BUMC Basics.pdf - Anesthesia Home

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BRAIN DEATH EXAM
• Can order brain death exam order set and it guides you
through the following:
• Brain death is a clinical diagnosis
• Need to exclude the presence of
exogenous/endogenous toxins
• Patient can’t be hypothermic: Need to warm them up to
declare them brain dead
• Exam has 3 components (need to have all of the
following): 1) Coma 2) Absent brain stem reflexes 3)
Apnea test
1. Coma: Needs to be at least 6 hours if patient has a
structural lesion and 24 hours if patient has anoxic
brain injury
2. Brain stem reflexes:
- Absent motor response
- Pupils are midposition or dilated (4-9 mm), absent
light reflex, doll’s eye maneuver
- Absent corneal reflex
- Absent oculovestibular reflexes (30-60 cc ice water
in ear canal results in no movement; in normal
person, fast beat is described by COWS: cold
opposite, warm same, in coma, a response would be
seen if eye slowly moves toward ear irrigated with
cold water)
- Absent jaw jerk
- Absent gag reflex
- Absent cough with tracheal suctioning
- Absent sucking or rooting reflex
If all brain stem reflexes are absent, proceed to
3. Apnea test: Pre-oxygenate at 100% FiO2 x 5-10
minutes. Would like pCO2 to be around 40 to begin
with if possible. Then, disconnect from ventilator
support for 8-10 minutes (deliver O2 at 8-10L/min, a
small canula is placed down the ET tube) and watch
for respirations. A positive test is absence of any
respiratory response and a post test ABG with PaCO2
>60 or 20 mmHg greater than baseline.
4. Confirmatory testing (Not mandatory):
- Brain flow study: nuclear scan to evaluate for
cerebral blood flow (no flow when ICP exceeds SBP)bedside
(pitfall – does not evaluate posterior
circulation)