375 Ch 374. Brain Death and Disorders of Consciousness

Brain death (death by neurological criteria, DNC) = irreversible cessation of ALL brain function including brainstem → legally + ethically equivalent to cardiopulmonary death in most jurisdictions；AAN 2010 + updated 2023 (pediatric + adult) guidelines；three criteria: (1) irreversible coma of known etiology, (2) absent brainstem reflexes, (3) apnea；confounders must be excluded: hypothermia, severe metabolic/electrolyte/endocrine disturbance, drug intoxication/sedatives, neuromuscular blockade, severe hypotension；clinical examination + apnea test (PaCO2 ≥ 60 mmHg or ≥ 20 mmHg over baseline with no respiratory effort)；ancillary tests (EEG, cerebral blood flow studies, TCD, CTA) — when apnea test contraindicated or clinical exam confounded；organ donation ethical considerations；disorders of consciousness (DOC) = spectrum: coma → UWS (vegetative state) → MCS (minimally conscious) → emergence；prognostication is critical and humbling — “covert consciousness” detected in some by fMRI/EEG paradigms。