2. What is brain death?
• Irreversible cessation of all functions of the entire
brain, including the brain stem
• Medically and legally, death can be declared
Ref:
1. Guidelines for the determination of brain death in infants and children. American Academy of
Paediatric Task Force on Brain Death in children. Paediatrics 2011:128:e720-e740
2. Consensus statement on Brain Death 2003. Ministry of Health, Academy of Medicine Malaysia and
Malaysian Society of Neurosciences
3. Pre-conditions
• Deep coma, apnoeic and ventilator-dependent
• Cause of coma fully established and sufficient
to explain the status of patient
• Irremediable structural brain damage
Deep coma: state of unconsciouness which cannot be awakened, no respond to external stimuli and lacks
normal sleep-wake cycle
Persistent vegetative state (PVS): severe brain damage, characterised by partial arousal without true
awareness, demonstrates sleep-wake cycle but completely lack cognitive fx
Ref:
1. Guidelines for the determination of brain death in infants and children. American Academy of Paediatric Task
Force on Brain Death in children. Paediatrics 2011:128:e720-e740
2. Malaysia Paediatric Protocol 3rd edition
4.
5.
6. Examination criteria
Essentially designed for term babies and pediatric/adolescent age group
• >37 weeks gestational age to 18 y/o
• Core temperature >35’C
• Normotensive without volume depletion
• Free from metabolic disturbances capable of
causing coma
• Free from medications can interfere with the
neurologic examination e.g. sedatives,
analgesics, antiepileptics, and paralytic agents
7. Examination criteria
• Two examinations are performed by two
different attending physicians (at least 3 years
of postgraduate clinical experience and
trained in brain death assessment) preferrably
pediatricians, anaesthesiologists, neurologists, neurosurgeons.
Doctors involved in organ donation not allowed to certify brain death
– Examinations are separated by an observation
period of:
• Term newborns to 30 days: 24 hours apart
• Children >30 days to 18 years: 12 hours apart
8. Diagnostic criteria (ALL to be fulfilled)
• Glasgow coma scale 3/15
• Apnoeic, confirmed by apnoea test
• Absent brain stem reflexes confirmed by the
following tests:
11. Confirmatory tests
• Cranial nerves
– V and VII: Hold the eyelid open, touch the cornea
with gauze, tissue, or the tip of a swab
– II and III: pupils fixed and dilated
– IX and X: absent cough and gag during suction
– III and VI: doll’s eye reflex
13. Doll’s eye reflex
• Hold the eyelids open. The examiner moves
the patient’s head from side to side forcefully
and quickly. In brain death, the eyes always
point in the direction of the nose and do not
lag behind or move
14.
15. Cold water/warm water caloric test
• Testing nerve III, VI and VIII
• Contraindicated if TM perforated
– Head is elevated to 30’ during the irrigation of the
ear canal on each side with 50 ml of ice/warm
(>44’C) water
– Allow 1 minute after injection
– Tonic deviation of the eyes in the direction of cold
stimulus is absent
– COWS: Cold Opposite, Warm Same.
Cold water = FAST phase of nystagmus to the side Opposite from the cold water filled ear
Warm water = FAST phase of nystagmus to the Same side as the warm water filled ear
16.
17.
18. Apnea test
• Ensure normal pCO2, normothermia > 35’C,
normotensive
– Method:
• Pre O2 100% oxygen for 5-10 minutes
• Disconnect from ventilator
• Deliver 100% O₂ via ETT at 6 L/min
• Measure PCO₂ after 5 minutes and again after 8 minutes
if PCO₂ has not exceeded 60 mmHg
• Re-connect to ventilator after the test
• Do not exceed 10mins
• The apnoea test is positive when there is no respiratory
effort with a PaCO₂ of ≥ 60 mmHg.
19. Pifalls in assessment
• Difficult in patients with severe facial trauma,
pre-existing pupillary abnormalities, toxic levels
of sedative drugs
• If drug level is below the therapeutic range, brain
death can be declared
• Spontaneous and reflex movements may be
observed in a person with brain death e.g. finger
jerks, toe flexion and persistent Babinski
response – spinal in origin and does not preclude
the diagnosis of brain death
20. Take home message
• Brain death defined as cessation of all
functions of the entire brain
• Need to correct all possible causes of brain
death e.g. metabolic, drugs, temperature,
hemodynamics etc
• 3 diagnostic criteria to confirm brain death:
GCS 3/15, apnea (confirmed by apneic test),
absent brain stem reflexes
Editor's Notes
ACCCM (American College of Critical Care Medicine) -
Preterm infants – age-related neurologic fx: difficulty with examining newborns (difficult to assess their level of consciousness and brainstem fx and a possibility of maturation lag, need to be based on serial neurological findings however remained controversial (pupillary reflex absent at <32w, occulopcephalic reflex absent at <32w)
ACCCM (American College of Critical Care Medicine) -
In the midbrain: Occulomotor, Trochlear
In the pons: Facial, Trigeminal (motor)
In the medulla: CN 9, 10, 11 and 12
If the water is warm (44 °C or above) endolymph in the ipsilateral horizontal canal rises, causing an increased rate of firing in the vestibular afferent nerve. This situation mimics a head turn to the ipsilateral side. Both eyes will turn toward the contralateral ear, with horizontal nystagmus (quick horizontal eye movements) to the ipsilateral ear.
If the water is cold, relative to body temperature (30 °C or below), the endolymph falls within the semicircular canal, decreasing the rate of vestibular afferent firing. This situation mimics a head turn to the contralateral side. The eyes then turn toward the ipsilateral ear, with horizontal nystagmus to the contralateral ear.
