What are the guidelines for confirming brain death?

Guidelines for Confirming Brain Death

Brain death determination requires two complete neurological examinations, including apnea testing, performed by different attending physicians and separated by an observation period, to confirm irreversible cessation of all brain function. 1

Prerequisites for Brain Death Determination

• Establish a known, irreversible cause of coma before proceeding with brain death testing 2, 1
• Correct all confounding factors that could affect neurological assessment:
  • Normalize blood pressure and core temperature (>35°C) 2, 1
  • Correct metabolic disturbances 2, 1
  • Discontinue sedatives, analgesics, neuromuscular blockers, and anticonvulsants for an appropriate time based on elimination half-life 1
  • Ensure medication levels are in low to mid-therapeutic range 1

Clinical Examination Components

• Complete neurological examination must demonstrate:
  • Coma (unresponsiveness to all external stimuli) 2, 3
  • Absence of all brainstem reflexes (pupillary, corneal, oculocephalic, oculovestibular, gag, cough) 2, 3
  • Absence of motor responses to pain in all extremities 2, 3

Apnea Testing Procedure

• Pre-oxygenate with 100% oxygen for 5-10 minutes 1, 4
• Disconnect from ventilator while providing oxygen via catheter or T-piece 1, 4
• Monitor for respiratory effort while allowing PaCO₂ to rise 2, 4
• Confirm brain death when:
  • PaCO₂ rises to ≥60 mmHg or ≥20 mmHg above baseline 2, 1
  • No respiratory effort is observed 2, 1
• If the apnea test cannot be completed safely (e.g., hypoxemia with O₂ saturation <85%), the patient should be placed back on ventilator support, and ancillary studies should be performed 2, 4

Observation Period Requirements

• For term newborns (37 weeks gestation to 30 days): 24-hour observation period between examinations 2
• For infants and children (30 days to 18 years): 12-hour observation period between examinations 2
• For preterm infants less than 37 weeks gestational age: insufficient data exists to make recommendations 2

Ancillary Testing

• Ancillary tests are NOT required to establish brain death unless 2, 1:

  • Components of the clinical examination cannot be completed safely 2
  • Uncertainty exists about the results of the neurological examination 2
  • Medication effects may interfere with evaluation 2
  • Apnea testing cannot be performed safely 2

• Acceptable ancillary tests include 1:

  • Electroencephalogram (EEG) showing electrocerebral silence 2, 1
  • Cerebral blood flow studies showing absence of cerebral blood flow 2, 1
  • Four-vessel cerebral angiography 1
  • Radionuclide cerebral blood flow study 1

Declaration of Death

• Death is declared after confirmation and completion of the second clinical examination and apnea test 2
• When ancillary studies are used, documentation of components from the second clinical examination that can be completed must remain consistent with brain death 2
• The clinical examination should be carried out by experienced clinicians familiar with infants and children, with specific training in neurocritical care 2

Documentation Requirements

• Record all prerequisites and confounding factors addressed 1
• Document detailed findings of both neurological examinations, including apnea testing 1
• When ancillary tests are used, document specific findings consistent with brain death 1

Common Pitfalls to Avoid

• Failure to identify and correct confounding factors that can mimic brain death 3, 5
• Variability in institutional protocols leading to inconsistent brain death determination 6
• Performing apnea testing without proper preparation or safety measures 4
• Relying solely on ancillary tests without completing the clinical examination components that can be performed safely 2, 5
• Inadequate observation periods, particularly in pediatric patients 2