Historical Perpective

Uncertainty of death has been historically expressed as fear of premature burial, a likely source of the custom of wakes and attendance on the recently dead. In 18th century France, brass pins under finger and toenails was a test for death, but the odor of decay was held more certain (a reasonable sign of postmortem change).

Legal/Clinical Criteria

Currently, brain death (irreversible coma) is generally accepted as the legal/clinical definition of somatic death.

Brain death criteria can be applied only in the absence of hypothermia, hypotension, metabolic or endocrine abnormalities, neuromuscular blockers, or drugs known to depress brain function.

The criteria for brain death is defined in the Neurology Journal article: Eelco F.M. Wijdicks EFM et alEvidence-based guideline update: Determining brain death in adults Report of the Quality Standards Subcommittee of the American Academy of Neurology

A toxicology screen is required if sufficient time since admission (at least 3 days) has not elapsed to exclude a drug effect. Moreover, the patient should be observed long enough to establish with reasonable certainty the irreversible nature of the injury. Generally accepted clinical criteria for brain death include the following:

  1. Coma

  2. Absent motor activity, including no decerebrate or decorticate posturing; spinal cord reflexes may be preserved in some patients

  3. Absent brainstem reflexes, including no pupillary, corneal, vestibuloocular (caloric), or gag (or cough) reflexes

  4. Absence of ventilatory effort, with the arterial CO2 tension at least 60 mm Hg or 20 mm Hg above the pretest level.

Repeating the examination (not less than 2 h apart) is optional. In the United States the required number of physician observers varies by state (Florida requires two), as does the level of expertise (Virginia requires a neurologist or neurosurgeon to make the determination). The apnea test should be reserved for last because of its detrimental effects on intracranial pressure. Confirmatory test findings that may be helpful but are not required include an isoelectric electroencephalogram, absence of brainstem auditory evoked potentials, and absence of cerebral perfusion as documented by angiographic, transcranial Doppler, or radioisotopic studies.

Biological Considerations

Death is the cessation of all biological functions that sustain a living organism.

Cultural Considerations

In human societies, the nature of death and humanity's awareness of its own mortality has for millennia been a concern of the world's religious traditions and of philosophical inquiry. This includes belief in resurrection (associated with Abrahamic religions), reincarnation or rebirth (associated with Dharmic religions as well some strands of Judaism), or that consciousness permanently ceases to exist, known as oblivion.

Commemoration ceremonies after death may include various mourning or funeral practices. The physical remains of a person, commonly known as a corpse orbody, are usually interred whole or cremated, though among the world's cultures there are a variety of other methods of mortuary disposal. In the English language, blessings directed towards a dead person include rest in peace, or its initialism RIP.

Many societies have tried to prevent or slow postmortem decomposition. Mummification, the drying or embalming of the corpse as practised in pharaonic Egypt for reasons of religion, led to the understanding that the root of decomposition was the gut, which was removed prior to the application of chemical drying agents and preservatives.1

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