Diagnosis of Brain Death

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Diagnosis of Brain Death

• Kenneth E. Wood, DO
• Professor of Medicine and Anesthesiology
• Senior Director of Medical Affairs
• Director,Critical Care Medicine and Respiratory
  Care
• The Trauma and Life Support Center
• University of Wisconsin Hospital and Clinics

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Certification of Death

• As Mayor of Munchkin City
• In the county of the Land of Oz,
• I welcome you most regally.
• But weve got to verify it legally.
• To seeif she
• Is morally, ethicly, spiritually
• physically, positively, absolutely, undeniably
  and reliably DEAD!
• As the corner, I must aver,
• I thoroughly examined her,
• And shes not only MERELY dead,
• Shes really, most SINCERELY dead.
• The Wicked Old Witch.is dead !

Wizard of Oz
Shanner Neurology 2004621683-86
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Certification of Death

• Legally
• Morally
• Ethically
• Spiritually
• Physically
• Positively, Absolutely, Undeniably and Reliably,
  really, most Sincerely Dead

Wizard of Oz
Shanner Neurology 2004621683-86
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If it becomes at all doubtful, let me know, I
will be just inside
920 PM
Captain Edward Smith to second officer
Lightoller who then signed over to Murdoch at
1000 PM
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1140 PM
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Brain Death Historical Perspective
Patients die from respiratory and not from
cardiac failure as it is often supposedthe
respiration suddenly ceases, the heart continues
to beatsuch was the end of practically all cases
of pathologic intracranial tension
Horsley Quart J Med July 1894
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Brain Death Historical Perspective
some cases of cerebral disease in which the
function of respiration entirely ceases for some
hours before that of the circulationwith
respiratory cessation, death had practically
begun
Duckworth Edinburgh Med J 1898 3145-152
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Brain Death Historical Perspective
in death from a fatal increase in intracranial
tension, the arrest of respiration precedes that
of the heartprompt surgical relief, with a wide
opening of the calvarium, may save life even in
desperate cases with a pronounced medullary
involvement
Cushing Am J Med Sci 1902124375-400
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Lessons and Questions from the Guillotine
once the head has been severed from the neck,
the heart continues to beat for up to an hour
Dujardin Bulletin de la Societe de Medicine
Legale de France 1870549-74
The head fell on the severed surface of the
neck, the eyelids/lips worked in irregular
rhythmic contractions for 5 or 6 secondsI called
in a strong voice Languillethe eyelids lifted
up slowlyLanguilles eyes very definitely fixed
on mineundeniably living eyes looking at meI
called out again, the eyelids lifted and
undeniably living eyes focused themselves on
mine. The whole thing lasted 25-30 seconds.
Guillotine Death of Languille reported by Dr.
Beaurieux 1905
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Anatomic vs. Physiologic Decapitation
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Pathophysiology of Brain Death Complicating
Features

• Variability in definitions of brain death
• Disparity in certification vs tissue death
• No human model available
• Concomitant injuries
• Rate of progression leading to brainstem dysfxn
• Treatment of brain injury causes physiologic
  changes independent of brain injury

Power Anesth Int Care 1995 2326-36
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Physiologic Changes Preceding Brain Death

• Arrhythmias 27
• Hypothermia 4
• Transfusions 63
• Pulm Edema 19
• Hypoxia 11
• Acidosis 11
• Seizures 10

• Significant and devastating physiologic changes
  prior to diagnosis of brain death
• Process ? certification 17-22 hrs
• ? Elapsed time ? complications - 8 loss
  potential donors
• Cardiovascular instability 80
• Diabetes Insipidus 53-93
• DIC 28
• CPR 25

Nygaard Trauma 1990 30728-732
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A
B
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A
B
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Medical Diagnosis of Death Persistent
Fundamental Questions Residence of Vital
Principle of Life
Centralist
Decentralist

Greeks ? Heart Judeo-Christian ?
Breath Maimonides ? Brain
Throughout all organs tissues or cells

• Exclusion of a falsely positive diagnosis of
  death with maximum certainty
• (apparent death ? confounding factors)

Powner Lancet 1996 3481219-23
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Controversies in Brain Death

• Whole brain death criteria
• Brainstem death
• Cerebral or Neocortical death
• (loss of higher cerebral function)

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Variability Among Hospital Policies for
Determining Brain Death
Powner CCM 2004321284-1288
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Variability in Determining Brain Death

• Exclusionary/Precautionary Conditions
• 12 NOT identified
• 88 hypothermia
• 79 used 32.2 C
• 20 did not specify lower limit

Powner CCM 2004 32 1284-1288
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Variability in Determining Brain Death

• Physical Exam
• All policies only physicians
• 46 required two physicians
• 44 required only 1 physician
• 11 did not specify number of physicians
• 38 required knowledgeable physicians
• 27 required attending physicians
• 29 clear method for testing cranial nerves
• 96 required apnea test
• 52 final PaCO2 gt 60 mmkg
• 12 final PaCO2 40-59 mmkg
• 37 did not stipulate PaCO2
• 60 recommended serial testing

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Variability in Determining Brain Death

• Confirmatory Tests
• 8 required a confirmatory study
• 18 no mention of confirmatory study beyond
  physical exam
• 74 recommended a supplemental test or considered
  it optional

• 73 EEG
• 59 Flow Scan
• 48 Angiogram

• 13 Transcranial Doppler
• 15 Evoked Potential
• 3 ICP gt MAP
• 1 MRI

Powner CCM 2004 32 1284-1288
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Variability in Brain Death Guidelines
Hornby Can J Anesth 2006 53 613-619
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Variability in Brain Death Guidelines
Apnea Testing
Supplementary Tests
Confounding Factors
Hornby Can J Anes 200653613-619
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Brain Death and Organ RetrievalHealth
Professionals Knowledge and Concepts

• 63 knew irreversible loss of all brain function
  was required for brain death declaration
• 69 correctly identified patient with
  irreversible loss of all brain function
• 35 knew whole brain criterion AND correctly
  applied to identify patient status
• 38 identified irreversible cortical loss as
  death (morally permissible to retrieve
  organs-36)
• 23 did not favor required request laws (MDs)

Younger JAMA 1989 2612205-2210
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NeurologistsBrain Death and Apnea Testing

• 14 adhered to rigorous approach
• 75 assessed apnea by vent disconnection 3 min.
• 75 did not provide 100 FiO2
• 75 did not check PCO2 levels
• 9 observed for absence of triggering vent

Earnest Neurology 1986 36542-544
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Wang Neurosurg 2002 51 731-736
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Le Coma Depasse (1959)

• Irreversible or Irretrievable coma
• such a coma was not only a revelation, but also
  a price one has to pay from the skills acquired
  in resuscitation
• Detailed clinical and EEG findings
• Ethical issues

Mollaret Revue Neurologique 1959 1013-15
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EEG Determination of Death (1963)

• Absence of spontaneous respiration for 30 minutes
• No tendon reflexes of any type
• No pupillary reflexes, dilated
• Eyeball pressure must not change heart rate
• Flat line EEG all leads for 30 minutes

Schwab Electroencephalogr Clin Neurophysiol
1963 15147
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Organ Transplantation Practical Possibilities
Brain Death Criteria (1966)

• Complete bilateral mydriasis
• Complete absence of reflexes in response to pain
• Complete absence of respiration for 5 minutes
• Falling blood pressure necessitating increasing
  doses of vasopressors
• Flat EEG for several hours

Alexandre Ciba Symposium 1966 5477
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Organ Transplantation Practical Possibilities
Brain Death Criteria (1966)

• Consultation 3 physicians Hospital Chief
• Written, signed report ? hospital/authorities
• Proof of existence of irreversible lesions
  inconsistent with survival
• Loss of all reflexes
• Fixed dilated pupils
• Flat EEG or demonstration of observed lesion
• Complete support of respiratory/circulation

Revillard Ciba Symposium 1966 5477
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Brain Death and Transplantation

• I doubt if any members of our transplant team
  could accept a person as being dead as long as
  there was a heart beat
• Starzl
• Although Alexandres criteria are medically
  persuasive according to traditional definitions
  of death, he is in fact removing kidneys from
  live donors. I feel that if a patient has a
  heart beat, he cannot be regarded as a cadaver
• Calue

Ciba Symposium 1966 5477
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Newsweek 1967 7087
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Brain Death Criteria (1967)

• You are dead when your doctor says you are.
  Death comes when the physician has done
  everything to save the patients life and comes to
  the point where he feels the patient cant live.
  Once a man makes up his mind to stop that
  respirator or cardiac pacemaker, from that
  minute, the patient is dead.

Carl Wasmuth, MD President, American College of
Legal Medicine (1967)
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JAMA 1968 205337-340
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Harvard Ad Hoc Committee Definition of Brain
Death (1968)

• Unreceptivity and unresponsitivity
• No movements or breathing
• No reflexes
• Flat EEG
• All of above repeated at least 24 hours with no
  change
• Exclusion

Hypothermia (? 90?F or 32.2? C)
CNS Depressants
JAMA 1968 205337-340
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Brain Death Criteria Modification

• Specific instances ? no need to await development
  of criteria of irreversible coma/24 check
• Committee unanimous EEG NOT essential but
  supporting
• Clinical course of irreversible coma (15)
• All died 9/15 lt 24 hours
• Questioned 24 hour period

Beecher NEJM 1969 2811070-71.
Beecher Neurology 1970 20459-62.
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Minnesota Brain Death Criteria (1971)

• No spontaneous movement
• No spontaneous respiration for 4 minutes
• Absent brainstem reflexes
• pupillary - ocular vestibulo
• corneal - oculocephalic
• ciliospinal - gag
• - tonic neck reflex
• All finding unchanged for 12 hours
• Brain death only if path process deemed
  irreparable

Dolls Eyes
calorics
Mohandas J Neurosurg 1971 35211-18
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United Kingdom Statement (1976)
No depressant drugs

• Patient deeply comatose
• Spontaneous respiration inadequate/ceased
• exclude relaxants, hypnotics, narcotics
• Diagnosis established ? no doubt condition is due
  to irremediable structural brain damage
• Tests to confirm brain death
• pupils fixed/non-reactive - no motor CN
• No corneal reflex - no gag/cough
• Absent vestibulo-ocular reflex - no resp
  movements
• (pCO2 50mmHg)

No hypothermia
No metabolic/endo issues
BMJ 1976 21187-88
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United Kingdom Statement 1976 Considerations

• Repetition of testing
• Interval depends upon 1 ? condition and clinical
  course of disease up to 24 hours
• Integrity of spinal reflexes
• Confirmatory investigations
• EEG NOT necessary
• Body temp ?35 ?C
• Specialists opinion/status of MDs concerned
• Consultation and one other MD
• Deputy (5 years) and one other MD

BMJ 1976 21187-88
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US Collaborative Study Criteria (1977)Appraisal
of Criteria of Cerebral Death

• Appropriate examinations/therapeutic procedures
  performed
• Cerebral unresponsivity, apnea, dilated pupils,
  absent cephalic reflexes, EEG silence for 30
  minutes at least 6 hours after onset
• Inability to test or standard met imprecisely
  confirmatory test to demonstrate absence of
  cerebral blood flow

JAMA 1977 237982-86
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Presidents Commission Ethical ProblemsUniform
Determination of Death Act (1981)

• An individual who has sustained either
• Irreversible cessation of circulatory and
  respiratory functions
• OR
• Irreversible cessation of all functions of the
  entire brain, including the brainstem, is dead
• A determination of death must be made in
  accordance with accepted standards

JAMA 1981 2462184-86
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Presidents Commission Ethical Problems
(1981)Guidelines for Determination of Death

• Cessation
• Coma with unreceptivity and unresponsivity
• Absent brain stem function
• Apnea test PaCO2 gt 60 mmHg
• Absence of decorticate posturing/seizures
• Irreversibility
• Cause established and sufficient
• Reversible conditions excluded
• Persists for appropriate period
• Confirmatory studies
• Cannot adequately test
• Sufficient cause not established
• Shorten observation time

6 hrs exam/confirm
12 hrs exam
24 hrs exam
JAMA 1981 2462184-86
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Royal College Brain Stem Death (1995)

• No doubt condition due to irremediable brain
  damage
• Patient is deeply comatose
• No suspicion state due to depressant drugs
• Primary hypothermia excluded
• Potentially reversible metabolic and endocrine
  disturbances excluded
• Spontaneous respiration has become inadequate or
  ceased requiring mechanical ventilation

J Royal College Physicians 1995 29381-82
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Diagnostic Approach to Brain Death (AAN)
Coma
No severe electrolyte acid base disturbances
No hypothermia

Cause of coma evidence clinical?Neuroimage?CSF

• No drugs
• Intoxication
• Sedatives
• Relaxants
• Poisoning

No endocrine crisis

• Clinical Neuro Exam
• Absent motor response
• Absent brainstem function
• Apnea test PaCO2 ? 60 mmHg

Clinical Diagnosis Brain Death
-

Disconnect vent
Procurement
Donor?
Wijdicks Neurology 1995 451003-11
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Day 1
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Day 2
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Day 3
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Declaration of Brain Death

• Cessation of Brain Function
• cerebral functions absent
• brainstem functions absent
• Irreversible Loss of Brain Function
• etiology known
• cause sufficient to account for loss of
  cerebral-brainstem function
• no possibility for recovery-reversible causes of
  cessation excluded
• cessation of cerebral/brainstem function persists
  for an appropriate period

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Declaration of Brain DeathClinical Correlation

• Documentation of loss of consciousness
• No motor response to stimuli
• No brainstem reflexes
• Apnea
• Normal CT/CSF-question clinical diagnosis
• Coma of unknown origin-observation/confirmatory

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Clinical DX of Brain DeathConfounding Variables

• Hypothermia lt 32?C
• Drugs
• paralytics
• barbiturates
• sedatives/hypnotics
• alcohol intoxication
• Acute metabolic or endocrine derangements
• electrolyte, acid-base derangements
• uremia
• hepatic coma
• hypoglycemia
• hypothyroid

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States Resembling Brain Death

• Hypothermia
• Diagnosis of brain death requires core temp gt 32?
• 28 ? - 32 ? pupillary dilation sluggish light
• ? 28 ? loss of brain stem reflexes
• Poisoning
• Barbiturates/tricyclic antidepressants
• Pupillary response
• Barbiturates
• Antihistamines
• Tricyclic anti-depressants

Mydriasis (8-9mm) Mid-position (6-7 mm)

• Amphetamines
• Cocaine
• Phenylephrine

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States Resembling Brain Death General Approach to
Acute Poisonings

• Administer antidotes
• Narcotics ? naloxone
• Benzodiazepines ? flumazenil
• Carbon monoxide ? oxygen
• Carbon disulfide, cyanide, hydrogen sulfide ?
  amyl nitrite
• Declare brain death if screening test with traces
  of drug below therapeutic level
• Inability to quantify drug/poison ? observe for
  4X half life
• Unknown but high suspicion ? 48 hrs if no ? ?
  confirmatory study

Wijdicks Brain Death 2001
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Drugs Confounding Neuro Exam
Drug
Therapeutic Range
Half-life (h)
Wijdicks Brain Death 2001
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Early Diagnosis Brain Death CNS Depressants
Barbiturates Opiates Benzodiazepines
Clinical/EEG Criteria (36)
Metabolic Clearance
Transcranial Doppler
99M Tc-HMPAO
Presumptive Definitive Dx Decrease delay
34 hours
17 hours
5 hours
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85

• Barbiturates ? EEG silence ? 50 ? cerebral
  blood flow and metabolism

Heinemeyer Clin Pharmacokinet 1987 131
Lopez-Navidad Transplantation 2000 70131-35
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Topsy Turvydom in Brain Death Determination

• Replacement of a comprehensive neurological exam
  by a technical study in patients suspected of
  brain death should be considered unacceptable
• Elevate the status of a confirmatory study to a
  diagnostic test
• The clinical diagnosis of brain death is a
  sacrosanct principle whatever a sophisticated
  technical test may show

Wijdicks Transplantation 2001 72355-57
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States Resembling Brain Death
Neurologic Disorders

• Locked-in Syndrome
• Akinetic mutism, persistent vegetative state
• Non-convulsive status epilepticus
• Endocrine crisis
• Acid-base disturbances
• Severe electrolyte disturbances

Central
Peripheral
Herpes Encephalitis CPM Head Injury Glioma
Guillain-Barre Synd Organophosphate Neuromuscular
blockers Advanced ALS
Basilar artery Demyelinating Pontine
Abscess Pontine Hemorrhage
Metabolic Encephalopathy

• Uremic enceph
• Hepatic enceph

Wijdicks Brain Death 2001
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Brain Death-Associated Reflexes and Automatisms

• Ivan 1973 (52)1
• 35 muscle stretch reflex
• 60 plantar flexor responses
• 35 plantar withdrawal
• 75 abdominal reflexes
• Jorgensen 1973 Spinal Man (63)2
• 79 withdrawal response lower limbs
• 49 muscle stretch reflexes upper
• 33 muscle stretch reflexes lower
• 33 cutaneous stimulation extension and
  pronation
• Saposnik 2001 (38)3
• 39 with spontaneous or reflex movement first 24
  hrs.

1. Ivan Neurology 197323650-652 2. Jorgensen
Acta Neurochir 197328239-273 3. Saposnik J
Neurol 2001 8 209-213
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Brain Death Associated Reflexes
Jain Neurocrit Care 20053122-126
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Brain Death-Associated Reflexes and Automatisms

• Pathophysiology spinal cord source
• Present if ischemic lesion above CI-4
• Central generators for specific motor patterns
• Corticospinal and rubrospinal in lateral
  funiculus distal limbs
• Vestibulospinal and retculospinal modulate tone
  and posture
• Supraspinal disconnect ? excitabilty
• Phylogenetically old motor patterns set free
  from phylogenetically young brain stem
• Differentiate Polysegmental reflexes/automatisms
  from voluntary or involuntary brain stem
• Depict localization PSRP/PSAP
• Temporal relationship

1. Jain Neuro Crit Care 20053122-126 2.
Spittler Europ J Neuro 20007315-312
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Diversity of Spinal Reflexes in Brain Death
Spittler Europ J Neuro 20007315-321
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Clinical DX of Brain Death

• Coma/Unresponsiveness
• Absence of brainstem reflexes
• Apnea

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CLINICAL DX OF BRAIN DEATHCOMA/UNRESPONSIVENESS

• Motor response of limbs
• response to painful stimuli absent
• Complicating features
• Lazarus sign
• neuromuscular blockers - nerve
• stimulator with response to train of 4

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Clinical DX of Brain DeathAbsence of Brainstem
Reflexes

• 1. Pupillary Response
• Testing
• no response to bright light
• pupils in mid-position (4-6 mm)
• Complicating features
• drugs influence size but light response intact
• atropine without influence on pupil response
• NM blockers do not influence pupil size
• trauma/ocular installation of drugs can cause
• abnormal size and non-reactivity

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Clinical DX of Brain DeathAbsence of Brainstem
Reflexes

• 2. Ocular Movements
• Testing
• Oculocephalic reflex (Dolls eyes)
• Cold water calorics
• Absent motion
• Complicating features
• Head or C-spine trauma
• Drugs ? or abolish response
• Sedatives
• Aminoglycosides
• Tricyclic antidepressants
• Anticholinergics
• Antiepileptic agents
• Chemotherapeutic agents

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Clinical DX of Brain DeathAbsence of Brainstem
Reflexes

• 3. Facial Sensation/Motor Response
• Testing
• Corneal
• Facial
• 4. Pharyngeal and Tracheal Reflexes
• Testing
• Gag reflex
• Cough/response/bronchial suctioning

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Clinical DX of Brain DeathApnea Testing

• Goals
• Document lack of spontaneous ventilatory activity
  during sufficient hypercapnea
• Maintain adequate perfusion/oxygenation
• Prerequisites
• Preoxygenate
• Core temp gt36.5?C
• Systolic BP gt90
• Euvolemia
• Eucapnia
• Normoxemia

?
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Clinical DX of Brain DeathApnea Testing

• Testing
• Preoxygenate
• 6-10L/minute E.T. cannula
• Apply pulse oximetry
• Disconnect patient from ventilator
• Assessment
• Absence of respiratory movements
• CO2 threshold
• 60 mmHg or 20 mmHg gt baseline
• 3-6 mmHg/minute ? 8 minutes
• CO2 retentive disease ? confirmatory

Visual inspection
Skin monitors
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Apnea Testing (AAN)
Disconnect from ventilator
6 L/min 100 O2 carina
Observe 8 minutes for respiratory movements
No
Apnea
Repeat test
Yes
? BP, arrhythmias, ? sats
No
Yes
PCO2 ? 60
PCO2 lt 60
PCO2 ? 60
PCO2 lt 60
Clinical DX Brain Death
Repeat (10 minutes)
Clinical DX Brain Death
Confirmatory study
Wijdicks Neurology 1995 451003-11
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Complications Apnea Test (145) Predisposing
factors
Hypotension ( ? 15) Ventricular arrhythmia
Complications
Yes
No
Variable
Complications
Goudreau Neurology 2000 551045-48
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Complications Apnea Test Predisposing Factors
Apnea Tests (145)
Unfavorable conditions (70) 48
Favorable conditions (75) 52
Non-complicated (43) 61
Non-complicated (64) 85
Complicated (27) 39
Complicated (11) 15
Pre-oxygenation is crucial to minimize
complications

• Hypotension 24
• Arrhythmia 1

Goudreau Neurology 2000 551045-48
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Brain Death with Vent ? Asystole
Pallis ABC of Brain Stem Death 1996
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Brainstem Death ? Flat EEG
59 Patients with known structural intracranial
lesions
216
192
120
24
96
72
48
144
168
Pallis ABC of Brain Stem Death 1996
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Brain Dead Clinical Dx on Vent
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Brain Dead Clinical Dx on Vent continuted
Pallis ABC of Brain Death 1996
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Confirmatory Studies

• A confirmatory study is not mandatory but is
  needed for patients in whom specific components
  of clinical testing cannot be reliably evaluated.

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Confirmatory Studies 18th Century

• Tests for sensibility
• Respiration ? mirror, soap bubbles, feather,
  candle to nose or submerge to detect bubbles
• Liquid container on abdomen ? motion

• scalding
• trumpeting

• cauterization
• incisions

• mustard nose
• sharp under nail

Powner Lancet 1996 3481219-23
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Confirmatory Studies 18th Century

• Fellets test-venous pressure no refill
• Monteverdes sign-subq ammonia (-) inflammation
• Balfours test-needles with flags ? heart ?
  contraction
• Claquets test-needles in biceps ? rust
• Foubers test-cut intercostal ? feel heart
• Magnuss sign-ligature finger ? (-) red/blue
• Ripaults sign-pressure eye ? permanent distortion
• Bouchet-cardiac auscultation
• X-ray fluoro ? search for organ movement

Powner Lancet 1996 3481219-23
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Confirmatory Tests

• Cerebral angiography
• EEG
• Transcranial Doppler
• Nuclear imaging

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Confirmatory Studies (flow)

• Conventional 4 vessel angiography
• Intracerebral filling absent, external carotid
  patent, delayed filling superior longitudinal
  sinus
• Nephrotoxicity, possibly ? acceptance rate in
  organ recipients
• Isotope angiography Technetium 99m albumin
• Intracranial activity absent, delayed filling
  sagittal and transverse sinuses
• Posterior circulation not visualized

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Confirmatory Studies (Flow)

• 99m Tc-HMPAO Scan
• Absence of uptake brain parenchyma
• Immediate injection, high cost
• Sensitivity 94 specificity 100
• Spiral CT scan
• Magnetic Resonance Imaging
• Transcranial Doppler Sonography

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Confirmatory Studies (Function)

• Electroencephalography (EEG)
• 16-18 channel for 30 minutes
• Electrical activity absent above 2?V at
  sensitivity of 2?V /mm with filter setting at 0.1
  or 0.3 s and 70Hz
• Lack of reactivity to intensive somatosensory or
  audiovisual stimuli
• Artifacts sensitivity/specificity 90
• Clinical criteria for brain death ? 20 of 56
  patients with residual activity lasting up to 168
  hours

Buchner Eur Neurol 1990 30138-41
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Confirmatory Studies (function)Evoked Potentials
Brain Stem Auditory
Somatosensory

• Wave I auditory nerve
• Waves II, III cochlear, superior olivary
  complex
• Waves IV , V upper pons
• Absence of II-V ? Brainstem Dysfxn
• Does not measure medulla, correlate with severity

• C2
• Centroparietal
• Stimulation median nerve
• Cortical wave N2O absent

Poor Predictive Value
120
Clinical Observations Compatible With a Diagnosis
of Brain Death

• spinal cord responses
• muscle stretch reflexes
• superficial abdominal reflexes
• Babinski reflexes
• respiratory like movements
• profuse sweating
• blushing
• hemodynamic instability

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Diagnosis of Brain Death Recommendations
Exam Interval
Confirmatory Study
Age
Wijdicks NEJM 2001 3441215-21
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Rapid Brain Death Determination

• Pre-RBD
  Protocol Post RBD Protocol
• Potential Donors 141
  16
• Medical failure rate 13
  0
• Other unsuitability 7
  0
• Eligible donors 113
  14
• Family refusal 56
  29
• Consent 44
  71
• Organ/eligible donor 1.8 ?0.2
  3.4 ?0.6
• Time 12.0 hrs.
  3.4 hrs.
• Charges 16,645
  6,125

Jenkins World J Surg 1999 23644-649
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