Brain death
From IDWiki
- A neurological determination of death (NDD)
Procedure
Prerequisites
- Known cause of neurological death
Examination
- Deep unresponsive coma with bilateral absence of motor responses
- Excluding spinal reflexes
- Absence of brainstem reflexes, as defined by absent gag and cough reflexes and the bilateral absence of
- Corneal responses
- Pupillary responses to light, with pupils at mid-size or greater
- Vestibulo-ocular responses
- Absence of respiratory effort based on the apnea test
- Absence of confounding factors
Apnea test
- Preoxygenate with 100% oxygen
- Stop ventilator and monitor for signs of effort
- If the ABG shows a PaCO2 ≥60 mmHg (and ≥20 mmHg above pre-apnea levels) and the pH ≤7.28, then the test is considered positive
Confounding factors
- Unresuscitated shock
- Hypothermia (core temperature < 34°C)
- Severe metabolic disorders capable of causing a potentially reversible coma
- Severe metabolic abnormalities, including glucose, electrolytes (including phosphate, calcium and magnesium), inborn errors of metabolism, and liver and renal dysfunction
- If it may be playing a role, then it should be corrected before neurological determination of death is made
- Peripheral nerve or muscle dysfunction
- Clinically significant drug intoxications (e.g., alcohol, barbiturates, sedatives, hypnotics)
Transplantation
- For transplant, the examination must be done by two physicians (this is required by law), but may be done concurrently
Further Reading
- Severe brain injury to neurological determination of death: Canadian forum recommendations. CMAJ. 2006;174(6)S1-S12.
