# data[].attributes.body
A minimally conscious state is characterized by some evidence of awareness of self and/or the environment, and patients tend to improve.

# data[].attributes.attachment_link.readable_text
NOTE: This is the Professional Version. CONSUMERS: Click here for the Consumer Version

Coma is unresponsiveness from which the patient cannot be aroused and in which the patient's eyes remain closed. Impaired consciousness refers to similar, less severe disturbances of consciousness; these disturbances are not considered coma. The mechanism for coma or impaired consciousness involves dysfunction of both cerebral hemispheres or of the reticular activating system (also known as the ascending arousal system). Causes may be structural or nonstructural (eg, toxic or metabolic disturbances). Damage may be focal or diffuse. Diagnosis is clinical; identification of cause requires laboratory tests and neuroimaging. Treatment is immediate stabilization and specific management of the cause. For long-term coma, adjunctive treatment includes passive range-of-motion exercises, enteral feedings, and measures to prevent pressure ulcers.

Decreased or impaired consciousness or alertness refers to decreased responsiveness to external stimuli. Severe impairment includes

Coma: The patient cannot be aroused, and the eyes are closed and do not open in response to any stimulation.

Stupor: The patient can be awakened only by vigorous physical stimulation.

Less severely impaired levels of consciousness are often labeled as lethargy or, if more severe, obtundation. However, differentiation between less severely impaired levels is often imprecise; the label is less important than a precise clinical description (eg, "the best level of response is partial limb withdrawal to nail bed pressure"). Delirium differs because cognitive disturbances (in attention, cognition, and level of consciousness) fluctuate more; also, delirium is usually reversible. Patients with delirium may have periods of appropriate attention and cognition alternating with periods of impaired attention and cognition.

Maintaining alertness requires intact function of the cerebral hemispheres and preservation of arousal mechanisms in the reticular activating system (RAS-also known as the ascending arousal system)-an extensive network of nuclei and interconnecting fibers in the upper pons, midbrain, and posterior diencephalon. Therefore, the mechanism of impaired consciousness must involve both cerebral hemispheres or dysfunction of the RAS.

To impair consciousness, cerebral dysfunction must be bilateral; unilateral cerebral hemisphere disorders are not sufficient, although they may cause severe neurologic deficits. However, rarely, a unilateral massive hemispheric focal lesion (eg, left middle cerebral artery stroke) impairs consciousness if the contralateral hemisphere is already compromised or if it results in compression of the contralateral hemisphere (eg, by causing edema).

Usually, RAS dysfunction results from a condition that has diffuse effects, such as toxic or metabolic disturbances (eg, hypoglycemia, hypoxia, uremia, drug overdose). RAS dysfunction can also be caused by focal ischemia (eg, certain upper brain stem infarcts), hemorrhage, or direct, mechanical disruption.

Any condition that increases intracranial pressure (ICP) may decrease cerebral perfusion pressure, resulting in secondary brain ischemia. Secondary brain ischemia may affect the RAS or both cerebral hemispheres, impairing consciousness.

In addition to the direct effects of increased ICP on neuronal and vascular cells, cellular pathways of apoptosis and autophagy (which are forms of programmed cell death or destruction) can become activated.

Impaired consciousness may progress to coma and ultimately to brain death.

Common Causes of Coma or Impaired Consciousness

Seizures (eg, nonconvulsive status epilepticus) or a postictal state caused by an epileptogenic focus

Psychiatric disorders (eg, psychogenic unresponsiveness) can mimic impaired consciousness, are volitional, and can be distinguished from true impaired consciousness by neurologic examination.

Symptoms and Signs

Consciousness is decreased to varying degrees. Repeated stimuli arouse patients only briefly or not at all.

Eye abnormalities: Pupils may be dilated, pinpoint, or unequal. One or both pupils may be fixed in midposition. Eye movement may be dysconjugate or absent (oculomotor paresis) or involve unusual patterns (eg, ocular bobbing, ocular dipping, opsoclonus). Homonymous hemianopia may be present. Other abnormalities include absence of blinking in response to visual threat (almost touching the eye), as well as loss of the oculocephalic reflex (the eyes do not move in response to head rotation), the oculovestibular reflex (the eyes do not move in response to caloric stimulation), and corneal reflexes.

Autonomic dysfunction: Patients may have abnormal breathing patterns (Cheyne-Stokes or Biot respirations), sometimes with hypertension and bradycardia (Cushing reflex). Abrupt respiratory and cardiac arrest may occur.

Motor dysfunction: Abnormalities include flaccidity, hemiparesis, asterixis, multifocal myoclonus, decorticate posturing (elbow flexion and shoulder adduction with leg extension), and decerebrate posturing (limb extension and internal shoulder rotation).

Other symptoms: If the brain stem is compromised, nausea, vomiting, meningismus, occipital headache, ataxia, and increasing somnolence can occur.

Impaired consciousness is diagnosed if repeated stimuli arouse patients only briefly or not at all. If stimulation triggers primitive reflex movements (eg, decerebrate or decorticate posturing), impaired consciousness may be deepening into coma.

Diagnosis and initial stabilization (airway, breathing, and circulation) should occur simultaneously. Temperature is measured to check for hypothermia or hyperthermia; if either is present, treatment is started immediately. Glucose levels must be measured at bedside to identify low levels, which should also be corrected immediately. If trauma is involved, the neck is immobilized until clinical history, physical examination, or imaging tests exclude an unstable injury and damage to the cervical spine.

Medical identification bracelets or the contents of a wallet or purse (eg, hospital identification card, drugs) may provide clues to the cause. Relatives, paramedics, police officers, and any witnesses should be questioned about the circumstances and environment in which the patient was found; containers that may have held food, alcohol, drugs, or poisons should be examined and saved for identification (eg, drug identification aided by a poison center) and possible chemical analysis.

Relatives should be asked about the following:

Medical records should be reviewed if available.

Physical examination should be focused and efficient and should include thorough examination of the head and face, skin, and extremities.

Signs of head trauma include periorbital ecchymosis (raccoon eyes), ecchymosis behind the ear (Battle sign), hemotympanum, instability of the maxilla, and cerebrospinal fluid (CSF) rhinorrhea and otorrhea. Scalp contusions and small bullet holes can be missed unless the head is carefully inspected.

If unstable injury and cervical spine damage have been excluded, passive neck flexion is done; stiffness suggests subarachnoid hemorrhage or meningitis.

Findings may suggest a cause:

The neurologic examination determines whether the brain stem is intact and where the lesion is located within the CNS. The examination focuses on the following:

Level of consciousness is evaluated by attempting to wake patients first with verbal commands, then with nonnoxious stimuli, and finally with noxious stimuli (eg, pressure to the supraorbital ridge, nail bed, or sternum).

The Glasgow Coma Scale (see table Glasgow Coma Scale) was developed to assess patients with head trauma. For head trauma, the score assigned by the scale is valuable prognostically. For coma or impaired consciousness of any cause, the scale is used because it is a relatively reliable, objective measure of the severity of unresponsiveness and can be used serially for monitoring. The scale assigns points based on responses to stimuli.

Eye opening, facial grimacing, and purposeful withdrawal of limbs from a noxious stimulus indicate that consciousness is not greatly impaired. Asymmetric motor responses to pain or deep tendon reflexes may indicate a focal hemispheric lesion.

Glasgow Coma Scale*

*Combined scores < 8 are typically regarded as coma.

Adapted from Teasdale G, Jennett B: Assessment of coma and impaired consciousness. A practical scale. Lancet 2:81-84; 1974.

As impaired consciousness deepens into coma, noxious stimuli may trigger stereotypic reflex posturing.

Decorticate posturing can occur in structural or metabolic disorders and indicates hemispheric damage with preservation of motor centers in the upper portion of the brain stem (eg, rubrospinal tract).

Decerebrate posturing indicates that the upper brain stem motor centers, which facilitate flexion, have been structurally damaged and that only the lower brain stem centers (eg, vestibulospinal tract, reticulospinal tract), which facilitate extension, are responding to sensory stimuli.

Decerebrate posturing may also occur, although less often, in diffuse disorders such as anoxic encephalopathy.

Flaccidity without movement indicates that the lower brain stem is not affecting movement, regardless of whether the spinal cord is damaged. It is the worst possible motor response.

Asterixis and multifocal myoclonus suggest metabolic disorders such as uremia, hepatic encephalopathy, hypoxic encephalopathy, and drug toxicity.

Psychogenic unresponsiveness can be differentiated because although voluntary motor response is typically absent, muscle tone and deep tendon reflexes remain normal, and all brain stem reflexes are preserved. Vital signs are usually not affected.

The following are evaluated:

Pupillary responses and extraocular movements provide information about brain stem function (see table Interpretation of Pupillary Response and Eye Movement). One or both pupils usually become fixed early in coma due to structural lesions, but pupillary responses are often preserved until very late when coma is due to diffuse metabolic disorders (called toxic-metabolic encephalopathy), although responses may be sluggish. If one pupil is dilated, other causes of anisocoria should be considered; they include past ocular trauma, certain headaches, and use of a scopolamine patch (if the drug comes in contact with the eyes).

Interpretation of Pupillary Response and Eye Movements

3rd cranial nerve compression (eg, in transtentorial herniation), usually due to an ipsilateral lesion (see Anisocoria)

Midbrain dysfunction due to structural damage (eg, infarction, hemorrhage)

Severe metabolic depression by drugs or toxins (all other brain stem reflexes are also absent)

Massive pontine hemorrhage

Toxicity due to opioids or certain insecticides (eg, organophosphates, carbamates)

Brain stem lesion on the opposite side

Cerebral hemisphere lesion on the same side

Further testing required (eg, oculocephalic and oculovestibular reflexes)

Possibly toxicity due to phenobarbital or phenytoin, Wernicke encephalopathy, botulism, or brain death

The fundi should be examined. Papilledema may indicate increased ICP but may take many hours to appear. Increased ICP can cause earlier changes in the fundi, such as loss of retinal venous pulsations, disk hypermia, dilated capillaries, blurring of the medial disk margins, and sometimes hemorrhages. Subhyaloid hemorrhage may indicate subarachnoid hemorrhage.

The oculocephalic reflex is tested by the doll's-eye maneuver in unresponsive patients: The eyes are observed while the head is passively rotated from side to side or flexed and extended. This maneuver should not be attempted if cervical spine instability is suspected.

If the patient is unconscious and the oculocephalic reflex is absent or the neck is immobilized, oculovestibular (cold caloric) testing is done. After integrity of the tympanic membrane is confirmed, the patient's head is elevated 30°, and with a syringe connected to a flexible catheter, the examiner irrigates the external auditory canal with 50 mL of ice water over a 30-second period.

The spontaneous respiratory rate and pattern should be documented unless emergency airway intervention is required. It may suggest a cause.

Initially, pulse oximetry, fingerstick plasma glucose measurements, and cardiac monitoring are done.

Blood tests should include a comprehensive metabolic panel (including at least serum electrolytes, blood urea nitrogen [BUN], creatinine, and calcium levels), complete blood count (CBC) with differential and platelets, liver function tests, and ammonia level.

Arterial blood gases (ABGs) are measured, and if carbon monoxide toxicity is suspected, carboxyhemoglobin level is measured.

Blood and urine should be obtained for culture and routine toxicology screening; serum ethanol level is also measured. Other toxicology screening panels and additional toxicology tests (eg, serum drug levels) are done based on clinical suspicion.

If the diagnosis remains uncertain, particularly if nonconvulsive status epilepticus (recurrent seizures without prominent motor symptoms) is being considered, EEG may be done. In most comatose patients, EEG shows slowing and reductions in wave amplitude that are nonspecific but often occur in toxic-metabolic encephalopathy. In some patients with nonconvulsive status epilepticus, the EEG shows spikes, sharp waves, or spike and slow complexes.

ECG (12-lead) is also done to check for myocardial infarction and new arrhythmias.

Chest x-ray should be done to check for new lung disease that may affect brain oxygenation.

If the cause is not immediately apparent, noncontrast head CT should be done as soon as possible to check for masses, hemorrhage, edema, evidence of bone trauma, and hydrocephalus. Initially, noncontrast CT rather than contrast CT is preferred to rule out brain hemorrhage. MRI can be done instead if immediately available, but it is not as quick as newer-generation CT scanners and may not be as sensitive for traumatic bone injuries (eg, skull fractures). Contrast CT can then be done if noncontrast CT is not diagnostic. MRI or contrast CT may detect isodense subdural hematomas, multiple metastases, sagittal sinus thrombosis, herpes encephalitis, or other causes missed by noncontrast CT.

If coma is unexplained after MRI or CT and other tests, lumbar puncture (spinal tap) is done to check opening pressure and to exclude infection, subarachnoid hemorrhage, and other abnormalities. However, MRI or CT images should also be reviewed for intracranial masses, obstructive hydrocephalus, and other abnormalities that could obstruct CSF flow or the ventricular system and thus significantly increase ICP. Such abnormalities contraindicate lumbar puncture. Suddenly lowering CSF pressure, as can occur during lumbar puncture, in patients with increased ICP could trigger brain herniation; however, this outcome is uncommon.

CSF analysis includes cell and differential counts, protein, glucose, Gram staining, cultures, and sometimes, based on clinical suspicion, specific tests (eg, cryptococcal antigen test, cytology, measurement of tumor markers, Venereal Disease Research Laboratory [VDRL] tests, polymerase chain reaction [PCR] for herpes simplex, visual or spectrophotometric determination of xanthochromia).

If increased ICP is suspected, CSF pressure is measured. Hyperventilation, managed by an intensive care unit (ICU) specialist, should be considered. Hyperventilation causes hypocapnia, which in turn decreases cerebral blood flow globally through vasoconstriction. Reduction in PCO2 from 40 mm Hg to 30 mm Hg can reduce ICP by about 30%. PCO2 should be maintained at 25 to 30 mm Hg, but aggressive hyperventilation to < 25 mm Hg should be avoided because this approach may reduce cerebral blood flow excessively and result in cerebral ischemia.

If diagnosis remains uncertain, EEG may be done. In most comatose patients, EEG shows slowing and reductions in wave amplitude that are nonspecific but often occur in toxic-metabolic encephalopathy. However, EEG monitoring (eg, in the ICU) is increasingly identifying nonconvulsive status epilepticus. In such cases, the EEG may show spikes, sharp waves, or spike and slow complexes.

Prognosis depends on the cause, duration, and depth of the impairment of consciousness. For example, absent brain stem reflexes indicates a poor prognosis after cardiac arrest, but not always after a sedative overdose. In general, if unresponsiveness lasts < 6 hours, prognosis is more favorable.

After coma, the following prognostic signs are considered favorable:

If the cause is a reversible condition (eg, sedative overdose, some metabolic disorders such as uremia), patients may lose all brain stem reflexes and all motor response and yet recover fully. After trauma, a Glasgow Coma Scale score of 3 to 5 may indicate fatal brain damage, especially if pupils are fixed or oculovestibular reflexes are absent.

After cardiac arrest, clinicians must exclude major confounders of coma, including sedatives, neuromuscular blockade, hypothermia, metabolic derangements, and severe liver or kidney failure. If brain stem reflexes are absent at day 1 or lost later, testing for brain death is indicated. Prognosis is poor if patients have any of the following:

If patients were treated with hypothermia, 72 hours should be added to the times above because hypothermia slows recovery. If any of the above criteria is met, outcome is usually (but not always) poor; thus, whether to withdraw life support may be a difficult decision.

Patients may also have other neurologic and nonneurologic complications, depending on the cause and duration of impaired consciousness. For example, a drug or disorder causing metabolic coma may also cause hypotension, arrhythmias, myocardial infarction, or pulmonary edema. Prolonged hospitalization in an ICU may also result in polyneuropathy, myopathy, and other complications (eg, pulmonary embolism, pressure ulcers, urinary tract infection).

Airway, breathing, and circulation must be ensured immediately. Hypotension must be corrected. Patients are admitted to the ICU so that respiratory and neurologic status can be monitored. If hypertension is present, blood pressure should be reduced carefully; lowering blood pressure below the patient's usual level can lead to brain ischemia.

Because some patients in coma are undernourished and susceptible to Wernicke encephalopathy, thiamin 100 mg IV or IM should be given routinely. If plasma glucose is low, patients should be given 50 mL of 50% dextrose IV, but only after they have been given thiamin.

If trauma is involved, the neck is immobilized until CT is done to rule out damage to the cervical spine.

If opioid overdose is suspected, naloxone 2 mg IV is given.

If a recent (within about 1 hour) drug overdose is possible, gastric lavage can be done through a large-bore orogastric tube (eg, ≥ 32 Fr) after endotracheal intubation. Activated charcoal can then be given as needed via the orogastric tube.

Coexisting disorders and abnormalities are treated as indicated. For example, metabolic abnormalities are corrected. Core body temperature may need to be corrected (eg, cooling for severe hyperthermia, warming for hypothermia).

Patients with any of the following require endotracheal intubation to prevent aspiration and ensure adequate ventilation:

If increased ICP is suspected, intubation should be done via rapid-sequence oral intubation (using a paralytic drug) rather than via nasotracheal intubation; nasotracheal intubation in a patient who is breathing spontaneously causes more coughing and gagging, thus increasing ICP, which is already increased because of intracranial abnormalities.

To minimize the increase in ICP that may occur when the airway is manipulated, some clinicians recommend giving lidocaine 1.5 mg/kg IV 1 to 2 minutes before giving the paralytic. Patients are sedated before the paralytic is given. Etomidate is a good choice in hypotensive or trauma patients because it has minimal effects on blood pressure; IV dose is 0.3 mg/kg for adults (or 20 mg for an average-sized adult) and 0.2 to 0.3 mg/kg for children. Alternatively, if hypotension is absent and unlikely and if propofol is readily available, propofol 0.2 to 1.5 mg/kg may be used.

Succinylcholine 1.5 mg/kg IV is typically used as a paralytic. Paralytics should be used only when they are deemed necessary for intubation and needed to avoid further increases in ICP. Otherwise, paralytics should be avoided because rarely, drugs such as succinylcholine can lead to malignant hyperthermia and can mask neurologic findings and changes.

Pulse oximetry and ABGs (if possible, end-tidal CO2) should be used to assess adequacy of oxygenation and ventilation.

If intracranial pressure (ICP) is increased, clinicians should monitor intracranial and cerebral perfusion pressure, and pressures should be controlled. The goal is to maintain ICP at ≤ 20 mm Hg and cerebral perfusion pressure at 50 to 70 mm Hg. Cerebral venous drainage can be enhanced (thus lowering ICP) by elevating the head of the bed to 30° and by keeping the patient's head in a midline position.

Control of increased ICP involves several strategies:

If ICP continues to increase despite other measures to control it, the following may be used:

Titrated hypothermia: When ICP is increased after head trauma or cardiac arrest, hypothermia in the range of 32 to 35° C has been used to reduce ICP to < 20 mm Hg. However, use of hypothermia to lower ICP is controversial; some evidence ( 1) suggests that this treatment may not effectively lower ICP in adults or children and may have adverse effects.

Pentobarbital coma: Pentobarbital can reduce cerebral blood flow and metabolic demands. However, its use is controversial because the effect on clinical outcome is not consistently beneficial, and treatment with pentobarbital can lead to complications (eg, hypotension). In some patients with refractory intracranial hypertension that does not respond to standard hypercapnia and hyperosmolar therapy, pentobarbital can improve functional outcome. Coma is induced by giving pentobarbital 10 mg/kg IV over 30 minutes, followed by 5 mg/kg/hour for 3 hours, then 1 mg/kg/hour. The dose may be adjusted to suppress bursts of EEG activity, which is continuously monitored. Hypotension is common and is managed by giving fluids and, if necessary, vasopressors. Other possible adverse effects include arrhythmias, myocardial depression, and impaired uptake or release of glutamate.

Decompressive craniotomy: Craniotomy with duraplasty can be done to provide room for brain swelling. This procedure can prevent deaths, but overall functional outcome may not improve much, and it may lead to complications such as hydrocephalus in some patients ( 2). It may be most useful for large cerebral infarcts with impending herniation, particularly in patients < 50 years.

Patients require meticulous long-term care. Stimulants, sedatives, and opioids should be avoided.

Enteral feeding is started with precautions to prevent aspiration (eg, elevation of the head of the bed); a percutaneous endoscopic jejunostomy tube is placed if necessary.

Early, vigilant attention to skin care, including checking for breakdown especially at pressure points, is required to prevent pressure ulcers. Patients require frequent turning and position changes to prevent pressure ulcers. Sometimes special air mattresses are necessary to manage pressure ulcers.

Topical ointments to prevent desiccation of the eyes are beneficial.

Passive range-of-motion exercises done by physical therapists and taping or dynamic flexion splitting of the extremities may prevent contractures. Initiating physical therapy early can improve functional outcome in patients with polyneuropathy and myopathy.

2. Su TM, Lan CM, Lee TH, et al: Risk factors for the development of posttraumatic hydrocephalus after unilateral decompressive craniectomy in patients with traumatic brain injury. J Clin Neurosci, 2019. pii: S0967-5868(18)31288-8. doi: 10.1016/j.jocn.2019.02.006. [Epub ahead of print]

Elderly patients may be more susceptible to coma, altered consciousness, and delirium because of many factors, including the following:

Relatively minor problems, such as dehydration and urinary tract infections, can alter consciousness in the elderly.

In elderly patients, mental status and communications skills may be compromised, making lethargy and obtundation harder to recognize.

Age-related decreases in cognitive reserve and neuroplasticity can impair recovery from brain injury.

Click here for Patient Education

NOTE: This is the Professional Version. CONSUMERS: Click here for the Consumer Version

# data[].attributes.attachment_link.title
Overview of Coma and Impaired Consciousness - Neurologic Disorders - MSD Manual Professional Edition

# data[].attributes.attachment_link.description
NOTE: This is the Professional Version. CONSUMERS: Click here for the Consumer Version Coma is unresponsiveness from which the patient cannot be aroused and in which the patient's eyes remain closed. Impaired consciousness refers to similar, less severe disturbances of consciousness; these disturbances are not considered coma.

# data[].attributes.attachment_link.readable_text
NOTE: This is the Professional Version. CONSUMERS: Click here for the Consumer Version

A vegetative state is absence of responsiveness and awareness due to overwhelming dysfunction of the cerebral hemispheres, with sufficient sparing of the diencephalon and brain stem to preserve autonomic and motor reflexes and sleep-wake cycles. Patients may have complex reflexes, including eye movements, yawning, and involuntary movements to noxious stimuli, but show no awareness of self or environment. A minimally conscious state, unlike a vegetative state, is characterized by some evidence of awareness of self and/or the environment, and patients tend to improve. Diagnosis is clinical. Treatment is mainly supportive. Prognosis for patients with persistent deficits is typically bleak.

The vegetative state is a chronic condition that preserves the ability to maintain blood pressure (BP), respiration, and cardiac function, but not cognitive function. Hypothalamic and medullary brain stem functions remain intact to support cardiorespiratory and autonomic functions and are sufficient for survival if medical and nursing care is adequate. The cortex is severely damaged (eliminating cognitive function), but the reticular activating system (RAS) remains functional (making wakefulness possible). Midbrain or pontine reflexes may or may not be present. Patients have no awareness of self and interact with the environment only via reflexes. Seizure activity may be present but not be clinically evident.

Traditionally, a vegetative state that lasts > 1 month is considered to be a persistent vegetative state. However, a diagnosis of persistent vegetative state does not imply permanent disability because in very rare cases (eg, after traumatic brain injury), patients can improve, reaching a minimally conscious state or a higher level of consciousness.

The most common causes are

However, any disorder that results in brain damage can cause a vegetative state. Typically, a vegetative state occurs because the function of the brain stem and diencephalon resumes after coma, but cortical function does not.

In the minimally conscious state, unlike the vegetative state, there is evidence that patients are aware of themselves and/or their environment. Patients also tend to improve (ie, gradually become more conscious), but improvement is limited. This state may be the first indication of brain damage or may follow a vegetative state as people recover some function. Patients can transition between the vegetative state and minimally conscious state, sometimes for years after the original brain damage.

Symptoms and Signs

Patients in a vegetative state show no evidence of awareness of self or environment and cannot interact with other people. Purposeful responses to external stimuli are absent, as are language comprehension and expression.

The following are present in patients in a vegetative state:

The spontaneous roving eye movements may be misinterpreted as volitional tracking and can be misinterpreted by family members as evidence of awareness.

Patients cannot react to visual threat and cannot follow commands. The limbs may move, but the only purposeful motor responses that occur are primitive (eg, grasping an object that contacts the hand). Pain usually elicits a motor response (typically decorticate or decerebrate posturing) but no purposeful avoidance. Patients have fecal and urinary incontinence. Cranial nerve and spinal reflexes are typically preserved.

Rarely, brain activity, detected by functional MRI or electroencephalography (EEG), indicates a response to questions and commands even though there is no behavioral response. The extent of patients' actual awareness is not yet known. In most patients who have such brain activity, the vegetative state resulted from traumatic brain injury, not hypoxic encephalopathy.

Fragments of meaningful interaction with the environment are preserved. Patients in a minimally conscious state may do the following:

A vegetative state is suggested by characteristic findings (eg, no purposeful activity or comprehension) plus signs of an intact reticular formation. Diagnosis is based on clinical criteria. However, neuroimaging is indicated to rule out treatable disorders.

The vegetative state must be distinguished from the minimally conscious state. Both states can be permanent or temporary, and the physical examination may not reliably distinguish one from the other. Sufficient observation is needed. If observation is too brief, evidence of awareness may be overlooked. Some patients with severe Parkinson disease are misdiagnosed as being in a vegetative state.

CT or MRI can differentiate an ischemic infarct, an intracerebral hemorrhage, and a mass lesion involving the cortex or the brain stem. Magnetic resonance angiography can be used to visualize the cerebral vasculature after exclusion of a cerebral hemorrhage. Diffusion-weighted MRI is becoming the preferred imaging modality for following ongoing ischemic changes in the brain.

Positron emission tomography (PET) and single-photon emission computed tomography (SPECT) can be used to assess cerebral function (rather than brain anatomy). If the diagnosis of persistent vegetative state is in doubt, PET or SPECT should be done.

EEG is useful in assessing cortical dysfunction and identifying occult seizure activity.

Prognosis varies somewhat by cause and duration of the vegetative state. Prognosis may be better if the cause is a reversible metabolic condition (eg, toxic encephalopathy) than if the cause is neuronal death due to extensive hypoxia and ischemia or another condition. Also, younger patients may recover more motor function than older patients but not more cognition, behavior, or speech.

Recovery from a vegetative state is unlikely after 1 month if brain damage is nontraumatic and after 12 months if brain damage is traumatic. Even if some recovery occurs after these intervals, most patients are severely disabled. Rarely, improvement occurs late; after 5 years, about 3% of patients recover the ability to communicate and comprehend, but even fewer can live independently; no patients regain normal function.

If a vegetative state persists, most patients die within 6 months of the original brain damage. The cause is usually pulmonary infection, urinary tract infection, or multiple organ failure, or death may be sudden and of unknown cause. For most of the rest, life expectancy is about 2 to 5 years; only about 25% of patients live > 5 years. A few patients live for decades.

Most patients tend to recover consciousness but to a limited extent depending on how long the minimally conscious state has lasted. The longer it has lasted, the less chance of patients recovering higher cortical function. Prognosis may be better if the cause is traumatic brain injury.

Rarely, patients regain clear but limited awareness after years of coma, called awakenings by the news media.

Supportive care is the mainstay of treatment for patients in a vegetative state or minimally conscious state; it should include the following:

Vegetative state has no specific treatment. Decisions about life-sustaining care should involve social services, the hospital ethics committee, and family members. Maintaining patients, especially those without advanced directives to guide decisions about terminating treatment, in a prolonged vegetative state raises ethical and other (eg, resource utilization) questions.

Most patients in a minimally conscious state do not respond to specific treatments. However, in some cases, treatment with zolpidem, apomorphine, or amantadine can lead to improvement in neurologic responsiveness for as long as the drug is continued.

NOTE: This is the Professional Version. CONSUMERS: Click here for the Consumer Version

# data[].attributes.attachment_link.title
Vegetative State and Minimally Conscious State - Neurologic Disorders - MSD Manual Professional Edition

# data[].attributes.attachment_link.description
NOTE: This is the Professional Version. CONSUMERS: Click here for the Consumer Version A vegetative state is absence of responsiveness and awareness due to overwhelming dysfunction of the cerebral hemispheres, with sufficient sparing of the diencephalon and brain stem to preserve autonomic and motor reflexes and sleep-wake cycles.

# data[].attributes.attachment_link.readable_text
Elaine Esposito (December 3, 1934 - November 25, 1978) held the record for longest coma according to Guinness World Records, having lost consciousness in 1941 and eventually dying in that condition more than 37 years later. Edwarda O'Bara and Aruna Shanbaug later exceeded Esposito's record of having been in the longest coma.

Elaine was the only child of Louis and Lucy Esposito of Chicago, Illinois. At age six she was taken to a hospital having suffered a ruptured appendix, where she underwent an appendectomy on August 6, 1941. She never awoke after being anesthetized. As the surgery was coming to an end, she went into convulsions, her temperature rose to 107.6 °F (42.0 °C), and doctors feared that she would not survive the night. The cause of the complication was debated with some suggesting that Elaine had encephalitis and others saying that her brain was not receiving enough oxygen during the operation.

The first ten months of her coma were spent in a Chicago hospital until her parents could no longer afford her care, at which point they took her home so her mother Lucy could care for her day and night. In her lengthy coma she showed states of both deep sleep and open-eyed unconsciousness and she grew slightly to 85 pounds (39 kg). Elaine survived numerous other conditions over the years, including additional abdominal surgery, pneumonia, the measles, and a collapsed lung. The family eventually moved to Tarpon Springs, Florida, and she was also taken to visit the Grotto at Lourdes, France, where her parents hoped for a miracle. Her father, Louis, who had been working multiple jobs, died from cancer in January 1978. Elaine died later that year at the age of 43 years 357 days, having been in a coma for 37 years 111 days.

Esposito's story was brought back into attention in the late 1990s and early 2000s in the controversy surrounding the case of Terri Schiavo, who was in a persistent vegetative state. Coincidentally, Schiavo and Esposito were both being cared for in Pinellas County, Florida, at the time of their deaths, and they also share a birthday (December 3).

# data[].attributes.attachment_link.description
Elaine Esposito (December 3, 1934 - November 25, 1978) held the record for longest coma according to Guinness World Records , having lost consciousness in 1941 and eventually dying in that condition more than 37 years later. Edwarda O'Bara and Aruna Shanbaug later exceeded Esposito's record of having been in the longest coma.

# data[].attributes.body
Jan Grzebski: 19-Year Coma and woke up.

# data[].attributes.attachment_link.readable_text
Coma is a period of prolonged unconsciousness, a coma can be caused by injury or physical illness - and in rare cases induced by doctors as a treatment option. Recovery is unpredictable and sometimes inexplicable. Seven years after a horrific car accident, South African Ayanda Nqinana finally awoke in early September, 2012. Ironically, the "miracle cure" for Nqinana was a sleeping pill similar to Ambien. Nqinana's story is proof that sometimes hope and patience prevail, as miraculous awakenings have been reported for patients in comas as long as 19 years.

Ayanda Nqinana: 7-Year Coma

Coma survivor Ayanda Nqinana's story is truly unique. His coma lasted seven years, from 2005 until 2012. As is the case with many other high-profile comas, Nqinana's was caused by a car accident. Unlike other comas revivals, his was sparked by a regimen of Stilnox, a sleeping pill similar to Ambien. Based on amateur research conducted by Nqinana's wife, Nomfundo, doctors agreed to treat Nqinana with Stilnox. After five days of treatment, Nqinana's seven-year coma was over. Nqinana is one example of a multi-year coma survivor, but he is not the only one to experience such an improbable recovery.

Terry Wallis: 19-Year Coma

Another car accident victim, Terry Wallis, suffered a brain injury that caused what turned out to be a record coma. In 1984, Wallis's pickup truck was thrown off a small bridge, in Stone County, Ark., killing another passenger. The accident left Wallis a quadriplegic, but amazingly, he was still alive upon arrival at a local hospital. After a few months, his coma had stabilized into a "minimally conscious state," but there was little reason to believe Wallis would survive and regain consciousness. Those odds looked increasingly grimmer with each passing year. Wallis's wife, Sandi, and new born daughter, Amber, were left to question if they would ever see Wallis "alive" again. Their questions were answered on June 11, 2003, as, incredibly, Wallis awoke from his 19-year coma - making him the survivor of the longest coma on record, matched, in years, by only one other person.
Photo Credit: Brian Chilson/AP Photo

Jan Grzebski: 19-Year Coma

The second 19-year coma survivor was a Polish man named Jan Grzebski. A railroad worker, Grzebski, 46, suffered his coma in 1988 in what was initially believed to be a workplace accident but was later attributed to a 5-centimeter brain tumor. Grzebski was able to survive the tumor, and eventually emerged from his coma in 2006. In an interview after he woke up, Grzebski admitted to being overwhelmed by the abundance of foods in his local shops, cell phones, and the fall of communism. Unfortunately, Grzebski passed away two years after waking up from his coma. The cause of death was a heart attack, believed to be related to the coma.
Photo Credit: AP Photo

Evel Knievel: 29 Days

Perhaps the most famous stuntman of all time, Knievel was known for punishing his body. One of his most memorable performances took place on New Year's Eve 1967. Knievel attempted to jump over the famous fountains at Caesars Palace in Las Vegas. He cleared the fountains but the landing failed, and he had a horrific crash in front of a national television audience. The crash resulted in a broken pelvis, fractured ribs, and a fractured skull. Knievel spent the next 29 days in a coma.
Photo Credit: Chris O'Meara/AP Photo

Rip Van Winkle (20-Year Coma) and Philip J. Fry (1,000-Year Coma)

These two characters might be works of fiction, but with our ever-expanding knowledge of comas, they might become the art that lives are imitating. Washington Irving's short story "Rip Van Winkle" tells the story of a colonial husband trying to skip out on his household chores. After enjoying some liquor, Rip falls into a deep sleep. When he regains consciousness, he realizes that his deep sleep was deeper than he could have possibly imagined: 20 years have passed, the American Revolution has ended, and another man with Rip's exact name is revealed to be his son.

The Rip Van Winkle tale inspired another coma-like story from Simpsons creator Matt Groening. Philip J. Fry, the main character of Groening's cartoon Futurama, is a pizza delivery boy who was cryonically frozen in the year 1999. The series begins with Fry being revived from his freeze-induced coma in the year 2999. Similar to Rip Van Winkle, Fry has a difficult time adjusting to his new era. The ultimate outcome of a forced coma through cryonics remains unknown, but that hasn't stopped approximately 250 people from trying to be the real-life Philip J. Fry: They've had themselves cryonically frozen and are patiently awaiting their awakenings.

# data[].attributes.attachment_link.title
Photo Gallery: Waking Up: Famous Coma Survivors

# data[].attributes.attachment_link.description
Coma is a period of prolonged unconsciousness, a coma can be caused by injury or physical illness - and in rare cases induced by doctors as a treatment option. Recovery is unpredictable and sometimes inexplicable. Seven years after a horrific car accident, South African Ayanda Nqinana finally awoke in early September, 2012.

# data[].attributes.body
For fun, as side notes.

# data[].attributes.body
The nature of an individuals responsiveness

# data[].attributes.body
POSSIBLY useful

# data[].attributes.attachment_link.readable_text
Abstract

In this paper I address three problems posed by modern medical technology regarding comatose dying patients. The first is that physicians sometimes hide behind the tests for whole-brain death rather than make the necessary human decision. The second is that the tests themselves betray a metaphysical judgment about death that may be ontologically faulty. The third is that discretion used by physicians and patients and/or family in deciding to cease treatment when the whole-brain death criteria may not be met are sometimes open to challenge. In each of these problems I find that the operative concept of death relates to life itself. This point is expanded by examining the uses of the word 'death' in our language and culture. From these I formulate an initial ontology of death. In it, death is described through a relationship with life, rather than as an absence of life, of consciousness, awareness, or sensation. This ontology then leads to a proposal for an ethics of discretion about the discontinuation of treatment for comatose patients.

Key words

Death Dying Coma Vegetative state Whole-brain death Ontology Philosophy Culture Ethics Medical ethics Ethics of discretion Ethics of rules Criteria for death Decision-making

This is a preview of subscription content, log in to check access.

# data[].attributes.attachment_link.title
The comatose patient, the ontology of death, and the decision to stop treatment

# data[].attributes.attachment_link.description
In this paper I address three problems posed by modern medical technology regarding comatose dying patients. The first is that physicians sometimes hide behind the tests for whole-brain death rather than make the necessary human decision. The second is that the tests themselves betray a metaphysical judgment about death that may be ontologically faulty.

# data[].attributes.body
Human beings are "rational animals"

# data[].attributes.body
"The essence of both the universe and man is the spirit."

# data[].attributes.body
“Unlike coma patients, vegetative state patients show a normal sleep–wake cycle, opening their eyes when awake and making roving eye movements.”

# data[].attributes.body
Affected with coma; unconscious. "Coma, (...) meaning deep sleep, is a state of extreme unresponsiveness, in which an individual exhibits novoluntary movement or behavior. Furthermore, in a deep coma, even painful stimuli (...) are unable to affect any response, and normal reflexes may be lost."

# data[].attributes.attachment_link.readable_text
Coma

Definition

Coma, from the Greek word "koma," meaning deep sleep, is a state of extreme unresponsiveness, in which an individual exhibits no voluntary movement or behavior. Furthermore, in a deep coma, even painful stimuli (actions which, when performed on a healthy individual, result in reactions) are unable to affect any response, and normal reflexes may be lost.

Description

Coma lies on a spectrum with other alterations in consciousness. The level of consciousness required by, for example, someone reading this passage lies at one extreme end of the spectrum, while complete brain death lies at the other end of the spectrum. In between are such states as obtundation, drowsiness, and stupor. All of these are conditions which, unlike coma, still allow the individual to respond to stimuli, although such a response may be brief and require stimulus of greater than normal intensity.

In order to understand the loss of function suffered by a comatose individual, it is necessary to first understand the important characteristics of the conscious state. Consciousness is defined by two fundamental elements: awareness and arousal.

Awareness allows one to receive and process all the information communicated by the five senses, and thus relate to oneself and to the outside world. Awareness has both psychological and physiological components. The psychological component is governed by an individual's mind and mental processes. The physiological component refers to the functioning of an individual's brain, and therefore that brain's physical and chemical condition. Awareness is regulated by cortical areas within the cerebral hemispheres, the outermost layer of the brain that separates humans from other animals by allowing for greater intellectual functioning.

Arousal is regulated solely by physiological functioning and consists of more primitive responsiveness to the world, as demonstrated by predictable reflex (involuntary) responses to stimuli. Arousal is maintained by the reticular activating system (RAS). This is not an anatomical area of the brain, but rather a network of structures (including the brainstem, the medulla, and the thalamus) and nerve pathways, which function together to produce and maintain arousal.

Causes and symptoms

Coma, then, is the result of something that interferes with the functioning of the cerebral cortex and/or the functioning of the structures which make up the RAS. In fact, a huge and varied number of conditions can result in coma. A good way of categorizing these conditions is to consider the anatomic and the metabolic causes of coma. Anatomic causes of coma are those conditions that disrupt the normal physical architecture of the brain structures responsible for consciousness, either at the level of the cerebal cortex or the brainstem, while metabolic causes of coma consist of those conditions that change the chemical environment of the brain, thereby adversely affecting function.

There are many metabolic causes of coma, including:

A decrease in the delivery to the brain of substances necessary for appropriate brain functioning, such as oxygen, glucose (sugar), and sodium.

The presence of certain substances that disrupt the functioning of neurons. Drugs or alcohol in toxic quantities can result in neuronal dysfunction, as can substances normally found in the body, but that, due to some diseased state, accumulate at toxic levels. Accumulated substances that might cause coma include ammonia due to liver disease, ketones due to uncontrolled diabetes, or carbon dioxide due to a severe asthma attack.

The changes in chemical levels in the brain due to the electrical derangements caused by seizures.

Diagnosis

As in any neurologic condition, history and examination form the cornerstone of diagnosis when the patient is in a coma; however, history must be obtained from family, friends, or EMS. The Glasgow Coma Scale is a system of examining a comatose patient. It is helpful for evaluating the depth of the coma, tracking the patient's progress, and predicting (somewhat) the ultimate outcome of the coma. The Glasgow Coma Scale assigns a different number of points for exam results in three different categories: opening the eyes, verbal response (using words or voice to respond), and motor response (moving a part of the body). Fifteen is the largest possible number of total points, indicating the highest level of functioning. The highest level of functioning would be demonstrated by an individual who spontaneously opens his/her eyes, gives appropriate answers to questions about his/her situation, and can carry out a command (such as "move your leg" or "nod your head"). Three is the least possible number of total points and would be given to a patient for whom not even a painful stimulus is sufficient to provoke a response. In the middle are those patients who may be able to respond, but who require an intense or painful stimulus, and whose response may demonstrate some degree of brain malfunctioning (such as a person whose only response to pain in a limb is to bend that limb in toward the body). When performed as part of the admission examination, a Glasgow score of three to five points often suggests that the patient has likely suffered fatal brain damage, while eight or more points indicates that the patient's chances for recovery are good. Expansion of the pupils and respiratory pattern are also important. Metabolic causes of coma are diagnosed from blood work and urinalysis to evaluate blood chemistry, drug screen, and blood cell abnormalities that may indicate infection. Anatomic causes of coma are diagnosed from CT (computed tomography) or MRI ( magnetic resonance imaging) scans.

Treatment

Coma is a medical emergency, and attention must first be directed to maintaining the patient's respiration and circulation, using intubation aand ventilation, administration of intravenous fluids or blood as needed, and other supportive care. If head trama has not been excluded, the neck should be stablized in the event of fracture. It is obviously extremely important for a physician to determine quickly the cause of a coma, so that potentially reversible conditions are treated immediately. For example, an infection may be treated with antibiotics; a brain tumor may be removed; and brain swelling from an injury can be reduced with certain medications. Various metabolic disorders can be addressed by supplying the individual

with the correct amount of oxygen, glucose, or sodium; by treating the underlying disease in liver disease, asthma, or diabetes; and by halting seizures with medication. Because of their low incidence of side effects and potential for prompt reversal of coma in certain conditions, glucose, the B-vitamin thiamine, and Narcan (to counteract any narcotic-type drugs) are routinely given.

Prognosis

Some conditions that cause coma can be completely reversed, restoring the individual to his or her original level of functioning. However, if areas of the brain have been sufficiently damaged due to the severity or duration of the condition which led to the coma, the individual may recover from the coma with permanent disabilities, or may even never regain consciousness. Take, for example, the situation of someone whose coma was caused by brain injury in a car accident. Such an injury can result in one of three outcomes. In the event of a less severe brain injury, with minimal swelling, an individual may indeed recover consciousness and regain all of his or her original abilities. In the event of a more severe brain injury, with swelling that resulted in further pressure on areas of the brain, an individual may regain consciousness, but may have some degree of impairment. The impairment may be physical (such as paralysis of a leg) or may even result in a change in the individual's intellectual functioning and/or personality. The most severe types of brain injury, short of death, result in states in which the individual loses all ability to function and remains deeply unresponsive. An individual who has suffered such a severe brain injury may remain in a coma indefinitely. This condition is termed persistent vegetative state.

Outcome from a coma is therefore quite variable and depends a great deal on the cause and duration of the coma. In the case of drug poisonings, extremely high rates of recovery can be expected following prompt medical attention. Patients who have suffered head injuries tend to do better than do patients whose coma was caused by other types of medical illnesses. Leaving out those people whose coma followed drug poisoning, only about 15% of patients who remain in a coma for more than just a few hours make a good recovery. Those adult patients who remain in a coma for greater than four weeks have almost no chance of eventually regaining their previous level of functioning. On the other hand, children and young adults have regained functioning even after two months in a coma.

Resources

Organizations

American Academy of Neurology. 1080 Montreal Ave., St. Paul, MN 55116. (612) 695-1940. http://www.aan.com.

Coma Recovery Association, Inc. 570 Elmont Rd., Suite 104, Elmont, NY 11003. (516) 355-0951.

Key terms

Anatomic - Related to the physical structure of an organ or organism.

Metabolic - Refers to the chemical processes of an organ or organism.

Neuron - The cells within the body which make up the nervous system, specifically those along which information travels.

Physiological - Pertaining to the functioning of an organ, as governed by the interactions between its physical and chemical conditions.

Psychological - Pertaining to the mind, its mental processes, and its emotional makeup.

Stimulus/stimuli - Action or actions performed on an individual which predictably provoke(s) a reaction.

coma
[ko´mah]

a state of unconsciousness from which the patient cannot be aroused, even by powerful stimuli. Traumatic brain injuries are the most frequent cause; other causes include severe uncontrolled diabetes mellitus, liver disease, kidney disease, and neurologic conditions. Evaluation of a patient in a coma is comprehensive. The underlying cause should be identified so that appropriate treatment can be initiated. magnetic resonance imaging, electroencephalography, and brainstem auditory evoked potentials give information about electrical activity of the brain in a patient who is comatose, although the results are not predictive of recovery. Some patients are able to emerge from a coma. In others, the coma may progress to a persistent vegetative state in which the functions of the brainstem and circulation remain relatively intact or may be supported with assistive technologies. Patients in irreversible coma may meet the criteria of brain death.

Patient Care. Assessment of the patient in a coma includes an evaluation of vital signs, determination of level of consciousness, neuromuscular responses, and reaction of the pupils to light. In most hospitals a standard form is used to measure and record the patient's responses to stimuli in objective terms. The glasgow coma scale is a standardized tool that aids in assessing a comatose patient and eliminates the use of ambiguous and easily misinterpreted terms such as unconscious and semicomatose. Additional assessment data are gathered relating to the underlying cause and the patient's immobility; these include evaluation of the gag and corneal reflexes. In the absence of gag reflex, regurgitation and aspiration are potential problems.

Abnormal rigidity and posturing in response to noxious stimuli are motor responses to coma. Decorticate rigidity is abnormal flexor posturing, with the arms, wrists, and fingers drawn up. The legs may be extended with plantar flexion. This type of rigidity usually indicates a lesion in the cerebral hemispheres or a disruption of the corticospinal tracts. Decerebrate rigidity is abnormal extensor posturing: in response to painful stimuli the extremities extend rigidly and the palms turn outward. This type of rigidity is indicative of damage to the brainstem and as a rule is a sign of greater cerebral impairment than is decorticate rigidity.

Comatose patients are predisposed to all the hazards of immobility, including impairment of skin integrity and development of pressure ulcers and contractures. A multidisciplinary, coordinated plan of care is essential. Families should be encouraged to be actively involved in care of the patient. The health care team should also recognize the family's need for support; the emotional and financial impacts of coma are usually significant.

alcoholic coma coma accompanying severe alcoholic intoxication.

alpha coma coma in which there are electroencephalographic findings of dominant alpha-wave activity.

hepatic coma coma accompanying cerebral damage resulting from degeneration of liver cells, especially that associated with cirrhosis of the liver.

myxedema coma an often fatal complication of long-term hypothyroidism in which the patient is comatose with hypothermia, depression of respiration, bradycardia, and hypotension; usually seen in elderly patients during cold weather.

co·ma
(kō'mă),

1. A state of profound unconsciousness from which one cannot be roused; may be due to the action of an ingested toxic substance or of one formed in the body, to trauma, or to disease.

2. An aberration of spheric lenses; occurring in cases of oblique incidence (for example, the image of a point becomes comet shaped).

coma
(kō′mə)

n. pl. co·mas

A state of deep, often prolonged unconsciousness, usually the result of injury, disease, or poison, in which an individual is incapable of sensing or responding to external stimuli and internal needs.

(1) COMA

Combining Monteplase with Angioplasty. A trial comparing direct PTCA to PTCA + prior mutant t-PA-monteplase in patients with acute MI
Conclusion Angiographic restenosis rates were significantly lower with monteplase in this very small study

(2) Coma

A state of unarousable unconsciousness; a sleep-like state
Aetiology Head injury, neurologic disease, acute hydrocephaly, intoxication or metabolic derangement or hypoglycemia

coma
Neurology A state of unarousable unconsciousness; a sleep-like state; not conscious Etiology Head injury, neurologic disease, acute hydrocephaly, intoxication or metabolic derangement or hypoglycemia. See Barbiturate coma, Diabetic coma, Induced pentobarbital coma, Pseudocoma.

co·ma
(kō'mă)

1. A state of profound unconsciousness from which one cannot be roused; may result from trauma, disease, or the action of an ingested toxic substance or of one formed in the body. [G. kōma, deep sleep]

2. An aberration of spheric lenses; occurring in cases of oblique incidence (e.g., the image of a point becomes comet-shaped). [G. komē, hair]

[G. kōma, deep sleep, trance]

coma A state of deep unconsciousness from which the affected person cannot be aroused even by strong stimulation. Coma can result from head injury, oxygen lack, interruption of the blood supply to the brain, poisoning and various disease states such as those occurring in uncontrolled diabetes, liver failure and kidney failure.

coma a tuft of hairs attached to the testa of a seed and used in wind dispersal.

coma

Monochromatic aberration of an optical system produced when the incident light beam makes an angle with the optical axis. The image appears like a comet with the tail pointing towards the axis. See aplanatic lens; sine condition.

co·ma
(kō'mă)

Profound unconsciousness from which one cannot be roused; may be due to the action of an ingested toxic substance or of one formed in the body, to trauma, or to disease.

[G. kōma, deep sleep, trance]

# data[].attributes.attachment_link.description
Coma, from the Greek word "koma," meaning deep sleep, is a state of extreme unresponsiveness, in which an individual exhibits no voluntary movement or behavior. Furthermore, in a deep coma, even painful stimuli (actions which, when performed on a healthy individual, result in reactions) are unable to affect any response, and normal reflexes may be lost.

# data[].attributes.body
Sigmund Freud, The Ego and the Id

# data[].attributes.body
arguments in favour/ arguments against

# data[].attributes.body
Like an average human

# data[].attributes.body
Comprehension

# data[].attributes.body
going under general anesthesia

# data[].attributes.body
What is consciousness?

# data[].attributes.body
Are people considered human/ not considered human in all different types of comatose state?

# data[].attributes.body
It's against human nature to cause suffering.
Is keeping people in a PVS against human nature?
Is being in a PVS against human nature?
Is it against our morals to allow this?

# data[].attributes.body
"82% of respondents prefer death"

# data[].attributes.body
Neurotypical humans believing you survive death.

# data[].attributes.body
What do we define as a comatose state?

# data[].attributes.body
US vs German study. Cultural differences.

# data[].attributes.attachment_link.readable_text
Inga Steppacher

Johanna Kissler

Research article

Keywords

Mind perception Morality End of life decisions Dualism Disorders of consciousness

Abbreviations

DOC

Disorders of consciousness

TBI

Traumatic brain injury

UWS

Unresponsive wakefulness syndrome

VS

Vegetative state

Electronic supplementary material

The online version of this article ( https://doi.org/10.1186/s40359-018-0217-4 ) contains supplementary material, which is available to authorized users.

Background

'How shall we regard those in [permanent vegetative state]? They are periodically awake, and their bodies breathe and digest on their own. These traits bespeak life. Yet they are not conscious and never will be: subjectively, this is death' [ 1] (p. 41).

Medical progress has provided the public with a clinical picture that seems to blur the line between life and death. Patients with the unresponsive wakefulness syndrome (UWS; [ 2]; former vegetative state, VS; [ 3, 4] are defined to have no self-awareness or conscious perception of their surroundings. Since the body is undoubtedly alive, whether or not the 'person' him- or herself still is seems hard to determine. Even relatives close to the patients can get confused about this issue. Holland et al., for example, report interviews with relatives of long-term UWS patients, showing that some relatives literally state that a patient is dead and alive in quick succession. For example, they quote 'Brian', a brother of a UWS patient with: 'He's already dead. The only reason he's not dead is because his heart pumps [...]' [ 5] (p. 417).

In this study, Gray and colleagues conducted a series of experiments to determine how much mind is ascribed to a UWS patient in comparison to either a healthy person or a deceased individual (experiment 1, n = 201). They also tested for religious beliefs as a variable potentially influencing mind ascription in their participants (experiment 2, n = 143). In a third experiment ( n  = 55), participants were asked to imagine to either die or fall into UWS themselves and were asked to rate how bad each of these outcomes would be for them and their families. Consistently, participants rated UWS patients to have less mind than the deceased. Religiosity and implicit dualism (the belief, that matter and spirit are separate from one another, irrespective of religiosity) were found to influence mind ascription in that religious persons and those holding implicit dualism, ascribed more mind to the dead. In general, participants rated UWS to be a state worse than death, both, for themselves and for their families.

Here, we aim to replicate and extend the series of studies reported by Gray et al., with a large German sample. So far, no published replication of Gray et al. exists, precluding strong claims about the generality of the findings. However, although USA and Germany, as Western cultures, are similar in many ways, there are also substantial differences that might influence the perception of UWS itself as well as the perceived tragedy of the resulting situation. According to Hofstede [ 32, 33], there are mainly six dimensions that can be used to characterize different cultures (see Additional file 1: Table S1). In particular, the scales of 'individualism - collectivism' and 'avoidance of uncertainty', reveal substantial differences between Germany and the US. The USA scores highest among 76 countries on individualism and the society is quite tolerant against uncertainties (rank 64 of 76 countries). US Americans value the self determined 'I' and the right and ability to live a self determined life. Autonomy and self-actualization are ultimate goals and freedom an individualist's ideal [ 33]. Americans value leisure time and the fulfillment of desires, 'now' over 'then', and are, in general, not too concerned about the future [ 32]. Therefore, UWS could be considered the exact opposite of the life values of US Americans.

For Germans, living in a more moderately individualist culture and being very avoidant of uncertainty, the situation could be different: UWS, although undoubtedly tragic, may interfere a little less with cultural values (since for example personal freedom and autonomy of the self are not valued as highly as in the USA). Furthermore, because they have little tolerance for uncertainties, Germans tend to think through most possibilities of 'what could happen' in life and have insurances for all eventualities [ 34]. German obligatory health insurance indeed covers the unlikely event of UWS. There is also a special "care allowance" ('Pflegegeld') that is paid to care-giving family members as well as access to highly professional care institutions or outpatient care services to disburden families ('Bundesministerium für Gesundheit': http://www.pflegestaerkungsgesetz.de / 11.04.2017). Ironically, for Germans, 'having things thought through' and feeling prepared could, in the unlikely event of having to care for a UWS patient or becoming one oneself, help to reduce the perceived tragedy of the UWS situation. Therefore, UWS could be regarded as more aversive in the USA than in Germany.

According to Hofstede [ 32, 33], short-term oriented cultures like the USA are also characterized by the belief that matter and spirit/mind are separated. Thus, members of such cultures should hold both explicit religious beliefs and implicit dualism. Long-term oriented cultures like Germany, on the other hand, in general, believe that matter and mind are integrated (which still allows for explicit religiosity but reduces implicit dualism). Indeed, Gray et al. [ 9] clearly demonstrated a separation in the perception of mind and matter (ascribing mental abilities to the deceased and none to the UWS patient) for their US sample. According to the above reasoning, Germans may generally ascribe more mind to UWS patients, since a living body is less likely seen without mind.

Besides general cultural factors, experience with UWS might also affect mind ascriptions.

Therefore, we asked all participants whether or not they personally know a UWS patient to assess the influence of familiarity with the syndrome since our own clinical experience as well as some studies [ 35] have shown, that some caregivers hold hopes for their patients that are not always shared by the medical staff.

Therefore, we explicitly included medical staff into the survey who should have expert knowledge in the area and whom we expected to have had, on average, exposure to both, UWS patients and deceased. The perception of UWS patients by medical doctors is of special importance since they are often involved in end of life decisions. In fact, it has been shown that up to 70% of all deaths on the examined critical care units occur due to discontinued life support which was recommended by doctors due to an 'unfavorable prognosis' (which usually includes a UWS prognosis) [ 36, 37]. Whether or not they ascribe mind to the patients and whether or not they perceive UWS 'as a faith worse than death' [ 38] is therefore likely to influence the advice and guidance they offer the families of patients [ 27].

Finally, since little is known about the factors influencing UWS perception even within a society, we assessed the potential influence of general demographic and socio-economic variables on mind ascription to UWS patients as an exploratory analysis.

In sum, we expect our German sample to ascribe more mind to the UWS patients and rate the condition of being in UWS as less tragic than the US sample did. We further expect the religious Germans to ascribe more mind to the deceased than the irreligious participants, but we expect no effect of implicit dualism within the German sample. Lastly, we explore the effects of personal knowledge and medical expertise as well as demographic variables on mind ascription to UWS patients.

Methods

We included all three experiments of Gray et al. [ 9] into a large on-line survey. Therefore, we translated the stories of David, who, after a car accident, was either alive (story 1), in UWS (story 2) or dead (story 3 and 4; the latter with a focus on the dead body in the morgue, referred to as the 'corpse-condition'). The names of American cities were replaced with German ones, otherwise, no changes were made (for both, English and translated story-vignettes please see Additional file 2: Text S1 and Additional file 3: Text S2).

Online-setting

Unlike Gray and colleagues, who ran their experiments 1 and 2 as paper and pencil versions and only experiment 3 on-line, here, all stories and questions were presented as an online survey. One of the four David-scenarios (life condition, UWS condition, death condition and corpse condition) were randomly assigned to each participant. After reading the short story, participants were asked to rate, on a response-scale from 1 (strongly disagree) to 7 (strongly agree), the mental abilities of David according to five statements ('David can influence the outcome of situations', 'David knows right from wrong', 'he remembers the events of his life', 'has emotions and feelings', 'is aware of his environment' and 'has a personality').

After completing this part, all participants were asked to imagine that they themselves would be involved in a car accident and would either die or become a long lasting UWS patient. They were then asked to rate on a scale from 1 (not bad at all) to 7 (extremely bad) how bad the respective outcome would be for a) themselves and b) for their families. To ensure that envisaged financial consequences of long time care or burial did not influence the rating, participants were told that all ensuing costs were covered by insurance. After that, as a manipulation check, participants were asked to state what happened to David in the story they read. The correct responses for the life-condition ('alive'), for the UWS-condition ('alive, with severe brain damage'), and for both dead-conditions ('deceased') had to be indicated. Participants who failed to answer correctly were later excluded from the analysis.

The manipulation check was followed by three questions about religiosity and how strongly they believe in life after death. Participants were also asked which religion they belong to. Then, participants answered some demographic questions regarding age, gender, and workplace. Finally, we asked three additional questions: "How much do you think you know about UWS?", "I have a UWS patient within my circle of acquaintances?" And: "I have/had contact to a patient in UWS?" For question one answers ranged from: 1 (nothing at all) to 7 (very much); Question two and three were yes or no questions. To complete the whole survey, participants needed about 5 to 10 min.

Participants

German participants were recruited from the University of Bielefeld, personal connections, via Link-posting on Facebook and Flyers in six different clinics within the area of Bielefeld, Paderborn and Bad Salzuflen, state of North Rhine-Westphalia. To test for cultural differences it is important to recruit representative samples of participants. Unfortunately, little information is given about Gray's US sample. It is stated that the sample was recruited randomly from college and metro areas in New England, Amtrak stations and New York City parks for the paper and pencil tests (experiment 1, n = 201; experiment 2, n = 143) and from the on-line platform MTurk to take part in the online survey (experiment 3; n  = 55).

In our study a total of 991 participants finished the questionnaire. Nine participants had to be excluded for being underaged, 72 participants had to be excluded because they failed the manipulation check and therefore seemed to be unable to remember what had happened to David in their story. This leaves 910 datasets for further analysis. Demographics can been seen in Table 1.

Results

Some of the data violated the sphericity requirement (Levene-test). However, non-parametric testing which was also performed only leads to numerical but not qualitative changes. Therefore, in the following, we report parametric tests, to facilitate direct comparison with the original study.

Table 2 shows results of the random assignment of the four vignette conditions to the participants.

Mind perception

As in Gray et al., a 'mind-perception-index' was formed by averaging the six mind perception questions. These indices of all four vignettes were submitted to an analysis of variance (ANOVA) which showed a significant effect for condition F(3, 909) = 204.34; p < .001. As Gray et al., we used Fisher's least significant difference (LSD) post hoc test, which showed that the life condition differs significantly from every other condition ( p < .001). There are also significant differences between the corpse condition and the death condition ( p = .005) as well as between corpse and UWS ( p < .001). UWS and Death conditions do not differ from each other. However, although mean values do not vary much, as evident from the histogram plot, there are substantially fewer participants completely denying mental life to the UWS patients than for both death groups (see Fig. 1).

Like Gray et al., we also analyzed the individual items. It was confirmed that participants in the life condition ascribe the most mental capabilities on every item ( p < 0.001). But unlike in the study of Gray and colleagues, UWS-David compared to the David in both death conditions was ascribed significantly more personality and is perceived as possessing more emotions and feelings (see Fig. 2).

Mean mind ascription: present data versus Gray et al

To compare Germany with the USA, the USA means and standard-deviations were extracted from Gray et al. and transformed to the same scale (from 1 to 7). There is no significant difference between either the life conditions assessment of the American participants ( n = 67, M = 5.77, SD = 1.76) and the German ones ( n = 257, M = 5.83, SD = 0.95) or for the death condition in the USA ( n = 67, M = 3.71, SD = 1.76) versus Germany ( n = 206, M = 3.23, SD = 1.80). There is, however, a highly significant difference between the ascription of mind for the UWS condition in the USA ( n = 67, M = 2.27, SD = 1.36) and Germany ( n = 223, M = 3.42, SD = 1.25), t(288) = 6.47, p < 0.001 (see also Fig. 3), with US participants ascribing less mind to the UWS patient than Germans do. There is also an overall difference between the death and UWS condition occurring only within the US sample. Due to the fact that mean and standard deviation for the corpse condition were not reported in the US study, a cross-cultural comparison between these two conditions could not be calculated.

Religiosity

Following Gray et al., we averaged the religiosity items to form a religiosity index. We then split all participants into thirds according to their scores on this index and compared those who scored at the top and the bottom third of the scale (tertiary split, [ 39]). This results in n = 211 (23%) participants with a low religiosity score and n = 298 (33%) with a high score. Four hundred one participants with medium religiosity scores were excluded from this analysis. We examined differences on the mind perception index in a 4 (dead, corpse, UWS, life) × 2 (religiosity high/low) ANOVA. There were significant main effects for condition F(3, 501) = 123.53, p < 0.001, ɳ ² = 0.43; for religiosity F(1, 501) = 35.90, p < 0.001, ɳ ² = 0.07 (with religious participants ascribing more mind in general) as well as a small but still highly significant interaction between the two factors F(3, 501) = 5.67, p = 0.001, ɳ ² = 0.03, essentially resulting from the fact that a group difference occurred in all conditions except the life condition (see Fig. 4).

Within both groups, mind perception scores are higher in the Life than in all other conditions p  < 0.001. Corpse, Death and UWS conditions do not differ within either group.

Between groups, the corpse conditions differ significantly ( p < 0.001), as does the death ( p < 0.001) and the UWS condition ( p  = 0.026). In each case, religious participants gave, on average, higher scores than non-religious ones. There is no between-group difference for the life condition.

Severity of outcome: present data versus Gray et al

To compare the severity of outcome as perceived by US and German participants we used the mean values of the death scale as a reference. We then calculated the difference for both groups of how much worse or how much better than death, UWS was perceived. This revealed the fact, that, on average, US participants perceived UWS as 1.52 points (on a 7 point scale) worse than death. Germans feel, on average, that UWS is 0.39 points worse than death. The independent samples t-test showed that both groups vary highly significant in the perceived severity of the situation t(223) = 3.18; p = 0.002. We used the same difference measure for when participants considered how bad this outcome would be for their families. Here, US participants rated to become a UWS patient to be 1.04 points worse for their families than an early death. Germans rated becoming a UWS patient as 0.01 points better than an early death. Again, the difference between both ratings is highly significant t (223) = 5.22; p  < 0.001.

Additionally, in the German sample, we found a significant correlation (r(223) = .25, p  < 0.001) between the mind perception score and the evaluation of the badness of the situation. It has, however, the opposite direction than in Gray et al. where less mind was ascribed, the worse the condition is viewed. Here we found, that the more mind is ascribed, the worse the condition is viewed.

Subjective knowledge and exposure to UWS patients

Correlations within the UWS vignette revealed no correlation between either subjective knowledge about UWS and mind ascription (r(218) = −.06, p = 0.422) or real world experience with UWS patients and mind ascription (point-bi-serial correlation for 'I have a UWS patient within my circle of acquaintances' (Yes/No): (r(218) = − 10, p = 0.138) and for I have/had contact to a UWS patient: (r(218) = −.06, p  = 0.394)).

Medical background

Since we were especially interested in the perception by medical staff of UWS patients and the dead, we compared the mind ascription of participants with a medical background and other participants specifically within the UWS and Death condition. For better comparability and in an attempt to exclude other factors like general life experience, work situation and family status, for this comparison we excluded all students and trainees from both groups. Independent samples t-Test within the UWS vignette reveals a significant difference between participants with a medical background ( n = 54, M = 3.53, SD = 1.30) and other employed participants without a medical background ( n = 94, M = 3.07, SD = 1.17), (t(158) = − 2.65, p = 0.03), participants with medical background ascribing more mental capabilities to UWS patients. For the death vignette there is no such difference (medical background: n = 36, M = 2.84, SD = 1.78; no medical background: n = 96, M = 3.21, SD = 1.83) t(130) = − 1.04, p = 0.30 (see also Fig. 5).

To further analyze the effect of medical expertise for perception of UWS, an additional sample of medical professionals was collected. Since the 54 medical professionals originally assigned to the UWS condition do not allow for further separations of professions, we additionally recruited further medical professionals in a second recruitment at the Kliniken Schmieder, Allensbach, Germany. Because these participants where added posthoc, they were not included into any analysis other than this one. This resulted in n = 71 medical professionals for this analysis in the PVS condition. Seven participants had to be excluded due to the fact that the profession was too rare (for example midwife or pharmacist) for further analysis. One person had to be excluded because he stated to work in the medical field but failed to identify his profession. Further descriptive characteristics are detailed in Table 3. One-way ANOVA revealed no significant differences in mean mind ascription between the medical groups; F(3, 57) = .959; p = .418. As can be seen in Table 3, medical doctors do, on average, ascribe as much mind as do participants with no medical background and the effect that persons with medical background ascribe more mind seems to be mainly driven by the other medical professions. However, if tested with t-test for medical doctors vs. all other medical professions, there is a trend, but no significant difference between professions; t(61) = 1.76; p  = .084.

We were further interested in whether doctors perceive UWS as a state worse than death. We therefore compared 15 doctors from the UWS condition with 22 doctors within the death and corpse condition. Independent t-test showed that doctors perceive UWS as equally tragic (M = 6.00) as an early death (M = 5.05); t(35) = 1.16; p = .256 for themselves and for their families (UWS M = 6.2; early death M = 6.77; t(35) = 1.42; p  = .164).

Regression model

Lastly, we performed a stepwise backward regression analysis into which we entered the factors: age (as a continuous variable), gender (coded with 0/1), subjective knowledge (ranging from 0 to 7), religiosity index (ranging from 0 to 7) and socio-economical status (dummy coded). Backward exclusion resulted in a model that included the factors age, religiosity and socio economic status. The factors gender and subjective knowledge were excluded, since their removal did not significantly reduce the variance explained by the regression model. The final model was highly significant (F (7/210) = 5.39; p < 0.001). Together, the factors are able to explain 15.2% of the variance in mind ascription for UWS David (see Table 4). Age and religiosity were individually significant, younger people and more religious people ascribing more mind, whereas none of the socio economic status categories had an individual effect.

Discussion

We assessed to what extent German participants ascribe mental functions to a UWS patient compared to a deceased or a healthy person, what factors influence this ascription, and how the results compare to a previous US study. In particular, we analyzed the possible role of cultural differences and religiosity in comparison to the US study, as well as the influence of age, gender, socio-demographics, knowledge about and familiarity with UWS patients and medical expertise in the German sample.

Therefore, implicit dualism seems indeed not as widespread a phenomenon in Germany as it is in USA. However, at least for some German participants the line between life and death for these patients may likewise be somewhat blurred. Concerning the manipulation check, we excluded 72 participants who had given the wrong answerer to the question of what happened to David in the vignette story. In the death vignette one was excluded because he stated that David was alive, 9 thought he had survived with severe brain damage (which would be the correct answer for the PVS vignette). In the life vignette 15 were excluded because they said David survived with severe brain damage. In the PVS vignette however, 43 participants (42,5% of all participants failing the manipulation check) answered that David had died. Fischer's exact test confirms that this is significantly more than in the other vignettes ( p  < 0.000). Given the description of the PVS vignette with the very severe brain damage and no hope of recovery, stating that David was dead might not have been a real mistake. Maybe some of the participants actually thought that, while the body was still alive, the person David had died. This is of course a speculation, but if so, the practice of excluding these participants from the study might have actually excluded mostly participants that engage in active dualism. Further studies could address this issue by asking the participants to explain their choice of answer.

Differences in the amount of dualism in different societies are in fact documented within previous studies: For example, dualism is widespread in the USA [ 42, 43], whereas Demertzi and colleagues [ 44] comparing dualism beliefs between an Edinburgh-sample (Scotland) and a Liège-sample (Belgium) found substantial differences, with dualism being significantly more common in Edinburgh. To the best of our knowledge, no study has directly compared dualism beliefs for USA and Germany so far, but the more general role of religion has been subject to various studies. Verweij [ 45], for example, points out, that there is an ongoing secularization within all Western countries, except the United States - the only Western culture relatively untouched by secularization.

Gray also argued that 'there may also be other variables operating in perception of UWS patients, such as liking and familiarity' [ 9], (p.279). Very recent studies seems to confirm that since Moretta et al. demonstrated, that patients caregivers tend to ascribe more interaction abilities to their relatives than physicians do [ 46]. However, in our study neither familiarity with nor the subjective knowledge about UWS patients influences the mind perception of the participants. There is, however, an effect for a medical background. Gray speculated that it might be possible that 'even doctors may see UWS patients as having less mind than the dead' [ 9] (p.279), a conclusion drawn from the fact that many health care professionals, at least in Belgium, also advocate dualism [ 41]. In our sample, participants with a medical background were explicitly included. This covers physicians as well as nurses, medical technical assistants, physiotherapists, psychologists and paramedics. Mind ascription differed specifically in the UWS condition, with participants with medical background ascribing, contrary to Gray's hypothesis, significantly more mental capacity to UWS patients than to the dead. Similarly, Demertzi asked European paramedical caregivers and medical doctors whether or not they think that a UWS patient can experience pain: Here, about 60% of the participants answered with 'Yes', therefore ascribing this mental ability to the patient [ 41]. Kuehlmeyer and colleagues investigated the same question in German and Canadian physicians and here as many as 70% ascribed the ability to feel pain to UWS patients. Another 51% believed that patients are able to feel touch and 21% of the physicians even were convinced that UWS patients can experience dreams [ 47].

Another difference between the German and the US study is the correlation between perceived tragedy of the situation and mind ascription. In the USA people find the state of UWS the more adverse the less mind they ascribe to the patients, whereas in Germany, the opposite is true. This could result from the general value system in which the two correlated variables are embedded [ 55]. Coming from the most individualistic culture, US participants might prefer the possibility of conscious experience (which includes suffering) over experiencing nothing. In Germany, as a less individualistic culture, the correlation is also significant but in the opposite direction, suggesting that Germans perceive UWS as more tragic when ascribing more mind - maybe taking into account that with more mental abilities the possibility of conscious suffering also increases. If this is indeed a cultural phenomenon, than it would be interesting to see whether this judgment becomes even more pronounced within collectivist and perhaps particularly Buddhist societies. However, it is also possible, that the specific history of Germany (where during the Third Reich disabled persons were viewed as 'unworthy of life' and mass "euthanasia" was performed) could make Germans more reluctant to value any life as worse than death. If so, other otherwise similar societies (e.g. Swiss or perhaps French) with no history of nationalism should rate the tragedy of the situation more like the US participants.

Another concern with wording results from the translation into German: We cannot be sure that the German term 'Wachkoma' (waking-coma), which is the commonly used term for UWS among the German population at large, triggers the same context for Germans as does 'vegetative state' in US Americans. 'Wachkoma' might have a more transient connotation for Germans than 'vegetative state' has for Americans. 'Wachkoma' also contains the word '(a)wake' which implies an improvement to the coma-condition, focusing on the ability of the patients to open their eyes. The 'vegetative' in vegetative state, on the other hand, focuses on the inabilities of the patient and his or her "vegetative condition" which might evoke, and has been suggested to bring up, associations of vegetable-likeness [ 2]. This, in turn might have triggered different mind - sets in participants which might have led to different evaluations of mind between German and American participants. However, the story itself does make it very clear, that David's 'Wachkoma' was very futile in terms of outcome. Thus, further research should aim to avoid these methodological issues by assessing the contexts that are activated due to different term-translations which could also be found with other languages.

Moreover, due to different recruiting methods, we might have divergent selection biases in recruiting the two samples. Neither Gray's nor our sampling rely solely on students but recruited participants also randomly at either public places (Gray) or via link circulation in social media (current study). It is conceivable that the paper-and-pencil questionnaires that Gray et al. used in two of their studies, differ as such from on-line questionnaires in a hitherto unknown way.

Regarding demographic information, very little is available about the US sample. Therefore, we have no means to compare for potentially influencing factors, like educational level and socio-economic status. Nevertheless we were able to compare the samples for mean age and gender distribution: Gray's sample is, on average, younger (m = 26 years, t(213) = 26.21, p < .001) and contained more male participants (about 50%). In our data, there was a significant correlation of age with mind ascription in the UWS condition (r(219) = − 0.33, p < 0.000) where the younger participants ascribed more mind but no differences in mind ascription according to gender. This might suggest that, with our sample being older on average, and younger participants ascribing more mind, we might even have underestimated the differences in mind ascription between the US and the German sample. Additionally, in our sample, the effect of age was not mediated through religiosity or the fact, that younger participants might have easier access to information about UWS since we found no correlation between the self assed religiosity of participants and age (r(221) = .122, p > .05) or between the knowledge about UWS and age (r(218) = .129, p  > .05).

Conclusion

# data[].attributes.attachment_link.title
The living dead? Perception of persons in the unresponsive wakefulness syndrome in Germany compared to the USA

# data[].attributes.attachment_link.description
Inga Steppacher Johanna Kissler Research article Mind perception Morality End of life decisions Dualism Disorders of consciousness DOC Disorders of consciousness TBI Traumatic brain injury UWS Unresponsive wakefulness syndrome VS Vegetative state The online version of this article ( https://doi.org/10.1186/s40359-018-0217-4 ) contains supplementary material, which is available to authorized users.

# data[].attributes.body
What is a human?

# data[].attributes.body
If someone is in a comatose state, are they still considered human?

# data[].attributes.body
This study consisted of 201 volunteers reading about a car accident that ended in three outcomes; dead David, PVS David and alive David. The volunteers then had to agree or disagree with various statements. The results showed that people believe see PVS as being more dead than actually being dead.

# data[].attributes.attachment_link.readable_text
JavaScript is disabled on your browser. Please enable JavaScript to use all the features on this page.

Abstract

Patients in persistent vegetative state (PVS) may be biologically alive, but these experiments indicate that people see PVS as a state curiously more dead than dead. Experiment 1 found that PVS patients were perceived to have less mental capacity than the dead. Experiment 2 explained this effect as an outgrowth of afterlife beliefs, and the tendency to focus on the bodies of PVS patients at the expense of their minds. Experiment 3 found that PVS is also perceived as "worse" than death: people deem early death better than being in PVS. These studies suggest that people perceive the minds of PVS patients as less valuable than those of the dead - ironically, this effect is especially robust for those high in religiosity.

Highlights

► Vegetative patients are seen to have less mental capacities than the dead. ► People focus on the bodies of PVS patients at the expense of their minds. ► Religious people show this effect most strongly, because of their afterlife beliefs. ► PVS is also seen as a state worse than death. ► These findings reveal an irony behind fights to keep PVS patients alive.

Recommended articles Citing articles (0)
View full text

# data[].attributes.attachment_link.title
More dead than dead: Perceptions of persons in the persistent vegetative state

# data[].attributes.attachment_link.description
JavaScript is disabled on your browser. Please enable JavaScript to use all the features on this page. Patients in persistent vegetative state (PVS) may be biologically alive, but these experiments indicate that people see PVS as a state curiously more dead than dead.