-LMWH

-Heparin inhibits coagulation of binding to inactive antihrombin III

-cause conformational change

-potentiate activity of antithrombin III

-active antithrombin III binds & inhibits factor xa

-lead to inhibition of conversion of prothrombin to thrombin

-inhibit conversion of fibrinogen to fibrin formation

-to prevent further clot formation in plasma

-inhibit vit K epoxide reductase component

-inhibit the reduction of vit K epoxide

-to active hydroquinone which subsequently inactive factor II, VII, IX, X

Must be avoided in people who have severe edema, leg deformities and peripheral arterial disease.

-high body mass index (BMI )

-need at least 150 minutes of aerobic activity a week

Eating food high in calories

-food high in sugar (lead to accumulation of fat in adipose tissue)

-food high in saturated fat (can lead to fat accumulation in blood vessels)

Not getting enough good-quality sleep

-affect hormones that control hunger urges

- make us overeat or not recognize our body’s signals that we are full.

High amounts of stress

-can affect the brain and trigger your body to make hormones,such as cortisol, that control energy balances and hunger urges.

-these hormones changes can make you eat more and store more fat

Health conditions

- metabolic syndrome and polycystic ovary syndrome cause people to gain weight

-genetic (researchers have found at least 15 genes that influence obesity. Studies show that genetics may play a more important role in people with obesity than in people who are overweight)

Medicines

-cause weight gain by distrusting the chemical signals that tell your brain you are hungry. These include:

• antidepressants

• Antipsychotics

• Beta-blockers

• Birth Control

• Glucocorticoids

• Insulin

Environment

-live, work, home, buildings in which you work or shop, streets and open spaces

-people living in neighbourhoods with more fast food restaurants are more likely to be overweight or obese

Causes and risk factors | NHLBI, NIH. (2022, March 24). NHLBI, NIH. https://www.nhlbi.nih.gov/health/overweight-and-obesity/causes

Symptoms:

i) distal edema

ii) cyanosis - when your skin, lips and/or nails turn a bluish tone due to lack of oxygen in your blood

iii) superficial vein dilation

iv) heat

v) tenderness

vi) redness

vii) swelling

iix) pain

What is Homan Sign?

A clinical finding of pain behind the knee upon forced dorsiflexion of the foot. It has been traditionally performed as part of the physical examination in individuals with suspected deep vein thrombosis (DVT) of the lower extremity. Flexion of the knee and forced dorsiflexion of the ankle causes traction on the posterior tibial vein, resulting in pain behind the knee.

What does a positive Homan Sign mean?

For many years, a positive Homan Sign was thought to be a clinical sign of deep vein thrombosis of the lower extremity, however, evidence shows that not all individuals with DVT exhibit a positive Homan sign at evaluation.

Hernandez A. (2025, Jan 07). Homan Sign. Osmosis from Elsevier.

https://www.osmosis.org/answers/homan-sign

https://www.goodrx.com/drugs/side-effects/these-7-medications-can-cause-puffy-legs-and-ankles#:~:text=6.-,Birth%20control%20pills,up%20in%20a%20similar%20way.

-decrease plasma colloid osmotic pressure

What causes a swelling / oedema?

1)heart failure

-heart fail to pump blood normally from vein into the artery

-raised venous & capillary pressure cause increase capillary filtration

2)decreased kidney excretion of salt & water

-most sodium chloride added to the blood remains in the extracellular compartment & only a small amount enters the cell

Guyton & hall textbook

Blood clotting : Toxic chemicals change platelets, making them sticky and prone to clumping and clotting, even when there is no injury. Nicotine also increases the number of platelets > more sticky platelets > clots develop at faster rate > amplifies effect of slow and thickened blood flow > increase the risk of DVT

https://www.memphisvein.com/blog/smoking-is-a-major-dvt-risk-factor-heres-what-you-should-know

Kumar, V., Abbas, A. K., & Aster, J. C. (2018). Robbins Basic Pathology (10th Edition). Elsevier Inc.

• decreased blood flow

• normally, muscle contraction helps pump venous blood back to the heart

• due to immobilization, milking action of the leg muscle is reduced

• resulting in stasis

Endothelial Dysfunction

• prolonged immobilization leads to local vessel wall injury

• due to pressure & hypoxia

• damaged endothelium can contributes to clot formation

https://pubmed.ncbi.nlm.nih.gov/15356668/

https://www.sciencedirect.com/science/article/pii/S1538783622151007?utm_source=chatgpt.com

A Wells score is calculated with patients scoring +1 point for each of the below criteria:

• active cancer (ongoing treatment/ treatment within last 6 months, or palliative)

• paralysis, paresis, or recent plaster immobilisation of the legs

• recently bedridden for ≥3 days, or major surgery within the last 12 weeks requiring general or local anaesthetics

• localised tenderness along the distribution of the deep venous system

• entire leg swelling

• calf swelling >3 cm compared with the asymptomatic leg (measured at 10 cm below the tibial tuberosity)

• pitting oedema (greater than on the asymptomatic leg)

• collateral superficial veins (non-varicose)

• previously documented DVT

Two points are subtracted if an alternative diagnosis is more likely than DVT (e.g. muscular tear, cellulitis, etc.).

DVT is considered likely in patients with a Wells score of 2 or above and unlikely in patients with a score of less than 2.