. They found that 80.3% agreed that pain scales were useful but only 8.1% used them routinely in practice. Nearly all (96%) of the nurses felt they could improve their knowledge of pain management.

Coleman and Slingsby (2007) also found that veterinary nurses who had been qualified for longer tended to assign higher pain scores than those with less experience. While it was suggested that this could be down to their greater nursing experience, it does highlight the need for nurses to be educated in this area. One starting point should be the inclusion of pain scoring in student nurse training.

Conclusion

This study demonstrates the importance of veterinary nurses understanding the pathology of diseases. Although clinical judgments are the concern of the veterinary surgeon, the role of the nurse remains at the forefront of care. Recognising improvements or deteriorations in a patient's wellbeing and vital signs allows nursing care to be tailored individually.

The care of a septic patient can be challenging, so veterinary nurses must ensure they keep up with changes in medical nursing to ensure their techniques are relevant and up to date. Practices may not always be fitted with the most advanced equipment, but simple techniques can be introduced routinely to improve patient care.

Key Points

Sepsis is potentially fatal: unrecognised it can lead to secondary multi-organ dysfunction resulting in high mortality rates.

Understanding the pathophysiology of septic shock is vital to ensure care is specifically tailored to the patients individual needs.

Pain management should be classified as the fourth vital sign.

Fluid therapy is used in septic patients to treat hypovolaemia, hypoperfusion and hypotension.

Basic monitoring is used by veterinary nurses to spot trends in a patient's recovery, so care can be tailored quickly and effectively.

# data[].attributes.attachment_link.title
Nursing a canine in septic shock: a patient care report - The Veterinary Nurse

# data[].attributes.attachment_link.description
The patient presented with a 2-day history of vomiting, anorexia and lethargy. On admission, she was trembling and panting. There was a previous history of a gastrointestinal foreign body.

# data[].attributes.attachment_link.title
Physiotherapy Improves Dogs’ Quality of Life Measured with the Milan Pet Quality of Life Scale: Is Pain Involved?

# data[].attributes.attachment_link.description
Recent scientific evidence highlights the importance of assessing quality of life in veterinary patients. Quality of life reflects the well-being of animals from the physical, psychological, and social point of view, as well as the safety and freedom…

# data[].attributes.attachment_link.readable_text
Physical rehabilitation for veterinary patients expedites return to normal function, pain relief, and encouragement of optimal health for patients suffering from orthopedic, neurologic, and chronic diseases. Patients that use rehabilitation programs range from overweight pets and those recovering from injuries and surgeries to senior pets with chronic, debilitating conditions and agility, field trial, hunting, and service dogs.

Physical rehabilitation can be an invaluable addition to a veterinary practice with relatively low overhead costs. This article provides an overview of physical rehabilitation modalities and focuses on incorporating these modalities into practice; a follow-up series on physical rehabilitation modalities will provide further information on indications for certain therapies, training for veterinary staff, and treatment plans for patients.

Cryotherapy

Description

Cryotherapy (or cold therapy) is the application of a cold agent to an affected area of the body, such as a surgical site, to provide therapeutic effects by reducing tissue temperature. Research has shown that cryotherapy is effective in the first 72 hours after acute injury or surgery. ¹

Benefits

Cold therapy provides:

Analgesia

Vasoconstriction

Decreased blood flow to the affected area

Reduced cellular metabolism

Reduction in edema, muscle spasms, and initial immune response to injury or surgery²⁻⁴

Indications

Indications for use of cold therapy include any injury or procedure that causes inflammation, pain, or decreased range of motion and neurologic disorders, such as spasticity. 2,3 Specific surgical procedures where cryotherapy is indicated postoperatively for pain and swelling include:

Femoral head and neck ostectomy⁵

Tibial plateau leveling osteotomy (TPLO)6,7

Tibial tuberosity advancement (TTA).

Additional disorders where cryotherapy is used to address pain and inflammation include:

Tendon and ligament injuries⁵

Fracture repair⁸

Osteochondritis dissecans (OCD)

Osteoarthritis.⁹

Implementation

Cold agents may include ice, gel packs, cold compression devices, multiple towels immersed in ice water, or simply a bag of frozen vegetables. ²

Ice or Gel Pack : When using a plastic bag filled with ice or a gel pack, cover it before application with a thin, wet layer of fabric to improve temperature exchange between the tissue and cold agent. Do not use a thick layer of fabric, such as a towel or blanket, because therapeutic temperatures may not be reached in deep tissues. ²

Towels in Ice Water: Multiple towels must be used because a single towel will not maintain adequate therapeutic temperatures long enough to be effective. An effective method of using towels is to immerse 2 towels in ice water and alternate application when the towel being used becomes too warm for therapeutic effectiveness. ²

Cold Compression Devices : These devices are commercially available and use a combination of controlled pressure with a continuous flow of cold water to help minimize swelling and pain postoperatively.

Heat Therapy

Description

Heat therapy is used to achieve effects opposite to those of cryotherapy; however, both modalities are used to provide analgesia and decrease muscle spasms. ² Since cold therapy should be performed for the first 72 hours, heat therapy should only be initiated after 72 hours and continued for a period based on the individual patient, typically 5 to 7 days. Beginning heat therapy too early can lead to worsening edema, swelling, and potential seroma formation.

Benefits

Heat therapy provides:

Analgesia

Decreased muscle spasms

Increased impulse conduction and fibrous tissue elasticity

Vasodilation

Decreasing blood pressure if heat is applied for long periods of time.2,3

Indications

Indications for heat therapy include:

Chronic inflammation

Decreased range of motion

Pain

Muscle tension

Preparation for additional exercises including stretching and therapeutic ultrasound.2,3

Specific procedures or disorders that benefit from heat therapy include:

Cranial cruciate ligament (CCL) rupture

Fracture repair⁸

OCD management

Tendon and ligament injury management⁵

Neurologic disorders, such as intervertebral disk disease (IVDD)¹⁰

Osteoarthritis⁹

Spondylosis.⁵

Implementation

The best way to incorporate heat therapy in private practice is to use superficial heating agents that transfer heat to affected tissues.

Superficial heating agents include hot packs, heat wraps, towels immersed in hot water, and application of warm water. 2,3 Many of these items can be found in pharmacies.

Hot/Warm Packs: Most hot packs contain gel of some type that can be reheated and reused many times. ² The veterinarian or technician conducting therapy should heat the pack in a microwave or boiling water to a temperature tolerated by the therapist's skin. A hot pack should never be placed directly on the skin or incision site, but should be placed in a cloth or towel prior to application. ³

Heat Wraps: Heat wraps are used to provide analgesia. Some products claim to provide up to 8 hours of heat and can be adjusted to fit most dogs and cats. ² Caution should be taken when leaving these applied as they may cause skin burns.

Towels in Hot Water: Use of towels immersed in hot water is a modality that can be easily performed. Multiple towels should be immersed in hot water, put in a plastic bag, and placed on the affected area. Towels must be alternated to maintain therapeutic temperatures. Another method is to dampen the towel and warm it in the microwave.

Warm Water Application: Warm water application is performed by filling a bathtub with warm water and placing the patient in the tub, taking special care to not allow the patient's head to submerge. ³ Water temperature should be warm, typically 90°F to 95°F, but lower if exercises will be performed in order to avoid overheating. Do not submerge fresh surgical incisions until they have healed.

Passive Range of Motion

Description

Passive range of motion (PROM) refers to exercises that move joints through their available range of motion without weight bearing muscle contraction. 3,11,12

Benefits

PROM provides:

Prevention of joint and muscle contracture

Analgesia

Increased blood flow and lymphatic flow

Increased synovial fluid production to decrease articular cartilage degradation11,12

Prevention of joint degeneration and muscle contracture during the acute rehabilitation phase for patients undergoing hemilaminectomy to treat IVDD.

PROM, however, will not prevent muscle atrophy or increase strength or endurance.

Indications

Indications for PROM are most commonly related to surgical procedures or soft tissue injuries to extremities where active weight bearing is prohibited. Other indications include paralyzed animals. 3,12
PROM provides therapy for specific disorders, such as:

Loss of full range of motion¹³

CCL rupture stabilization using TPLO¹⁴ or TTA

Hip or shoulder disorders¹⁵

Fractures⁸

Distal femoral physis fractures in juveniles.⁵

Implementation

Comfort is of the utmost importance when performing PROM therapy.

The patient should be placed in lateral recumbency on a soft, padded surface, or allowed to stand comfortably.

The therapist should grasp the limb above and below a joint, but close to the joint to reduce the forces placed on it.3,11 The joint should be slowly and gently flexed and extended to the full limit of the patient's range of motion (Figure 1). All joints in the limb should be flexed and extended to achieve full therapeutic benefit.

Additionally, adduction and abduction of the limb may also be performed to provide PROM to the shoulder and hip joints. Manipulation of the full limb in sequence, in a motion similar to riding a bicycle, allows PROM of all joints and tissues.3,11 This motion should be slow and steady.

PROM exercises are typically performed for 15 to 20 minutes, up to several times a day, depending on the indication.

Balance Therapy

Description

Weight shifting can be used to improve balance once the patient has regained the ability to stand on its own or with the assistance of a sling or therapy ball ( Figure 2). This therapy is focused on helping the animal understand that the affected limb(s) is no longer painful.

Benefits

Weight shifting exercises:

Increase muscle mass

Improve proprioception

Allow early return to function¹¹

Rebuild core muscle strength.

Indications

Indications for weight shifting therapy include:

Loss of proprioception

Muscle atrophy

Pathologic weight shifting.¹⁶

Therapy is beneficial for specific disorders, such as:

Loss of proprioception and balance

Neurologic disorders that affect limb function⁹

Loss of weight bearing due to fractures⁸ or wounds

Immobilization of a limb after ligament repair (eg, CCL).5,16

Implementation

Weight shifting therapy is performed by placing the animal on a nonslick surface in a standing position.

The therapist places his or her hands on the animal's side and gently helps the patient shift its weight from side to side and front to back, encouraging use of the affected limb or muscles in a controlled manner.

If the patient is unstable when standing, a sling or exercise ball may be placed under its abdomen or thorax to provide support. 3,11

If the patient is stable, the therapist can allow the patient to become slightly off balance by gently pushing the patient's hip or shoulder or lifting the normal limb. The patient must correct its balance by shifting weight to the affected limb.3,11,16

Balance or wobble boards may also be used to improve balance and proprioception. ¹³ The patient's forelimbs or hindlimbs are placed on the board and swayed back and forth to encourage weight shifting from side to side or front to back. A larger board allows all four limbs to be placed on the board ( Figure 3). 3,16,17

Walking Exercises

Description & Benefits

Walking exercises are essential to any animal's rehabilitation program. Walking exercises provide:

Increased range of motion

Improved gait, muscle mass, and strength

Improved circulation in blood and lymphatic vessels

Increased endurance

Prevention of joint degeneration.16,18

Indications

Walking exercises are indicated early in rehabilitation for animals refusing to use their affected limb due to muscle weakness, decreased range of motion, circulation disorders, neurologic deficits, and proprioceptive deficits. 16,18
Walking exercises may improve specific disorders, including:

Stabilized fractures⁸

Surgically repaired joint disorders,19,20 such as OCD lesions

Femoral head and neck ostectomy¹⁹

Stifle joint disorders, such as CCL rupture repaired by TPLO²⁰⁻²²

Soft tissue injuries, such as superficial or deep digital flexor tendon rupture.²³

Implementation

Leash walking can be performed once the patient's ambulatory status permits exercise. To begin, the patient should be walked slowly to allow the patient adequate time to place each limb on the ground and shift its weight to that limb. As the patient improves and increases strength in the affected limb, the therapist may increase the walking speed and eventually allow running while still on a leash. 2,16 Running off leash should not occur until fractures have healed or proprioceptive deficits have improved, which can take weeks to months.

Stairs/Incline: Walking up a gradual incline or short flight of stairs helps increase mass and strength of the hindlimb muscles as well as improve flexion, extension, and range of motion. The patient may initially be led up and down a flight of stairs with 2 or 3 steps, with the number of steps increased as the patient improves. 3,16

Weight Shifting: For stronger patients, weight shifting can be combined with walking exercises. Walking patients in large circles will make the interior legs carry more weight. Walking in a figure-8 pattern will shift weight on all 4 legs and increase the amount of body weight carried on each leg.

Sit-To-Stands: Sit-to-stands can be performed and build the quadriceps and hamstrings. For maximum benefit, the dog must sit with both legs under its rump. This can be encouraged by performing sit-to-stands with the animal between the therapist's legs or by having the dog sit in the corner or against a wall ( Figures 4 and 5).

Cavalletti Rails

Description & Benefits

Cavalletti rails are rails that are raised above the ground a certain distance for patients to walk over ( Figure 6). 3,11,16 Benefits of cavalletti rails include increasing stride length, range of motion, proprioception, balance, and limb use. 3,16

Indications

Indications for cavalletti rails include:

Orthopedic injuries, such as fractures and ligament ruptures

Loss of proprioception in neurologic patients

Joint and muscle pain

Decreased range of motion

Gait abnormalities

Non-weight-bearing limb(s).

Cavalletti rails are specifically indicated for:

OCD

Elbow dysplasia5,16

Total hip replacement¹⁹

Femoral head ostectomy

Fractures requiring immobilization⁸

Severe muscle atrophy

Rehabilitation after neurologic injuries.¹⁰

Implementation

Rails should be placed at different distances and heights based on the animal's disorder, goals for treatment, and patient's ability. The pace the animal is walked over the rails determines the cardiovascular component of the exercise, height determines range of motion in the joints, and distance between the poles dictates the proprioceptive challenge.

The patient should walk slowly through the rails initially. Speed, duration of therapy, and changes in elevation and length between the rails can be made once the patient becomes acclimated. Increases in height and distance between rails will increase the flexion and extension of the limbs and help increase proprioception and awareness. 3,11,16

Land Treadmills

Benefits

Goals for treadmill walking are aimed at reducing pain, making the patient bear weight on the affected limb to strengthen muscles, increasing proprioception and range of motion, producing a normal gait, and providing cardiovascular and endurance benefits. 3,11,16

Indications

Indications for treadmill walking include:

Orthopedic injuries

Decreased range of motion

Muscle atrophy

Abnormal gait

Decreased proprioception.

Specific disorders that may benefit from treadmill walking include:

Painful hips due to hip dysplasia⁵

Disuse of a limb due to surgical repair of fractures⁸

Ruptured ligaments, such as CCL ruptures²⁰⁻²²

Neurologic disorders that cause loss of proprioception, balance, and limb function.⁹

Implementation

Canine treadmills can be purchased from numerous veterinary equipment providers. Prices range from just under a thousand dollars to a few thousand dollars. Human treadmills are less expensive, ranging from a few hundred to a few thousand dollars. Modification of human treadmills for small animal patients can include addition of side walls and a brace to which a harness can be attached to support the patient if they fall. ¹⁶

Treadmills should be used carefully, with at least 2 handlers and a leash ( Figure 7). The handlers may position themselves in front of the patient to encourage forward motion and behind, above, or beside the patient to provide support, and possibly aid in gait and range of motion. 3,16

Training is important and usually successful in a short period of time. Speeds should be started off slow, generally less than 1 mph, until the animal has adapted. Some treadmills also have elevation settings; incline walking can help increase strength and range of motion. ¹⁶ Sessions can last from a few minutes to more than 30 minutes, especially in cases where endurance is a goal.

Hydrotherapy

Description

Water is effective as a rehabilitation tool due to its buoyancy, which results in an effect of decreased weight. 3,24 Water's hydrostatic pressure, where water is exerted equally on all surfaces of the object immersed, also provides an optimal environment for rehabilitation. These forces of water reduce the weight being supported by the patient's limbs, allowing them to ambulate and perform specific exercises more easily than outside a buoyant environment.

Benefits

Benefits of hydrotherapy include:

Reduction in edema and fluid pooling due to hydrostatic forces

Improved muscle mass and strength due to resistance of water

Improved range of motion

Increased endurance, weight loss, and decreased pain.²⁴

Indications

Indications for hydrotherapy include:

Orthopedic disorders

Neurologic disorders

Muscle atrophy

Decreased joint function and range of motion.3,24

Specific disorders where hydrotherapy is indicated include:

Implementation

Most veterinary practices have a large bathtub.

Fill the tub with water to a level determined by the size of the patient and affected limb.

Place the patient in the tub and allow them to walk around (Figure 8).

The therapist may stand at the head of the tub and entice the patient to move around by offering treats or playing with a ball or toy.3,24

Canine life vests are commercially available, but do not replace the need for constant supervision while the patient is in the tub (Figure 9).

Based on one study, when water levels are filled to the level of the hip and shoulder, the animal only bears 38% of its body weight on its limbs. ²⁴ However, lowering the water level creates resistance and increases the amount of work the legs perform, building muscle strength.

If the patient has access to a pool or pond, these may also be used for walking or swimming once the patient becomes adapted to hydrotherapy.

Tailoring Rehabilitation

Rehabilitation is an essential aspect of the recovery plan for small animal patients. Protocols should be tailored for the individual patient based on its disorder and the goals desired from rehabilitation. All therapy sessions take patience and practice; some exercises or modalities may work better for different patients' temperaments and specific conditions. Rehabilitation changes as the animal improves and recovers; the therapist must be educated about physical rehabilitation, creative and flexible with protocols, and adjust them for each situation.

CCL = cranial cruciate ligament; IVDD = intervertebral disk disease; OCD = osteochondritis dissecans; PROM = passive range of motion; TTA = tibial tuberosity advancement;
TPLO = tibial plateau leveling osteotomy

References

1. Shumway R. Rehabilitation in the first 48 hours after surgery. Clin Tech Small Anim Pract 2007; 22(4):166-170.

2. Steiss JE, Levine D. Physical agent modalities. Vet Clinics North Am Small Anim Pract 2005; 35:1317-1333.

3. Bockstahler B, Millis D, Levine D, et al. Physiotherapy-what and how. Essential Facts of Physiotherapy in Dogs and Cats: Rehabilitation and Pain Management. Germany: BE Vet Verlag, 2004, pp 46-123.

4. Heinrichs K. Superficial thermal modalities. In Millis D, Levine D, Taylor RA (eds): Canine Rehabilitation and Physical Therapy. Philadelphia: Saunders Elsevier, 2004, pp 277-288.

5. Bockstahler B, Millis D, Levine D, et al. Indications: Classifications according to location. Essential Facts of Physiotherapy in Dogs and Cats: Rehabilitation and Pain Management. Germany: BE Vet Verlag, 2004, pp 126-286.

6. Rexing J, Dunning D, Siegel AM, et al. Effects of cold compression, bandaging, and microcurrent electrical therapy after cranial cruciate ligament repair in dogs. Vet Surg 2010; 39(1):54-58.

7. Drygus KA, McClure SR, Goring RL, et al. Effect of cold compression therapy on postoperative pain, swelling, range of motion, and lameness after tibial plateau leveling osteotomy in dogs. JAVMA 2011; 238(10):1284-1291.

8. Doyle ND. Rehabilitation of fractures in small animals: Maximize outcomes, minimize complications. Clin Tech Small Anim Pract 2004; 19(3):180-191.

9. Sulka KA, Christy MR, Peterson WL, et al. Reduction of pain-related behaviors with either cold or heat treatment in an animal model of acute arthritis. Arch Phys Med Rehabil 1999; 80(3):313-317.

10. Drum MG. Physical rehabilitation of the canine neurologic patient. Vet Clin North Am Small Anim Pract 2010; 40:181-193.

11. Fossum TW, Hedlund CS, Johnson AL, et al. Small Animal Surgery. Philadelphia: Mosby Elsevier, 2007, pp 111-129.

12. Millis DL, Lewelling A, Hamilton S. Range-of-motion and stretching exercises. In Millis D, Levine D, Taylor RA (eds): Canine Rehabilitation and Physical Therapy. Philadelphia: Saunders Elsevier, 2004, pp 228-243.

13. Saunders DG. Therapeutic exercise. Clin Tech Small Anim Pract 2007; 22(4):155-159

14. Monk ML, Preston CA, McGowan CM. Effects of early intensive postoperative physiotherapy on limb function after tibial plateau leveling osteotomy in dogs with deficiency of the cranial cruciate ligament. Am J Vet Res 2006; 67(3):529-536.

15. Marcellin-Little DJ, Levine D, Canapp Jr SO. The canine shoulder: Selected disorders and their management with physical therapy. Clin Tech Small Anim Pract 2007; 22(4):171-182.

16. Hamilton S, Millis DL, Taylor RA, et al. Therapeutic exercises. . In Millis D, Levine D, Taylor RA (eds): Canine Rehabilitation and Physical Therapy. Philadelphia: Saunders Elsevier, 2004, pp 244-263.

17. Marcellin-Little DJ, Levine D, Taylor R. Rehabilitation and conditioning of sporting dogs. Vet Clin North Am Small Anim Pract 2005; 35:1427-1451.

18. Dunning D, Halling KB, Ehrhart N. Rehabilitation of medical and acute care patients. Vet Clin North Am Small Anim Pract 2005; 35:1411-1426.

19. Edge-Hughs L. Hip and sacroiliac disease: Selected disorders and their management with physical therapy. Clin Tech Small Anim Pract 2007; 22:183-194.

20. Marsolais GS, McLean S, Derrick T, et al. Kinematic analysis of the hind limb during swimming and walking in healthy dogs and dogs with surgically corrected cranial ligament rupture. JAVMA 2003; 222(6):739-743.

21. Jerre S. Rehabilitation after extra-articular stabilization of cranial cruciate ligament rupture in dogs. Vet Comp Orthop Traumatol 2009; 22(2):148-152.

22. Marsolais GS, Dvorak G, Conzemius MG. Effects of postoperative rehabilitation on limb function after cranial cruciate ligament repair in dogs. JAVMA 2002; 220(9):1325-1330.

23. Grewal R, Chan Saw SS, Vartimidus S, et al. Evaluation of passive and active rehabilitation and of tendon repair for partial tendon lacerations after three weeks of healing in canines. Clin Biomech 2006; 21(8):804-809.

24. Levine D, Rittenberry L, Millis DL. Aquatic therapy. In Millis D, Levine D, Taylor RA (eds): Canine Rehabilitation and Physical Therapy. Philadelphia: Saunders Elsevier, 2004, pp 264-276.

John M. Burnett is a fourth-year veterinary student at Mississippi State University College of Veterinary Medicine. He is interested in specializing in small animal surgery after completing his veterinary degree.

Jennifer L. Wardlaw, DVM, MS, Diplomate ACVS, is an assistant professor of small animal surgery in the Department of Clinical Sciences at Mississippi State University College of Veterinary Medicine. Her interests include arthritis, reconstructive surgery, wounds, nutraceuticals, and developmental orthopedic diseases. Dr. Wardlaw has spoken at numerous national meetings as well as published various research articles and book chapters. She received her DVM from University of Missouri and completed her internship, residency, and MS at Mississippi State University.

# data[].attributes.attachment_link.title
Physical Rehabilitation for Veterinary Practices

# data[].attributes.attachment_link.readable_text
Prescription diets targeted for pets with urinary conditions such as FLUTD (Feline Lower Urinary Tract Disease), idiopathic cystitis (regular bladder inflammation of no known cause), and urinary crystals or stones have specific mechanisms of action to dissolve urinary crystals and prevent urinary stones. When we give a pet two different brands of prescription food, it ends up reducing the effect of both diets and leaving the pet at risk for a recurrence of stones/crystals.

Royal Canin Urinary S/O works by diluting the urine to help drive struvites to stay in their dissolved states instead of combining in the urine into crystals or stones. Urinary S/O is high in sodium to signal the kidneys to excrete the extra sodium, which in turn causes the kidneys to excrete more water into the urine, leading to dilution. This action also signals the pet's brain to drink more. Working this way in the body, it helps maintain a low urine specific gravity (USG). Urinary S/O works best when given as canned food or with the animal encouraged to drink as much water as possible to aid in dilution. Other benefits of this diet include limiting the number of minerals that combine to make up stones and crystals, controlling the pH of the urine and working to both prevent and dissolve existing crystals/stones.

Hill's C/D also works to control the pH of the urine and the quantities of certain minerals that contribute to the production of struvites and calcium oxalates. Phosphorus and magnesium, for example, are controlled as they are the building block for struvites and calcium for calcium oxalates. It helps to maintain the urine pH to be between 6.2-6.4, which is acidic enough to dissolve struvites but also an ideal level to prevent oxalate formation.

Hill's C/D has added Omega-3s and antioxidants to reduce inflammation. Potassium citrate is also found in this diet to help bind excess calcium in the urine, which is how it helps prevent calcium from forming into calcium oxalates. It is why Hill's C/D is typically the brand recommended for calcium oxalates, as it is formulated for dissolution and prevention.

The Hill's diet S/D is a dissolution diet, which works to aggressively reduce struvites, keeping the pH level down to 5.9-6.1. It is not recommended as a long term diet as this causes the urine to be too acidic to prevent calcium oxalates. Often this will be prescribed to help aid in getting the pet cleared of struvites before putting them on a long term urinary diet such as the ones listed above.

Purina UR works similarly to Royal Canin, where it is designed to dilute the urine. The main difference between UR and Royal Canin is that UR has less sodium, more protein, and can be used for weight loss. It comes in a Savory Selects version (gravy and chunks) that has the highest protein, lowest carbs and lowest fat in a urinary diet on the market. Meaning that this diet is best for pets who are borderline overweight or are obese.

When you mix Royal Canin Urinary S/O or Purina UR with Hill's C/D, the overall concentration of sodium is decreased, which interferes with the dilution process. It also means there is an increase in phosphorus, calcium and magnesium (as these are not in the same amounts in RC and Purina that they are in the Hill's brand). The minerals that are the building blocks for the stones are not at the desired levels. Mixing the products does not allow for control of the urine's pH, meaning it is not at a specific level to counteract the development of future stones or crystals.

All scientific studies done on these diets have been performed with the pet eating solely the particular brand of the diet and at those times have been proven to work effectively. Due to this, to guarantee this effectiveness, we have to follow the same guidelines set during these studies, aka feed only the one brand diet. There has not yet been a study testing if there is the same or similar level of effectiveness when mixing. The safest option is to stick to a single brand or switch over entirely to another brand if the pet gets tired of or disinterested in the particular food being offered.

Written by: Tracey Westhaver, Reception Manager

# data[].attributes.attachment_link.title
Why You Cannot Mix Different Brands of Urinary Diets - Dartmouth Veterinary Hospital

# data[].attributes.attachment_link.description
Prescription diets targeted for pets with urinary conditions such as FLUTD (Feline Lower Urinary Tract Disease), idiopathic cystitis (regular bladder inflammation of no known cause), and urinary crystals or stones have specific mechanisms of action to dissolve urinary crystals and prevent urinary stones. When we give a pet two different brands of prescription food, it [...]