1. Coma

• Noxious stimuli without motor response (except spinal reflexes)

2. Absent Brainstem Reflexes

• Absent pupillary response to light bilaterally
• Absent oculocephalic reflex (doll’s eyes)
• Absent oculovestibular reflex (caloric reflex test bilaterally)
• Absent corneal reflex
• Absent facial muscle contraction to noxious stimulus
• Absent gag and cough reflex

3. Apnea Test

• Absent respiratory drive despite CO2 challenge (pCO2>60mmHg)

4. Vital signs

• Core body temperature 36-37^oC (normothermia)
• SBP ≥ 90mmHg
• PO2 >200mmHg and PaCO2 ~40mmHg → before discontinue ventilator use
• Verified absence of pharmacologic agent simulating brain death