The diagnosis of brain death is defined as "death based on the absence of all neurologic function." Families who have had a loved one declared brain dead may have questions about what the term really means. Show
What does "brain death" mean?Brain death is a legal definition of death. It is the complete stopping of all brain function and cannot be reversed. It means that, because of extreme and serious trauma or injury to the brain, the body's blood supply to the brain is blocked, and the brain dies. Brain death is death. It is permanent. How is it decided that an individual is brain dead?A doctor will do tests to make a diagnosis of brain death. These tests are based on sound and legally accepted medical guidelines. Tests include a clinical examination to show that an individual has no brain reflexes and cannot breathe on his or her own. In some situations, other tests may be needed. You can ask your doctor to explain or show you how brain death was determined for your loved one. Possibly, an individual may show spinal activity or reflexes such as twitching or muscle contractions. Spinal reflexes are caused by electrical impulses that remain in the spinal column. These reflexes may happen even though the brain is dead. What happens to an individual while these tests are being done?The individual is placed on a machine that breathes for him or her, called a ventilator. This machine is needed because the brain can no longer send signals telling the body to breathe. Special medications to help maintain blood pressure and other body functions may also be given. During the brain death testing, the ventilator and medications continue but they do not affect the results of the testing. Are there drugs that can stop the brain from working and give a false diagnosis?Certain drugs can mask brain function, such as muscle relaxants and sedatives. Testing can only be done when the individual has low levels of these drugs in the body. It may be necessary to wait for these levels to go down. The doctor can then accurately measure brain activity. Sometimes, other tests are done to confirm brain death if certain drugs are present in the body. If brain death is confirmed, why does an individual's heart continue beating?As long as the heart has oxygen, it can continue to work. The ventilator provides enough oxygen to keep the heart beating for several hours. Without this artificial help, the heart would stop beating. Is it possible that an individual is in a coma?No. A patient in a coma continues to have brain activity and function. When brain death occurs, all brain function ceases and there is no chance of recovery. Is there anything else that can be done?Before brain death is confirmed, everything possible to save an individual's life is done. After the diagnosis of brain death is made there is no chance of recovery. What happens when an individual is declared brain dead?Once the diagnosis of brain death is made, an individual is pronounced legally dead. This is the time that should appear on the death certificate. The time of death is not the time when the ventilator is removed. Does an individual feel any pain or suffer after brain death is declared?No. When someone is dead, there is no feeling of pain or suffering. After brain death is declared, what happens next?A health care professional will talk with you and your family about certain decisions that need to be made at this time. Among those decisions could be removing the ventilator and the possibility of organ and/or tissue donation. Remember, the individual is already legally dead and removing the ventilator does not cause death. See also in this A-Z guide: Author information Copyright and License information Disclaimer Copyright © Indian Journal of Critical Care Medicine This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Physicians, health care workers, members of the clergy, and laypeople throughout the world have accepted fully that a person is dead when his or her brain is dead. Although the widespread use of mechanical ventilators and other advanced critical care services have transformed the course of terminal neurologic disorders. Vital functions can now be maintained artificially for a long period of time after the brain has ceased to function. There is a need to diagnose brain death with utmost accuracy and urgency because of an increased awareness amongst the masses for an early diagnosis of brain death and the requirements of organ retrieval for transplantation. Physicians need not be, or consult with, a neurologist or neurosurgeon in order to determine brain death. The purpose of this review article is to provide health care providers in India with requirements for determining brain death, increase knowledge amongst health care practitioners about the clinical evaluation of brain death, and reduce the potential for variations in brain death determination policies and practices amongst facilities and practitioners. Process for brain death certification has been discussed under the following: 1. Identification of history or physical examination findings that provide a clear etiology of brain dysfunction. 2. Exclusion of any condition that might confound the subsequent examination of cortical or brain stem function. 3. Performance of a complete neurological examination including the standard apnea test and 10 minute apnea test. 4. Assessment of brainstem reflexes. 5. Clinical observations compatible with the diagnosis of brain death. 6. Responsibilities of physicians. 7. Notify next of kin. 8. Interval observation period. 9. Repeat clinical assessment of brain stem reflexes. 10. Confirmatory testing as indicated. 11. Certification and brain death documentation. Keywords: Apnoea test, brain stem function, brain stem reflexes, confounding and compatible conditions In the practice of critical care, ‘the care of a severely brain injured patient ’ is one of the toughest challenges for a critical care physician. Initial therapy provided for patients with severe brain injury or insult, is directed towards preservation and restoration of neuronal function. When this primary treatment is unsuccessful and the patient's condition evolves to brain death, the critical care physician has the responsibility to diagnose brain death with certainty and to offer the patient's family the opportunity to donate organs and / or tissues. There is a clear difference between severe brain damage and brain death. The physician must understand this difference, as brain death means that life support is futile, and brain death is the principal prerequisite for the donation of organs for transplantation. This review focuses on the clinical determination of brain death in adults and children, including the potential confounding factors, and provides an overview of valid confirmatory tests Historically death was defined by the presence of putrefaction or decapitation, failure to respond to painful stimuli, or the apparent loss of observable cardio respiratory action. The widespread use of mechanical ventilators that prevent respiratory arrest has transformed the course of terminal neurologic disorders. Vital functions can now be maintained artificially after the brain has ceased to function. In 1968, an ad hoc committee at Harvard Medical School reexamined the definition of brain death and defined irreversible coma, or brain death, as unresponsiveness and lack of receptivity, the absence of movement and breathing, the absence of brain-stem reflexes, and coma whose cause has been identified. Brain death is defined as the irreversible loss of all functions of the brain, including the brainstem. The three essential findings in brain death are coma, absence of brainstem reflexes, and apnoea. An evaluation for brain death should be considered in patients who have suffered a massive, irreversible brain injury of identifiable cause. A patient determined to be brain dead is legally and clinically dead. The diagnosis of brain death is primarily clinical. No other tests are required if the full clinical examination, including each of two assessments of brain stem reflexes and a single apnoea test, are conclusively performed.
After determining that the patient meets the above prerequisites, the physician should conduct the apnoea test as follows:
Immediately draw an arterial blood sample and analyze arterial blood gas.
Assessment of brainstem reflexes
The following manifestations are occasionally seen and should not be misinterpreted as evidence for brainstem function:
The diagnosis of brain death is primarily clinical. No other tests are required if the full clinical examination, including each of two assessments of brain stem reflexes and a single apnoea test, is conclusively performed. In the absence of either complete clinical findings consistent with brain death, or confirmatory tests demonstrating brain death, brain death cannot be diagnosed and certified. These guidelines apply to patients one year of age or older. The facility must make diligent efforts to notify the person closest to the patient that the process for determining brain death is underway. Consent need not be obtained but requests for reasonable accommodation based on religious or moral objections should be noted and referred to appropriate hospital staff. Where family members object to invasive confirmatory tests, physicians should rely on the guidance of hospital counsel and the ethics committee. After the first clinical exam, the patient should be observed for a defined period of time for clinical manifestations that are inconsistent with the diagnosis of brain death. Most experts agree that a 6 hour observation period is sufficient and reasonable in adults and children over the age of 1 year. Longer intervals are advisable in young children. The examination as described above should be repeated in full and documented. When clinical circumstances prohibit completion of any steps in the clinical examination, these should be documented. When the full clinical examination, including both assessments of brain stem reflexes and the apnoea test, is conclusively performed, no additional testing is required to determine brain death. In some patients, skull or cervical injuries, cardiovascular instability, or other factors may make it impossible to complete parts of the assessment safely. In such circumstances, a confirmatory test verifying brain death is necessary. These tests may also be used to reassure family members and medical staff. Any of the suggested tests may produce similar results in patients with catastrophic brain damage who do not fulfill the clinical criteria of brain death. The confirmatory tests are.
Brain death can be certified by a single physician privileged to make brain death determinations. However, before a patient can become an organ donor, New York State law requires that the time of brain death must be certified by the physician who attends the donor at his death and one other physician, neither of whom shall participate in the process of transplantation. This requirement ensures that all evaluations meet accepted medical standards, and that all participants can have confidence that brain death determination has not been influenced by extraneous factors, including the needs of potential organ recipients. When two physicians are required to certify the time of death, i.e., when organ donation is planned, both physicians should affirm that the clinical evaluation meets accepted medical standards, and that the data fully support the determination of brain death. Generally, both physicians should observe the patient, review the medical record, and note whether any additional information is required to make a definitive determination. Neither physician should certify brain death unless all aspects of the determination have been completed. Medical Record Documentation: All phases of the determination of brain death should be clearly documented in the medical record; The medical record must indicate:
When a patient is certified as brain dead and the ventilator is to be disconnected, the family should be treated with sensitivity and respect. If family members wish, they may be offered the opportunity to attend while the ventilator is disconnected. However, family members should be prepared for the possibly disturbing clinical activity that they may witness when organ donation is contemplated, ventilatory support will conclude in the operating room and family attendance is not appropriate. Determination of Brain Death in Children Less Than One Year of Age
The recommended observation period depends on the age of the patient and the laboratory tests utilized. It is assumed that the child was born at full term Between the ages of 2 months and 1 year, an interval of at least 24 hours should be used. Between the ages of 7 days and 2 months, the minimum interval should be 48 hours.
Source of Support: Nil Conflict of Interest: None declared. 1. Uniform Determination of Death Act, 12 Uniform Laws Annotated (U.L.A.) (West 1993 and West Supp 1997) 2. Guidelines for the determination of death: Report of the medical consultants on the diagnosis of death to the President's commission for the study of ethical problems in medicine and biomedical and behavioral research. JAMA. 1981;246:2184–6. [PubMed] [Google Scholar] 3. The Quality Standards Subcommittee of the American Academy of Neurology. Practice parameters: Determining brain death in adults. Neurology. 1995;45:1012–4. [PubMed] [Google Scholar] 4. Florida State Statutes. Available from: http://www.leg.state.fl.us/statutes [cited in 2004] 5. >Withholding and withdrawal of life sustaining equipment: Patient with brain death for adults and minors. Orlando regional healthcare policy #1725. Revision date 1/04. [Google Scholar] 6. Wijdicks EF. Determining brain death in adults. Neurology. 1995;45:1003–11. [PubMed] [Google Scholar] 7. Wijdicks EF. The diagnosis of brain death. N Engl J Med. 2001;344:1215–21. [PubMed] [Google Scholar] 8. Belsh JM, Blatt R, Schiffman PL. Apnea testing in brain death. Arch Intern Med. 1986;146:2385–8. [PubMed] [Google Scholar] 9. Goudreau JL, Wijdicks EF, Emery SF. Complications during apnea testing in the determination of brain death: Predisposing factors. Neurology. 2000;55:1045–8. [PubMed] [Google Scholar] 10. Sapsosnik G, Rizzo G, Vega A, Sabbatiello R, Deluca JL. Problems associated with the apnea test in the diagnosis of brain death. Neurol India. 2004;52:342–5. [PubMed] [Google Scholar] 11. Willatts SM, Drummond G. Brainstem death and ventilator trigger settings. Anesthesia. 2000;55:676–7. [PubMed] [Google Scholar] Articles from Indian Journal of Critical Care Medicine : Peer-reviewed, Official Publication of Indian Society of Critical Care Medicine are provided here courtesy of Indian Society of Critical Care Medicine |