Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Brain Death”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 37 records · Page 2Linked to original sources

Medical and legal considerations of brain death.

Brain death was first defined in 1968, and since then laws on determining death have been implemented in all countries with active organ transplantation programs. As a prerequisite, the aetiology of brain death has to be known, and all reversible causes of coma have to be excluded. The regulations for the diagnosis of brain death are most commonly given by the national medical associations, and they vary between countries. Thus, the guidelines given in the medical textbooks are not universally applicable. The diagnosis is based on clinical examination, but confirmatory tests, such as angiography or EEG, are allowed on most occasions. Brain death is followed by cardiovascular and hormonal changes, which have implications in the management of a potential organ donor. Spinal reflexes are preserved, and motor and haemodynamic responses are frequently observed in brain dead patients.

Brain Death↗

[Vasopressin and brain death].

Brain death results in the breakdown of effective central regulatory mechanisms of cardiocirculatory stability, even in patients with artificial mechanical ventilation, correction of electrolytic and acid-basic disorders and maximal conventional pharmacological support of the circulation. Recent evidences have shown that the fall of vasopressin levels in the blood circulation significantly influences the cardiocirculatory stability of patients with brain death, and its exogenous administration is defended by many authors for the management of multiorgan donor patients. In this brief review we analyse and discuss some experimental and clinical relevant studies about the role of vasopressin in the control of cardiocirculatory stability in brain death, and its potential usefulness in the management of multiorgan donor. We conclude that the role of vasopressin in the pathophysiology of brain death and its usefulness as a pharmacological agent in the management of multiorgan donor are not well elucidated, deserving further investigations.

Brain Death↗

Drugs and brain death.

Brain death protocols facilitate early recognition of death in patients on life support systems. When the clinical situation has deteriorated to a level where brain death is to be considered, it is essential that the effects of drugs be excluded. Most centrally acting drugs depress respiration and would be expected to affect apnoea testing of brain stem function. However, the pharmacodynamic and pharmacokinetic properties of drugs are altered when patients are critically ill, so projections made from data derived from less ill patients or normal volunteers are inappropriate. The entry of drugs into the brain is also altered in some disease states, but there are few data relating to the effects of central depressant drugs in the situation of a disrupted blood-brain barrier or brain damage. Drug screens can assist in determining whether drugs are present, but correct interpretation of the results depends on close liaison between the clinical and laboratory staff. It is in the patient's interests to avoid termination of life support if any centrally active drug is present, unless there are other categorical factors consistent with irreversible brain death, such as demonstrated lack of cerebral blood flow.

Blood-Brain Barrier↗

Current considerations in the issue of brain death.

Brain death is an anatomically and physiologically complex process. The societal and psychological implications of brain death and organ donation are equally complex, and they have profound ramifications. Because the vast majority of organ donors die as a consequence of catastrophic intracranial processes, neurosurgeons are in a unique position to positively influence the supply of transplantable organs. Enhanced knowledge of the physiology of evolving brain death will improve the care of potential organ donors and increase the probability of successful transplantation. Likewise, better information about patient and family directives, beliefs, grieving, concurrent exposure to other health care workers, and experiences in the hospital environment will assist the neurosurgeon in providing the family with the opportunity for donation. Neurosurgeons can also play a leading role in the multidisciplinary approach required to support the families of potential organ donors during the transition from neurointerventional therapy to somatic support. New federal regulations on organ donation and a review of the literature about the "art of asking" are presented.

Advance Directives↗

[Criteria and diagnosis of brain death].

"Brain death" ist the irreversible loss of function of the whole brain. The syndrome is identical with individual death. The correct determination of brain death is important as further treatment makes no sense and as tissue donation now can be taken into account. The recommendations of the scientific advisory board of the German General Medical Council for determination of brain death from 1986 as well as the own experiences with the "brain death syndrome" and the preparations for tissue donation are discussed.

Brain Death↗

Brain death.

Brain death occurs whenever there is involvement of higher centers such as Cerebral Cortex and Thalamus (unresponsiveness and deep coma) and Brainstem and Basal ganglionic structures (loss of spontaneous respiration all cranial nerve, and postural reflexes). Involvement of Spinal Cord is less constant. Drug intoxication should be excluded. An electroencephalogram may be done but what is paramount is the physician's clinical judgment. The medico-legal implications of brain death is less complicated than it is generally presumed to be. It is extablishment of the legality of brain death concept that is crucial. This allows the physician to use his judgment to implement the law.

Brain Death↗

[Brain death--a certain sign of death].

Brain death means a complete and irreversible loss of all brain activity during intensive care with mechanical ventilation. On autopsy is seen an ischemic infarct of the whole brain following the stopped blood flow in the intracranial cavity after the elevation of the pressure. With brain death a human being loses two characteristics of its earthly life, the physical base needed for his spirit and his soul in this world, and the integration, the unity as the independent and self-contained organism.

Autolysis↗

Brain death and brain life: rethinking the connection.

The connection between brain life and brain death is neither as simple nor as defensible as it might at first appear. The problem rests with the two dominant competing definitions of death:...the loss of that which is necessary for the organism to continue to function as a whole;....the loss of that which is essentially significant to the nature of the organism... If death is understood as the loss of that which is necessary for the continued functioning of the organism as whole, then the apparent symmetry breaks down. If...death could be understood as the loss of that which is essentially significant to the nature of the organism....consciousness, then the symmetry would hold. However, that definition of death is indefensible. Therefore...statements about the status of anencephalic infants and early human embryos based upon a connection between brain death and brain life are unfounded.

Adult↗

Confirmation of brain death using brain radionuclide perfusion imaging technique.

OBJECTIVE: To determine the reliability of radionuclide cerebral blood perfusion imaging in confirming brain death irrespective of continued heartbeat. SUBJECTS AND METHODS: Twenty-eight patients (19 male and 9 female, aged 17-63 years) with severe brain injury and fully supported until the final cardiac asystole were included in the study. Two sets of clinical tests aimed at ascertaining brain death in each subject were performed separately for each case within an interval of 24 h. Dynamic, planar and single photon emission computed tomographic (SPECT) brain scintigraphy were also performed after intravenous administration of 550 MBq (15 mCi) technetium-99m hexamethyl propyleneamine oxime. RESULTS: Following the clinical diagnosis of brain death, none of the patients was withdrawn from cardiopulmonary support or had any organ harvested. Dynamic, planar and SPECT imaging performed thereafter did not reveal any intracranial cerebral perfusion in any of the subjects, except in 1 patient where the initial scan showed posterior fossa activity that ceased, in a subsequent scan obtained after 24 h. All of the patients were declared dead only after the emergence of cardiac asystole. CONCLUSION: The findings indicate that radionuclide brain perfusion imaging is reliable, reproducible, noninvasive and simple to perform for the confirmation of brain death and as such we recommend it as an alternative to exhaustive neurophysiological tests and invasive catheter angiography.

Adolescent↗

On asking the right questions: personal death vs. brain death in Japan.

This article addresses methodological concerns encountered during the author's recent fellowship tenure at the University of Tokyo's School for International Health. His research addressed matters relating to Japanese views of personal death within the context of the relationship between self and body. He was also interested in learning more about the extent to which these same views influence issues in medical ethics, particularly the ongoing debate over brain death and heart transplantation, which, until June 1997, was legally prohibited. One critical component in methodology involved interviews and discussions with prominent scholars representing various disciplines. The key feature in these meetings centered around specific core questions. The author describes how these questions underwent significant modifications, and discusses how these methodological adjustments in effect reveal notions that are substantive and relevant to the research design pertaining to Japanese views of death, self, and embodiment.

Attitude to Death↗

[Intervened death: from brain death to withholding or withdrawal of life-sustaining treatment].

The concept of intervened death accounts for all those situations in which the withholding or withdrawal of life-sustaining treatment constitutes a limit to therapeutic action associated to the occurrence of the traditional cardio-respiratory death. The 1968 Harvard Report advanced a new definition of death through the concept of complete cessation of global brain functions and, more than thirty years later, this process of intervention in its diagnosis may be seen as a continuum link to the need to procure organs for transplant purposes and the need to avoid long agonies in unrecoverable patients. During the last decade, the ethical admissibility of withdrawing ordinary and advanced life-sustaining therapy in cases that do not amount to brain death diagnosis--such as vegetative states and other irreversible clinical situations--and even the advances made for purposes of obtaining organs for transplant purposes in these situations (with the explicit authorization of the donor or his/her representative) allows a joint interpretation of these situations through the acceptance that limits may be established in medical assistance. Reflection on intervened death as an emerging phenomenon of our culture is mandatory so that society may get involved in an issue of its absolute and exclusive interest.

Brain Death↗

[Organ transplantation, ethics and culture in Japan. Japanese citizens may choose between cardiac death and brain death].

The first heart transplantation in Japan was performed in 1968. However, the surgeon was prosecuted, and transplantations from cadaveric donors came to an end. A new law in 1997 offered the possibility to choose how one would be pronounced dead, and if one chose to be declared dead according to brain related criteria, then one could become a cadaveric donor, if certain conditions were fulfilled. The first donations and transplantations took place in 1999. The Japanese public has been reluctant to accept the concept of brain death. The integrity of the dead body seems to command greater respect in Japan than in Sweden, and there is a reluctance to treat body parts as exchangeable. At the same time many Japanese travel abroad to obtain organs. The act of 1997 is a very interesting way of trying to integrate a new technology in Japanese culture, and the process of obtaining informed consent from relatives relies on traditional cultural roles.

Brain Death↗

Distinct transcriptional changes in donor kidneys upon brain death induction in rats: insights in the processes of brain death.

Brain death affects hormone regulation, inflammatory reactivity and hemodynamic stability. In transplant models, donor organs retrieved from brain dead (BD) rats suffer from increased rates of primary non-function and lower graft survival. To unravel the mechanisms behind brain death we have performed DNA microarray studies with kidney-derived RNA from normo- and hypotensive BD rats, corresponding with optimal and marginal BD donors, respectively. In kidneys from normotensive donors 63 genes were identified as either up- (55) or down-regulated (8), while 90 genes were differentially expressed (67 up-regulated) in hypotensive BD donor kidneys. Most genes were categorized in different functional groups: metabolism/transport (including the down-regulated water channel Aqp-2), inflammation/coagulation (containing the largest number (16) of up-regulated genes including selectins, Il-6, alpha- and beta-fibrinogen), cell division/fibrosis (including KIM-1 involved in tubular regeneration) and defense/repair (with the cytoprotective genes HO-1, Hsp70, MnSOD2). Also, genes encoding transcription factors (including immediate early genes as Atf-3, Egr-1) and proteins involved in signal transduction (Pik3r1) were identified. Summarizing, the use of DNA microarrays has clarified parts of the process of brain death: Brain-death-induced effects ultimately lead, via activation of transcription factors and signal transduction cascades, to differential expression of different "effector" genes. Not only deleterious processes such as inflammation and fibrosis occur in brain dead donor kidneys but genes involved in protection and early repair processes are activated as well. These findings can be used to introduce specific cytoprotective interventions in the brain dead donor to better maintain or even increase organ viability.

Animals↗

Brain death: epidemiology and quality control of solid organ donor generation.

Successful solid organ transplant programs need effective organ procurement systems. Evaluating and maintaining the quality of an organ procurement system requires multilevel institutional coordination as well as reliable information regarding potential donors. The objective of this study was to analyze the potential to generate adult solid organ donors at a countrywide level as well as at individual hospital levels in Uruguay from 2000 to 2002. The analyzed factors included: encephalic deaths (brain deaths) officially registered by the National Bank of Organs and Tissues (BNOT), the distribution of these individuals among the intensive care units (ICUs) located at various hospitals, the number of Real Donors at each hospital, and the relation between the brain deaths and the number of ICU beds equipped with artificial respirators. The Uruguayan solid organ donation rate is relatively high among Latin American Countries, but low in relation to developed countries. The conversion of potential donors to actual donors is similar to that seen in developed countries. However, the registered incidence of brain deaths in relation to the number of ICU beds is surprisingly below the recognized standard figure. To approach the reasons for this difference, efficient quality control mechanisms are needed in the various ICUs as well as comprehensive medical case history reviews of all patient records.

Brain Death↗