2. Brain Death

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The diagnosis of Brain

Death

The diagnosis of Brain

Death

Review article

RMLH, Delhi

Indian J of Crit Care Med (Jan-Mar) 2009: Vol13; issue 1

Review article

RMLH, Delhi

Indian J of Crit Care Med (Jan-Mar) 2009: Vol13; issue 1


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Brain injury and Brain DeathBrain injury and Brain Death

BRAIN INJURY

BRAIN DEATH

Brain death means that life support is futile, and

brain death is the principal prerequisite for the

donation of organs for transplantation


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Evolution of the criteria(BRAIN

DEATH)

Evolution of the criteria(BRAIN

DEATH)

Historically:

Presence of putrefaction or decapitation,

Failure to respond to painful stimuli, or

Apparent loss of observable cardio

respiratory action

Historically:

Presence of putrefaction or decapitation,

Failure to respond to painful stimuli, or

Apparent loss of observable cardio

respiratory action

Widespread use of mechanical ventilators has

changed this definition


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Ad hoc committee at Harvard

Medical School: 1968

Ad hoc committee at Harvard

Medical School: 1968

Unresponsiveness and lack of

receptivity

Absence of movement and breathing

Absence of brain-stem reflexes

Coma whose cause has been identified

Unresponsiveness and lack of

receptivity

Absence of movement and breathing

Absence of brain-stem reflexes

Coma whose cause has been identified


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Recent definitionRecent definition

Irreversible loss of all functions of the

brain ( includes brainstem)

Three essential findings in brain death

Coma

Absence of brainstemreflexes

Apnoea

Irreversible loss of all functions of the

brain ( includes brainstem)

Three essential findings in brain death

Coma

Absence of brainstemreflexes

Apnoea


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Diagnosis of brain deathDiagnosis of brain death

P

rimarily clinical Two assessments of brain stem

reflexes

Single apnoea test

P

rimarily clinical Two assessments of brain stem

reflexes

Single apnoea test

Conclusive of diagnosis if properly performed in

patients one year of age or older


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Determination of Brain DeathDetermination of Brain Death

History or Physical examination findings that provide aclearetiologyetiology of brain dysfunction

Exclusion of any confounding factorsconfounding factors Shock/Hypotension

Hypothermia T < 32degree C

Drugs

Brainstem encephalitis

GB syndrome Encephalopathy ( Hepatic , uramia, Hyperosmolar coma)

Severe hypophosphatamia

History or Physical examination findings that provide aclearetiologyetiology of brain dysfunction

Exclusion of any confounding factorsconfounding factors Shock/Hypotension

Hypothermia T < 32degree C

Drugs

Brainstem encephalitis

GB syndrome Encephalopathy ( Hepatic , uramia, Hyperosmolar coma)

Severe hypophosphatamia


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Determination of Brain Death

contd

Determination of Brain Death

contd

Performance of a complete Neurologicalcomplete Neurological

examinationexamination Absence of movement ( spinal reflex may be present)

Absent pupillary reflex (pupils need not be equal ordialated )

Absent Corneal, oculocephalic, cough and gag reflexes

Absent oculovestibular reflex ( 20 to 50ml ice water) Failure of heart response to atropine( 5 beats after 1-2mg iv atropine)

Absent respiratory efforts in presence of hypercarbia

Performance of a complete Neurologicalcomplete Neurological

examinationexamination Absence of movement ( spinal reflex may be present)

Absent pupillary reflex (pupils need not be equal ordialated )

Absent Corneal, oculocephalic, cough and gag reflexes

Absent oculovestibular reflex ( 20 to 50ml ice water) Failure of heart response to atropine( 5 beats after 1-2mg iv atropine)

Absent respiratory efforts in presence of hypercarbia


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A

pnoeaA

pnoea testtestA

pnoeaA

pnoea testtest

Conditions to be met :

Core temp > 36-5C or 97.7 F

Euvolemia. ( positive fluid balance in

previous 6hrs)

Normal PCO2 ( PCO2 >40mm Hg) Normal PaO2 ( arterial PaO2>200mm Hg)

Conditions to be met :

Core temp > 36-5C or 97.7 F

Euvolemia. ( positive fluid balance in

previous 6hrs)

Normal PCO2 ( PCO2 >40mm Hg) Normal PaO2 ( arterial PaO2>200mm Hg)


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Procedure for Apnoea testProcedure for Apnoea test

Connect pulse oximeter and disconnect

ventilator

Deliver 100% oxygen,

Look for any respiratory movements

ABG after 8 min ( PaO2, PCO2, pH )

Connect pulse oximeter and disconnect

ventilator

Deliver 100% oxygen,

Look for any respiratory movements

ABG after 8 min ( PaO2, PCO2, pH )


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Positive testPositive testPositive testPositive test

Absent respiratory movements

Arterial PCO2 is >60mm Hg ( 20 mm Hg increaseover a baseline)

Supports the diagnosis of Brain Death

When appropriate a 10min apnoea test performedafter pre-oxygenation for 10min with FiO2 of 1.0

and normalization of PaCO2 to 40 mm Hg.

Negative test: Visible respiratory movements

Absent respiratory movements

Arterial PCO2 is >60mm Hg ( 20 mm Hg increaseover a baseline)

Supports the diagnosis of Brain Death

When appropriate a 10min apnoea test performedafter pre-oxygenation for 10min with FiO2 of 1.0

and normalization of PaCO2 to 40 mm Hg.

Negative test: Visible respiratory movements


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Problems during testingProblems during testing

Systolic BP 60 supports the diagnosis of brain death


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Assessment of Brain stem

reflexes

Assessment of Brain stem

reflexes PUPILS:

No response to bright light

Midposition ( 4mm) to dialated ( 9mm)

Cranial nerve 2 and 3

OCULAR MOVEMENT: No oculocephalic reflex ( test only when no fracture or

instability of the cervical spine or skull base is apparent)

No deviation of eyes to irrigation in each ear with 50ml of

cold water ( TM intact; allow 1 min after injection and 5 minbetween testing on each side )

Cranial nerve 3,6 and 7

PUPILS: No response to bright light

Midposition ( 4mm) to dialated ( 9mm)

Cranial nerve 2 and 3

OCULAR MOVEMENT: No oculocephalic reflex ( test only when no fracture or

instability of the cervical spine or skull base is apparent)

No deviation of eyes to irrigation in each ear with 50ml of

cold water ( TM intact; allow 1 min after injection and 5 minbetween testing on each side )

Cranial nerve 3,6 and 7


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Brain stem reflexesBrain stem reflexes

FACIAL SENSATION AND FACIAL

MOTOR RESPONSE:

No corneal reflex ( 5 and 7 nerve )

No jaw reflex ( 9th nerve)

No grimacing to deep pressure on nail bed,supraorbital ridge, or temporo-mandibular

joint ( afferent 5th and efferent 7th )

FACIAL SENSATION AND FACIAL

MOTOR RESPONSE:

No corneal reflex ( 5 and 7 nerve )

No jaw reflex ( 9th nerve)

No grimacing to deep pressure on nail bed,supraorbital ridge, or temporo-mandibular

joint ( afferent 5th and efferent 7th )


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PHARYNGEAL AND TRACHEAL

REFLEXES:

No response after stimulation of the

posterior pharynx

No cough response to tracheobronchialsuctioning

PHARYNGEAL AND TRACHEAL

REFLEXES:

No response after stimulation of the

posterior pharynx

No cough response to tracheobronchialsuctioning


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Common misinterpretationsCommon misinterpretations

Spontaneous movements of limbs (other than pathologicflexion or extension ) LAZARUS SIGN

Respiratory like movements ( shoulder elevation andadduction, back arching, intercostal expansion withoutsignificant tidal volumes)

Sweating, flushing, tachycardia

Normal BP without pharmacologic support or sudden

increase in BP Absence of DI

DTRs, Superficial abdominal reflexes, babinski reflex

Spontaneous movements of limbs (other than pathologicflexion or extension ) LAZARUS SIGN

Respiratory like movements ( shoulder elevation andadduction, back arching, intercostal expansion withoutsignificant tidal volumes)

Sweating, flushing, tachycardia

Normal BP without pharmacologic support or sudden

increase in BP Absence of DI

DTRs, Superficial abdominal reflexes, babinski reflex


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Physicians responsibilityPhysicians responsibility

Notify next of Kin

Notify the person closest to the patient that

the process for determining brain death is

underway

Consent not required but religious or moral

objections should be noted

If family members object to invasiveconfirmatory tests, physicians should obey

the hospital counsel and ethics committee

Notify next of Kin

Notify the person closest to the patient that

the process for determining brain death is

underway

Consent not required but religious or moral

objections should be noted

If family members object to invasiveconfirmatory tests, physicians should obey

the hospital counsel and ethics committee


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Interval observation periodInterval observation period After the first clinical examination

observe the patient for a defined period

of time for clinical manifestations that

are inconsistent with the diagnosis ofbrain death

6 hours reasonable for adults and

children >18 yr of age Longer intervals are advisable in young

children 12HRS

After the first clinical examination

observe the patient for a defined period

of time for clinical manifestations that

are inconsistent with the diagnosis ofbrain death

6 hours reasonable for adults and

children >18 yr of age Longer intervals are advisable in young

children 12HRS


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Repeat clinical assessment of

brain stem reflexes

Repeat clinical assessment of

brain stem reflexes

Repeat full clinical examination

When clinical circumstances prohibit

any of the steps it should be

documented

Repeat full clinical examination

When clinical circumstances prohibit

any of the steps it should be

documented


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Confirmatory testingConfirmatory testing

Full clinical examination including both

assessment of brainstem reflexes and

the apnoea test conclusively performed:No additional testing required

Indications for confirmatory testing:

Skull or cervical spine injuries,Skull or cervical spine injuries, Cardiovascular instabilityCardiovascular instability

Incomplete clinical assessmentIncomplete clinical assessment

LESS THAN 1YEAR CHILDLESS THAN 1YEAR CHILD

Full clinical examination including both

assessment of brainstem reflexes and

the apnoea test conclusively performed:No additional testing required

Indications for confirmatory testing:

Skull or cervical spine injuries,Skull or cervical spine injuries, Cardiovascular instabilityCardiovascular instability

Incomplete clinical assessmentIncomplete clinical assessment

LESS THAN 1YEAR CHILDLESS THAN 1YEAR CHILD


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Confirmatory testsConfirmatory tests

ANGIOGRAPHY:

Absence of intracerebral filling at the level

of the carotid bifurcation or circle of Willis The external carotid circulation is patent,

and filling of the superior sagittal sinus may

be delayed

ELECTROENCEPHALOGRAPHY:

30 min of EEG recording 2MV

SENSITIVITY

Absence of electrical activity

ANGIOGRAPHY:

Absence of intracerebral filling at the level

of the carotid bifurcation or circle of Willis The external carotid circulation is patent,

and filling of the superior sagittal sinus may

be delayed

ELECTROENCEPHALOGRAPHY:

30 min of EEG recording 2MV

SENSITIVITY

Absence of electrical activity


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NUCLEAR BRAIN SCANNING:

Absence of uptake of isotope in brain

parenchyma and or vasculature,depending on isotope and technique used (

hollow skull phenomenon )

BEDSIDE PROCEDURE 15MIN

SOMATOSENSORY EVOKEDPOTENTIALS:

Bilateral absence of N20-P22 response

with median nerve stimulation

NUCLEAR BRAIN SCANNING:

Absence of uptake of isotope in brain

parenchyma and or vasculature,depending on isotope and technique used (

hollow skull phenomenon )

BEDSIDE PROCEDURE 15MIN

SOMATOSENSORY EVOKEDPOTENTIALS:

Bilateral absence of N20-P22 response

with median nerve stimulation


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TRANSCRANIAL DOPPLER

ULTRASONOGRAPHY:

Small systolic peaks in early systole

without diastolic flow, or reverberating flow,

indicating very high vascular resistanceassociated with greatly increased

intracranial pressure

TRANSCRANIAL DOPPLER

ULTRASONOGRAPHY:

Small systolic peaks in early systole

without diastolic flow, or reverberating flow,

indicating very high vascular resistanceassociated with greatly increased

intracranial pressure


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Certification of brain deathCertification of brain death

Can be certified by single physician

TWO PREFERRED

In case of organ transplantationIn case of organ transplantation: NewYork State Law states brain death must

be certified by the physician who

attends the donor at his death and

another physician neither of whom shall

participate in the process of

transplantation

Can be certified by single physician

TWO PREFERRED

In case of organ transplantationIn case of organ transplantation: NewYork State Law states brain death must

be certified by the physician who

attends the donor at his death and

another physician neither of whom shall

participate in the process of

transplantation


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Medical record documentationMedical record documentation

Etiology and irreversibility of coma /

unresponsiveness Absence of motor response to pain

Absence of brainstem reflexes during twoseparate examinations separated by at least 6hours

Absence of respiration with pCO2>60mm Hg Justification for, and result of, confirmatory

tests if used

Etiology and irreversibility of coma /

unresponsiveness Absence of motor response to pain

Absence of brainstem reflexes during twoseparate examinations separated by at least 6hours

Absence of respiration with pCO2>60mm Hg Justification for, and result of, confirmatory

tests if used

2. Brain Death

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