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Declaring Brain Death in Infants and Children. Bert E. Johansson, MD,PhD,FAAP. Brain Death and Organ Donation. Definitions of Death: Cardiorespiratory death: irreversible cessation of circulatory and respiratory function
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Declaring Brain Death in Infants and Children Bert E. Johansson, MD,PhD,FAAP
Brain Death and Organ Donation Definitions of Death: • Cardiorespiratory death:irreversible cessation of circulatory and respiratory function • Whole brain death: irreversible cessation of all functions of the entire brain • Partial brain death (controversial): irreversible cessation of brain functions necessary for personhood
Alternative views of death “Higher brain” or partial brain concepts of death focus on: • loss of cognitive functions • loss of capacity for memory, reasoning, and other higher brain functions • loss of personal identity While many individuals feel that loss of the above capacities make a person “as good as dead,” These views are not universally held and currently cannot be measured. At present we are left with defining death in the PICU by measurable parameters.
Uniform Determination of Death Act 1982 The Uniform Determination of Death Act forms the legal basis for the recognition of brain death in the US. This act states that an individual is dead after: • Irreversible cessation of circulatory and respiratory functions, or • Irreversible cessation of all functions of the entire brain, including the brain stem. Determination of death must be made in accordance with accepted medical standards.
Complicating factors in defining and explaining death • Confusing use of terminology when speaking with families, e.g. “continuing life support” in the face of brain death while awaiting organ donation • Clinical findings may not support irreversible loss of allbrain functions, e.g. lack of diabetes insipidus when all other findings are consistent with brain death • Different and evolving religious definitions of death Orthodox Jewish tradition Islamic tradition Fundamentalist Christian
Diagnosis Of Death By Neurologic Criteria Locally used guidelines are adapted from the President’s Commission, 1981, and the Task Force for the Determination of Brain Death in Children (AAP), 2011:
2011 Guidelines on Brain Death • Determination of brain death in neonates, infants and children relies on a clinical diagnosis • Based on the absence of neurologic function with a known irreversible cause of coma. • Coma and apnea must coexist to diagnose brain death. • Diagnosis should be made by physicians who have evaluated the history and completed the neurologic examinations.
2011 Guidelines on Brain Death • Exclusion of potentially reversible causes of coma, including: • • sedatives and paralyzing drugs • • hypothermia • • metabolic and endocrine disturbances (severe electrolyte or glucose disturbances) • • hypotension • • surgically operable intracranial conditions • • other reversible causes
Clinical Testing 1. Absence of cortical function • Coma; no voluntary movements; no posturing; no seizures; spinal reflexes may persist 2. Absence of brainstem function • No sympathetic or parasympathetic pupil regulation • Absent oculo-cephalic and oculo-vestibular responses • Absent blink response to corneal stimulation • Absent gag response • Absent oculo-cardiac response • No breathing with standardized apnea testing 3. Repeated observations recommended
Plum F, Posner JB. The diagnosis of stupor and coma. 3rd ed. Philadelphia:FA Davis, 1982:104.
2011 Guidelines on Brain Death Prerequisites For Initiating A Brain Death Evaluation a. Hypotension, hypothermia, and metabolic disturbances affect the neurological examination must be corrected prior to examination. b. Sedatives, analgesics, neuromuscular blockers, and anticonvulsant agents should be discontinued for a time based on elimination half-life of the agent. Obtain blood or plasma levels of anticonvulsants with sedative effects.
2011 Guidelines on Brain Death Prerequisites For Initiating A Brain Death Evaluation c. The diagnosis of brain death based on neurologic examination alone can not be made if supratherapeutic or high therapeutic levels of sedative agents are present. Low to mid-therapeutic levels unlikely to affect the exam. d. Assessment of neurologic function may be unreliable immediately following cardiopulmonary resuscitation or acute brain injuries and evaluation should be deferred for 24 to 48 hours or longer.
2011 Guidelines on Brain Death • Number of examinations, examiners and observation periods • Two examinations including apnea testing with each examination separated by an observation period are required. • The examinations should be performed by different attending physicians involved in the care of the child. The apnea test may be performed by the same physician, preferably the attending physician who is managing ventilator care of the child.
2011 Guidelines on Brain Death Number of examinations, examiners and observation periods c. Recommended observation periods: (1) 24 hours for neonates (37 weeks gestation to term infants 30 days of age) (2) 12 hours for infants and children (30 days to 18 years). d. The first examination determines the child has met neurologic examination criteria for brain death. The second examination, performed by a different attending physician, confirms that the child has fulfilled criteria for brain death.
2011 Guidelines on Brain Death • Apnea testing • Apnea testing must be performed safely and requires: • Documentation of an arterial PaCO2 20 mm Hg above the baseline PaCO2 and, • > 60 mm Hg with no respiratory effort during the testing period. • If the apnea test cannot be performed due to a medical contraindication or cannot be completed because of: • hemodynamic instability, • desaturation to 85%, or • an inability to reach a PaCO2 of 60 mm Hg or greater, • an ancillary study should be performed.
2011 Guidelines on Brain Death • Ancillary studies • Ancillary studies (EEG and radionuclide CBF) are not required to establish brain death unless the clinical examination or apnea test cannot be completed • Ancillary studies are not a substitute for the neurologic examination.
2011 Guidelines on Brain Death Ancillary studies • For all age groups, ancillary studies can be used to assist in making the diagnosis of brain death when • Components of the examination or apnea testing cannot be completed, • if there is uncertainty about the results of the neurologic examination; or • if a medication effect may interfere with evaluation of the patient. • reduce the observation period • When an ancillary study is used to reduce the observation period, all aspects of the examination and apnea testing should be completed.
2011 Guidelines on Brain Death Ancillary studies • d. When an ancillary study is used because there are inherent examination limitations, then components of the examination done initially should be completed. • e. If the ancillary study is equivocal, the patient cannot be pronounced dead. • The patient should continue to be observed until brain death can be declared on clinical examination criteria and apnea testing, or a follow-up ancillary study can be performed. • A waiting period of 24 hours is recommended before further cinical reevaluation or repeat ancillary study is performed. • Supportive patient care should continue during this time period.
Confirmatory testing In the US, confirmatory tests are not required under most guidelines if prerequisites are met and testing is not confounded. Example: apnea test unlikely to be valid in patient with cervical spine transection, necessitating alternative testing. Confirmatory tests do not prove brain death in the face of clinical signs that brain death has not occurred.
Types of confirmatory testing • Tests of brain activity • EEG: testing is confounded by the same issues that may confound clinical exam (sedation,hypothermia), is plagued by artifact in the ICU setting, and does not assess brainstem function well • Evoked potentials: not sufficiently validated; highly dependent on technician and interpreters • Tests of blood flow • 4-vessel contrast angiography • radionuclide scintigraphy: less invasive; • transcranial Doppler sonography: reliable in experienced hands only
EEG Recording Exhibiting Electrocerebral Silence Moshe SL, et al, Pediatric Brain Death and Organ/Tissue Retrieval, Kaufman HH ed., 1989 Plenum Publishing Co, New York, p.144
Dynamic Radionuclide Cerebral Angiogram Consistent with Brain Death Goodman J, et al, Pediatric Brain Death and Organ/Tissue Retrieval, Kaufman HH ed., 1989 Plenum Publishing Co, New York, p.144
Abnormal static phase radionuclide cerebral imaging scan, in which no radionuclide material is detected within the cranial vault. The central “hot spot” reflects circulation to the patient’s nose, which serves to confirm the entrance of radionuclide up to the level of the common carotid artery. Schwartz JA, et al, Pediatric Brain Death and Organ/Tissue Retrieval, Kaufman HH ed., 1989 Plenum Publishing Co, New York, p.144
2011 Guidelines on Brain Death Declaration of Death a. Death is declared after confirmation and completion of the second clinical examination and apnea test. b. When ancillary studies are used, documentation of components from the second clinical examination that can be completed must remain consistent with brain death. c. The clinical examination should be carried out by experienced clinicians who are familiar with infants and children, and have specific training in neurocritical care.
Discussing brain death with families • When? The concept should be introduced when the medical team feels that its discussion will improve family’s understanding of the patient’s condition and prognosis. • Who? A team member who has a good rapport with the family, has a full understanding that brain death is no less death than is cardiorespiratory death, and can maintain a continuing supportive role. • Why? It is a generally accepted duty of medical caregivers to disclose truthful information to families that will help them to understand their child’s condition, and to provide guidance to them in their roles as medical decision makers.
The Family Who Refuses The Diagnosis Of Brain Death • Families may be unable to understand or to accept the diagnosis of brain death • Contributing factors • Lack of trust • Mixed messages • Sudden nature of many events leading to brain death
Approach To The Reluctant Family • Patience; consistent messages given in a compassionate manner • Consider involving clergy or others in whom the family has confidence • Consider and respect religious beliefs; some states allow religious beliefs to override local hospital policy