Transcript Brain death
Brainstem death
Paulus Anam Ong
Department of Neurology
Foreword
The purpose of medical science is to
prolong life and not to prolong dying
process.
Physician:health provider who are
authorized to define death of the individual
Physician should know the definition of
death in both emergency or normal
situation
Definition of Death
Irreversible loss of the capacity for
consciousness, combined with the irreversible
loss of the capacity to breath”
The irreversible cessation of brainstem function
(brainstem death), whether induced by
intracranial events or result of extra-cranial
phenomena will produce the same clinical state
Brainstem death is equivalent to death of the
individual.
U.K. Criteria for the diagnosis of brainstem death (Working Group convened by the Royal Collage of Surgeons, 1995)
Brainstem death
Brainstem: regulator of respiration and
cardiovascular stabilization
Brainstem death: discontinuity of
peripheral neuronal system through the
brain (absolute for consciousness)
Brainstem death: self-fulfilling prophecy
Diagnosis of Brainstem death
3 step in clinical diagnose of brainstem death:
1. To ascertain that essential condition be
satisfied before considering the diagnosis of
brainstem death
2. Exclude the possibilities of reversible cause
of coma and apnea
3. To ascertain the irreversible absence of
brainstem reflexes and the apnea
Ad 1. Certain condition should be
satisfied
Two Condition required for brainstem death:
1. The patient is deeply comatose and
apnea; unresponsiveness and
maintained on the ventilator
2. The diagnosis should be known and the
condition should be one that is capable
of causing neuronal death and the brain
damage is irreversible
Ad 2. To exclude the reversible
cause of comatose and apnea
Drug intoxication (depressant drugs)
Primary hypothermia
Potential metabolic and endocrine
disturbances as a cause of comatose
U.K Code: Diagnosis of brainstem death
should not be consider with the presence
of above points
Before test the brainstem reflexes
There should be evidence of loss of brainstem
function
Patient is in deeply comatose
There is not abnormal postures (decortication or de-cerebration)
There is no occulocephalic reflex
There is no epileptic seizure
There is no spontaneous breath
Brainstem is still functioning if one of the above
point is present.
5 Brainstem reflexes
Absence of :
1. Pupils: no response to light
2. Cornea: no corneal reflexes
3. Oculocephalic testing (head turning) and
Oculovestibular (caloric) testing
4. Motor response to adequate somatic
stimulation within distribution of cranial
nerve
5. Gag reflex (pharingeal and tracheal
reflexes)
Apnea Test
Prerequisites:
Core temperature >36.5 ‘C
Systolic BP > 90 mmHg
Euvolemia. Option: positive fluid balance in
previous 6 h.
Normal Pco2 > 40 mmHg
Normal Po2. Option: preoxigenation to obtain
arterial P o2 > 200mmHg
Connect a pulse oximeter and discontect the
ventilator
Apnea Test
Deliver 100% O2 6l/min into trachea.
Look closely for respiratory movement (abdominal or chest
excursions that produce adequate tidal volumes)
Measure arterial P o2, Pco2 and pH after approximately 8 min and
reconnect the ventilar.
If respiratory movement are absent and arterial Pco2 is >60mmHg;
the apnea test is (+) support brainstem death
If respiratory movement are observed apnea test is (-)
Connect the ventilator if during testing systolic BP <90mmHg, or
cardiac arrythmia or oxygen desaturation are present; immidiately
analyze arterial blood gases. If Pco2 is >60 mmHg or Pco2 rise
>20mmHg apnea test (+) support brainstem death; if Pco2 is
<60mmHg or Pco2 is <20mmHg over baseline, the result is
indeterminate, additional confirmatory test can be considered.
Repeat of test
Test repeating is done to avoid fault
observation and changes of signs
Interval time of 2 tests range from 25
minutes to 24 hrs depend on hospital
regulation and recommendation accepted
Difficulties in diagnosing brainstem
death
Examination results
Possible causes
1. Fixed pupils
Anticholinergic drugs, muscle relaxing
drug, previous disease
2. Oculo-vestibuler reflex (-) Ototoxic drug, vestibular suppressant,
Previous disease
3. Apnea
Post hyperventilation
Muscle relaxing drug
4. No motor response
“Locked in state”, muscle relaxing drug,
Sedative drugs
5. Isoelectric EEG
Sedative drug, hypoxia, hypothermia,
Encephalitis, trauma
Difficulties in diagnosing brainstem
death
1.
2.
3.
4.
Severe facial trauma
Disease of pupils
Sedative drug used
Severe pulmonary disease
After diagnosis of brainstem death
Withdraw therapeutic and palliative
treatment gradually according to severity
of individual patient
Doubt in:
Primary diagnosis
Cause of brainstem dysfunction may be
reversible (drug and metabolic disorders)
Completeness of clinical test
Do not make diagnosis of brainstem death
Ancillary Testing
No required
USG doppler
MRI
Brainstem Evoke Potential
Electroencephalography
According to Indonesia Doctor
Association (IDI)
Diagnosis of brainstem death should be
made by at least 2 doctor who are
experience in this field
In Indonesia
Anestesiologist, Critical care doctors,
Neurologist and both of them do not
involved in the organ transplant team