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Explore the historical & legal aspects of brain death, from biology to Indian Law. Learn about the criteria, laws, and practical tips related to brain death testing and verification processes.
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Brain Death ISCCM FOUNDATION DAY
Historical-What is death? • Biology not understood before the Renaissance • Various Descriptions • A state after the end of life • Apnoea, unresponsiveness, immobility • Followed by decay • When ‘life’ or ‘the spirit’ departed from the body • Immense cultural, religious, mystical significance
The biology of death • Understanding possible after Harvey described thecirculation of blood and the pump function of the heart • “…the heart is the principle of life…from which heat and life are dispersed to all parts…” • Death when the heart and circulation stopped Harvey, William. Exercitatio anatomica de motu cordis et sanguinis in animalibus. Francof.,1628English translation (On the motion of the heart and blood in animals) at http://www.fordham.edu/halsall/mod/1628harvey-blood.html
Brain death? The Death of the brain, while the circulation persists. A clinical syndrome • First recognised over 50 years ago • Only possible on ventilatory support • Revealed by intensive Care Medicine • Apnoea, unresponsiveness and other features
The transplantation of human organs act 1994 (THOA) • Bill No. LIX-F of 1992 The Transplantation of human organs bill, 1994 • (As Passed by the Houses of Parliament Rajya Sabha on 5th May, 1993) Lok Sabha on 14th June 1994 Amendments made by the Lok Sabha Agreed to by the Rajya Sabha on 15th June 1994) Assented to on 8-7-1994 Act No. 42 of 1994 • Bill No. LIX-F of 1992 THE TRANSPLANTATION OF HUMAN ORGANS BILL, 1994 --------------- ARRANGEMENT OF CLAUSES ------------
Definition of Deceased Person The Transplantation of Human Organs Act, 1994 (Central Act 42 of 1994),- 'Deceased person' means a person in whom permanent disappearance of all evidence of life occurs, By reason of brain-stem death or In a cardio-pulmonary sense at any time after live birth has taken place. ‘Brain-stem death' means the stage at which all functions of the brain stem have permanently and irreversibly ceased.
Normal Brain Anatomy Cerebral Cortex Reticular Activating System Brain Stem
Brain Stem Midbrain Cranial Nerve III • pupillary function • eye movement
Brain Stem • Pons • Cranial Nerves IV, V, VI • conjugate eye movement • corneal reflex
Brain Stem • Medulla Cranial Nerves IX, X • Pharyngeal (Gag) Reflex • Tracheal (Cough) Reflex • Respiration
Neuronal Injury Neuronal Swelling Decreased Intracranial Blood Flow Mechanism of Brain Stem Death ICP>MAP is incompatible with life Increased Intracranial Pressure
STEP..1 Establish if there is an underlying cause for the patient to be brain dead
Few Possible Causes may progress to- Brain Death Cerebral Anoxia Trauma Cerebral Hemorrhage Subarachnoid Hemorrhage
Always ask yourself- Is there a cause for the patient to be brain dead? • potential cause for brain stem dysfunction? • No obvious cause or if there is any doubt about the cause - be cautious in diagnosing brain death • Make sure there are no confounders that mimic brain death
STEP..2 Look for confounders before proceeding for brain death verification
Rule out the following and aim for near normal values- PRECONDITIONS • Severe hypothermia - core temperature of ≤32°C • Severe hypotension (With or Without Vasopressors) - systolic blood pressure <100 mmHg • Drugs - alcohol, poisoning, recent use of sedation or neuromuscular blocking agents • Medical conditions - severe electrolyte abnormalities, hypoglycemia, acid–base abnormalities
Practical Tips • Insist on core temperature measurement • Always look in history for, drugs, overdose, sedation, etc • If available use a Peripheral Nerve Stimulator for – TOF response • Have most recent values for Sodium and potassium available • Insist on ABG at start of clinical testing with 100% O2 Pre-oxygenation
Brain Death Criteria • Brain death is established by documentation of • Irreversible coma • Irreversible loss of brain stem reflexes • Cessation of respiratory centre function • or • 4. Demonstration of cessation of intracranial blood flow
Brain Death Criteria • Brain death is established by documentation of • Irreversible coma • Irreversible loss of brain stem reflexes • Cessation of respiratory centre function • or • 4. Demonstration of cessation of intracranial blood flow (NOT a Part of THOA Act)
Who Does the Testing and When • Testing can be done after 4- 6 hours of NO recordable brain Stem Signs by bed side Nurse and Doctors, provided pre conditions are met • Testing is done by 2 Doctors- at and interval of 6 hours apart. The doctors can be Neurologist, Intensivist, Neurosurgeon or an equally qualified doctor who is certified to be on the hospital brain death panel. • 2 More persons observe the process and sign of the final document- Primary Physician and Hospital Administrator
Neurological examination for diagnosing Brain Death • This consists of three essential steps: • Documentation of coma • Documentation of the absence of brainstem reflexes • Documentation of apnea (apnea test) C C C C
Practical Tips • Start Pre- Oxygenation with 100% Oxygen • Obtain a ABG- Will give you pH, Oxygen, Carbon Di Oxide, Electrolytes, Blood Glucose
Documentation of coma • Absence of motor response to a Central Deep painful stimulus • Beware of local spinal reflexes causing spontaneous or stimulus-related motor movements
Response to painful stimuli Within cranial nerve distribution
Documentation of the absence of brainstem reflexes • Brainstem reflexes are lost in a rostral-to-caudal direction • Reflexes in medulla oblongata are the last to cease • Tests documented are • Absent pupillary reflex • Absent oculocephalic movements (doll’s eye reflex)- • Absent oculovestibular reflex (cold calorie test) • Absent corneal reflex • Absent cough reflex
Documentation of apnea (apnea test) • Done only after • Documentation of coma • Documentation of absence of brain stem reflexes
Documentation of apnea (apnea test) • Steps • Pre-oxygenate patient with 100% oxygen for 15 minutes • Obtain an ABG • Disconnect patient from mechanical ventilation • Continue to oxygenate through a catheter placed in the trachea – Aim for saturation above 95%- use 4-6 L/min of O2 • ABG is repeated within about 8–10 minutes • Increase in PaCO2 (above 60mmHg or 20mmHg from base line) and lack of respiration documented (use EtCO2) if available
Practical Tips • Pre-oxygenation with 100 % Oxygen for at least 15min. • Give adequate volume and Vasopressors to keep MAP ~ 70mmHg • CO2 rises by around 3mmHG/min of apnea, so be prepared to test at least for 8- 10min
Brain Death Confirmed • Once the 2 specialist complete the test the time of death is confirmed as the end of second examination time
Observations compatible and incompatible with brain death • Compatible: • Spinal reflexes • Sweating, blushing, tachycardia • Normotension without pharmacologic support • Absence of diabetes insipidus • Incompatible: • Decerebrate or decorticate posturing • Extensor or flexor motor responses to painful stimuli • Seizures
Confirmatory Tests- Not required in India and NO mention in THOA act • These tests are optional in adults • Recommended in children younger than 1 year • Certain countries mandate these tests by law to confirm brain death • The tests are • Cerebral angiography (conventional or CT) • Cerebral scintigraphy • Electroencephalography (EEG)- NOT RECOMMENDED • Transcranial Doppler (TCD) ultrasound- NOT RECOMMENDED
Radiographic Confirmation of Death • Testing is not complete or possible – ie facial fractures, swollen eyes etc • Or C spine fractures • Apnea test becomes a challenge