Marino The ICU Book 4e, IE

811

Disorders of Consciousness

Table 44.5

Checklist for Brain Death Determination in Adults

Check ( ✔ )

Instructions:

Item if

The patient can be declared legally dead if Steps 1–4 are confirmed, or there is a positive confirmatory test. Step 1: Prerequisite to Exam: All of the following conditions should be corrected before beginning the brain death evaluation. • Hypotension (mean arterial pressure < 65 mm Hg) • Hypothermia (core temp < 32°C or < 90°F)

Confirmed

❏

• Hypothyroidism • Hypoglycemia • Effects of CNS depressant drugs

Step 2: Establish the Cause of Coma: The cause of coma is known, and is sufficient to account

❏

for irreversible brain death.

Step 3: Absence of Brain and Brainstem Function: This step involves two sequential exams. There is no agreement about the length of time required between exams, but 6 hours is a popular choice. A. The patient is comatose (unaware and unresponsive). • Absent pupillary response to bright light • Absent corneal reflex • Absent gag and cough reflexes • Absent oculocephalic reflex • Absent deviation of eyes with cold water stimulation of the tympanic membrane Step 4: Absence of Spontaneous Breathing Efforts: There are no spontaneous breathing efforts when the B. The following brainstem reflexes are absent:

First Second Exam Exam

❏ ❏ ❏ ❏

❏

arterial PCO 2

is 20 mm Hg above the patient’s baseline

level (positive apnea test).

Step 5: Consider Confirmatory Tests: † Confirmatory tests may be necessary when Steps 1–4 cannot be completed or unequivocally interpreted.

† Confirmatory testing can include: electroencephalography, transcranial Doppler flow study, somatosensory evoked potentials, brain scan with technetium-99m, or cerebral angiography.

From References 30–32.