Declaring Brain Death in the
Low Resource ED
Elizabeth DeVos MD, MPH, FACEP
Clinical Director, sidHARTe Rwanda
Outline
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History & Background
Preconditions
Clinical Testing Requirements
Additional Testing Options
African Context
History
• 1968: Harvard Medical School, Dr. Beecher Chairman of
committee to:
– “identify the moment of death for patients maintained on mechanical support
to reallocate expensive resources to the living as well as to inform families as to
whether the relatives were alive or truly dead
– “To identify dead people from whom vital organs ethically could be obtained for
transplantation”
• 22nd World Medical Assembly Essential Statement on Human Death
• 1981: President’s Commission
– Study biomedical ethical problems
– Testimony from medical, theological and lay
witnesses
• Uniform Determination of Death Act
– Accepted by most states by late 1980s
http://commons.wikimedia.org/wiki/Category:Polio#mediaviewer/File:IronLung.jpg
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Defining Brain Death
• What it is
• “Diagnosis and
confirmation of death
based on the
irreversible cessation
of functioning of the
entire brain, including
the brainstem”
• What it is not
• Something other than
“regular death”
• Persistent vegetative
state
• A concept to facilitate
organ transplants
Preconditions:
• 1. Brain injury capable of causing
irreversible cessation of brain
function
• 2. Absence of:
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–
–
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Hemodynamic shock
Drug intoxication
Hypothermia
Significant, reversible metabolic or
electrolyte derangement
• 3. Intact neuromuscular function
(Not under neuromuscular blockade)
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Preconditions for Testing
Confounders to Testing
Established Etiology for Coma
Hypothermia
Absence of Hemodynamic Shock
CNS Depressing Drugs
Absence of Reversible Etiologies
to Explain Coma
High Cervical Spine Injury
Competent Health Professional
Performing Clinical Exam
Evidence of Acquired or
Iatrogenic Neuromuscular
Paralysis
Severe Acid-Base, Electrolyte or
Endocrine Abnormality
Competent Health Professional
Performing and Interpreting
Ancillary Labs and Testing
Shock
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Example Observation Periods for
Ventilated Patients
>4
Hours
Apneic coma
after major
neurosurgery
Confirmed
aneurysm with
second in
hospital SAH
>6
Hours
Head Injury
(no secondary
hematoma, shock
or brain hypoxia)
Spontaneous ICH
(no secondary
hypoxic injury)
>24
Hours
50-100
Hours
Brain Hypoxia
(drowning,
cardiac arrest, etc)
Any of the above
with suspicion of
drug intoxication
and lack of ability
to screen
Adapted from Pallis C, Harley DH. The ABC of brainstem death. 2nd ed. BMJ Publications, 1996
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Clinical Testing
Loss of consciousness
No spontaneous movements (excluding spinal reflexes)
No motor responses in cranial distribution
No brainstem reflexes
– No pupillary light reflex-pupils mid-position or greater (‘fixed
dilated pupils’)
– No corneal reflex
– No gag/pharyngeal reflex
– No cough/tracheal
• Vestibulo-ocular (‘cold caloric’) test
• Oculo-cephalic (‘dolls eye’) test
• Loss of capacity to breathe
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Apnea testing
• Hypercarbia maximally stimulates respiratory
centers in the brain.
• Apneic oxygenation diffusion test is safe
– Limited comparative evidence between tests
– Without testing PaCO2 may not catch apnea due
to post hyperventilation
• Recommended to do after all other tests
– Hypercarbia could decrease cerebral blood flow in
potential brain death
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Additional Testing
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isoelectric EEG
absent brain blood flow
absence of brain perfusion
absence of cerebral metabolic activity
absent brainstem evoked potentials after wave 1
evidence of tonsillar herniation by neuro-imaging
As an adjunct to, not substitute for clinical determination
• Use and extent of complementary testing may vary by
jurisdiction
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Most country guidelines are similar:
• Unresponsive coma with an established
etiology
• Absence of reversible conditions
• Absence of cortical or brainstem mediated
motor responses
• Absent brainstem reflexes
• Loss of the capacity to breathe
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Where there is variation
How to do apnea testing
Depressant Drugs
Observation time
Age-related criteria
Required level of physician expertise
How to address anoxic-ischemic brain death
Effect of therapeutic hypothermia
Confirmatory, supplemental or ancillary testing
(EEG, brain blood flow testing)
• Time of death
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AAN 10 year literature after 1995 guideline
• No reports of patients recovering neurologic
function who met 1995 AAN practice
parameter
• No sufficient evidence for:
– What is adequate observation period?
– Comparative safety techniques for determining
apnea
– Utility of MRI/MRA
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Reflex spinal movements
• Complex, non-brain mediated motor and spontaneous
movements and non-respiratory triggering of the ventilator
may occur in patients who are brain dead
• Can confuse and upset family and nontreating physicians
• Up to 75% of patients approaching brain death
– Finger jerk, muscle stretch
– Spinal automatisms
• “Lazarus sign” ‘flex arms and shoulders, lift arms, dystonic hand
posturing, crossing of hands”
– Case reports of low-frequency gasps with CPAP may be reflex
motor activity
• Use Supraorbital ridge pressure to avoid stimulation of local limb
spinal reflex activity when assessing pain response
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Brain Death Evaluation: AFEM Handbook
• 2 providers, at least 1 senior
• Prerequisites:
– Absence of clinical brain function with potential cause
known and demonstrated as irreversible
– Clinical or neuroimaging evidence of CNS catastrophe
– Exclusion of potentially reversible circulatory,
metabolic, and endocrine causes of coma
– No toxicological explanation (including iatrogenic)
– Core temp >36 C (regional variation, may require
active warming)
– Apnea
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Brain Death Evaluation: AFEM
Handbook
• Coma (unresponsiveness)
– No cerebral motor pain response (supraorbital, nailbed)
• No Brainstem Reflexes
– Pupils (mid-dilated 4-9mm)
– No response to bright light (CN II-III)
– Ocular Movement
• Doll’s eyes (occulocepthalic reflex)
• Caloric testing (Occulovestibular )
– Facial Sensation and Motor
• No corneal reflex
• No jaw reflex
– Pharyngeal/Tracheal Reflexes
• No gag reflex
• No cough to suctioning
• Apnea for 6-24 hours
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Doll’s Eyes (Occulocephalic Reflex)
Normal eyes move opposite to head movement
BUT remains neutral in death (CN III and VI)
HEAD
EYES
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HEAD
EYES
COLD WATER TESTING
(Vestibulo-Occular Test)
NORMAL
BRAIN DEATH
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Apnea testing
• Protocol important to avoid secondary hypoxic brain
injury
• Verify Temp >36C, SBP >90, euvolemia, PCO2 and PO2
• Attach pulse oximeter
• Disconnect ventilator while giving 6 lpm through
intratracheal catheter at the carina
– Repeat blood gas at 5-8 min (or local guideline)
– Some require 10 min and SBP >100 throughout
• STOP TEST if hypotension or cardiac instability occurs
• +: No respiratory movement and PaCO2>60 mmHg(or
increases 20 mmHg in some areas)
• -: Respiratory movement observed
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What about confirmatory tests?
• Cerebral Blood Flow
– Absence of CBF is conclusive of
brain death
– Requires moving to radiology for
sophisticated scans
– Blood flow DOES NOT rule out
brain death
• EEG
– Different local requirements
– Can be confusing
• Altered by hypothermia, drugs,
etc
• Possible to have absent cortical
function, isoelectric EEG and still
have brainstem function
• Brainstem Auditory Evoked
Responses
– Requires intact auditory
nerve and pt without
previously existing brainstem
dysfunction
– Simple, accurate, inexpensive,
but requires trained
personnel and equipment
– Negative test doesn’t
diagnose death without
cortex testing
– Not sufficient alone
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What about Africa?
Country
Law
Apnea
Guideline Test
# MD
Observation Confirmatory
(hr)
Test
Egypt
A
A
A
A
A
Unknown
Ghana
A
A
A
A
A
Unknown
S. Africa
P
P
PCO2
2
A
Optional
Tanzania
A
P
A
1
A
Mandatory
Tunisia
P
P
DVO
1
A
Optional
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Adapted from: Wijdicks EF, Brain Death Worldwide: Accepted Fact But No
Global Consensus in Diagnostic Criteria. Neurology, 2002:58; 20-25.
Wijdicks EF, Brain Death Worldwide: Accepted Fact But No
Global Consensus in Diagnostic Criteria. Neurology,
2002:58; 20-25.
• Recommendations
– International task force could address
inconsistencies in guidelines
– Develop apnea test criteria
• ie could do serial measurement of PCO2 at bedside
– Consider reducing observation periods and
confirming tests
• Challenges
– Cultural and religious barriers
– Difficulty getting country buy in
– Concern about errors and MD qualifications
Summary
• Brain death is the permanent loss
of function of the entire brain,
including brainstem
• Clinical criteria can be used to
identify brain death
• Confirmatory tests can help in
confusing situations
• African EDs can add their
experiences to the literature as we
gather more information
References
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Dixon T and Malinoski D. Western J Emerg Med. 2009; 10 (1): 117
Guidelines for the determination of death: report of the medical consultants on the diagnosis
of death to the President’s commission for the study of ethical problems in medicine and
biochemical and behavioral research. JAMA 1981;246:2184 –2186.
Laureys, S. Death, unconsciousness and the brain. Nature Reviews Neuroscience. Nov 2005; 6
(11): 899-909
Pallis C, Harley DH. The ABC of brainstem death. 2nd ed. BMJ Publications, 1996
Pike R, McCurdie F, Kahn D. Brainstem Death in the Intensive Care Unit. The Southern African
Journal of Critical Care. 1992: 8(1); 8-11
Practice parameters for determining brain death in adults (summary statement). The Quality
Standards Subcommittee of the American Academy of Neurology. Neurology. 1995;45
Shemie S et al. International Guideline Development for the Determination of Death.
Intensive Care Med. 2014; 40: 788-797
Uniform Determination of Death Act, 12 uniform laws annotated 589 (West 1993 and West
suppl 1997).
Wijdicks EF, Brain Death Worldwide: Accepted Fact But No Global Consensus in Diagnostic
Criteria. Neurology, 2002:58; 20-25.
Wijdicks EF, Varelas, P, Gronseth G, and Greer D. Evidence-based guideline update:
Determining brain death in adults. Neurology, 2010; 74:1911-1918.