Short latency evoked potentials: new criteria for brain death?

Journal of Zhejiang University SCIENCE B, 2008

Objective: Optimization of combining electroencephalography (EEG), short latency somatosensory evoked potentials (SLSEP) and transcranial Doppler (TCD) techniques to diagnose brain death. Methods: One hundred and eleven patients (69 males, 42 females) from the major hospitals of Zhejiang Province were examined with portable EEG, SLSEP and TCD devices. Re-examinations occurred ≤12 h later. Results: The first examination revealed that the combination of SLSEP and EEG led to more sensitive diagnoses than the combination of SLSEP and TCD. Re-examination confirmed this and also revealed that the combination of TCD and EEG was the most sensitive. Conclusion: The results show that using multiple techniques to diagnose brain death is superior to using single method, and that the combination of SLSEP and EEG is better than other combinations.

2009

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, a...

Neurophysiologie clinique = Clinical neurophysiology, 2016

To assess whether Somatosensory Evoked Potentials (SEPs), recorded within 24h after ICU admission, are reliable predictors of brain death (BD) in comatose patients with acquired brain injury of various aetiologies. SEPs were classified as absent (A), pathological (P), and normal (N). Considering SEP recordings from both hemispheres, 6 patterns were identified: NN, NP, PP, NA, AP, and AA. The final endpoint was BD. Of the 203 patients included in the study, 70 (34%) evolved toward BD. The survival analysis indicated that the combination of SEP patterns in a two-graded scale (grade 1: NN-NP-PP-NA, and grade 2: AP-AA), allowed for prediction of BD with the best accuracy. This aggregation predicted BD with a sensitivity of 75.7% (CI: 64-84), a specificity of 76.6% (CI: 68-83), a positive predictive value of 64.2% (CI: 53-74) and a negative predictive value of 84.3% (CI: 77-90) in overall patients, and with a sensitivity of 75.0% (CI: 63-84), a specificity of 84.9% (CI: 75-90), a positiv...

Neurological Sciences

Background We aimed to verify the usefulness of electroencephalographic (EEG) activity recording (that is mandatory according to the Italian law), in addition to two clinical evaluations spaced 6 h, among the procedures of brain death determination (BDD) in adult individuals. Methods The study is a monocentric, retrospective analysis of all BDDs performed in the last 10 years at Policlinico Le Scotte in Siena (Italy). Results Of the 428 cases revised (mean age 67.6 ± 15.03 years; range 24–92 years), 225 were males and 203 females. In total, 212 out of 428 patients (49.5%) were donors. None of the BDD procedures were interrupted due to the reappearance of EEG activity (neither for clinical reasons) at any sampling time, with the exception of one case that was considered a false negative at critical reinspection of the EEG. In 6/428 cases (1.4%), a cardiac arrest occurred during the 6 h between the first and second evaluation, thus missing the opportunity to take organs from these pat...

Canadian Journal of …, 2006

Canadian Journal of Anesthesia/Journal canadien d'anesthésie, 2006

Purpose: Despite general worldwide acceptance of the concept of neurological determination of death (NDD), inconsistencies in clinical criteria and ancillary testing requirements remain. Numerous guidelines for NDD may be applied in clinical practice by a variety of medical practitioners, but the scientific rationale for specific guideline recommendations often remains unclear. This review examines the evolution of NDD, and seeks to provide scientific validation for existing NDD criteria. Source: English language peer-reviewed medical journals and established contemporary medical texts. Principal findings: Currently published guidelines appear to have evolved from the work of the ad hoc Committee of the Harvard Medical School to Examine the Definition of Brain Death. The Conference of the Royal Colleges and Faculties of the United Kingdom refined the criteria and subsequently adopted the principal of brainstem death. While the fundamentals of NDD guidelines are remarkably consistent worldwide, specific criteria and requirements are often inconsistent. Conclusion: Numerous controversies regarding NDD continue to exist, necessitating further scientific clarification of these issues. More recently published guidelines representing the collective opinion of world experts in NDD based upon best current scientific evidence are available in current medical journals. Objectif : Malgré l'acceptation mondiale du concept de détermination neurologique de la mort (DNM), un manque d'homogénéité persiste dans les critères cliniques et les exigences de tests accessoires. De nombreuses directives peuvent être appliquées pour la DNM par divers praticiens médicaux cliniques, mais le fondement scientifique des recommandations de pratique demeure souvent confus. La présente revue examine l'évolution de la DNM et cherche à donner une validation scientifique aux critères existants de DNM. Source : Des revues médicales de langue anglaise vérifiées par des pairs et des textes médicaux contemporains reconnus. Constatations principales : Les directives publiées présentement paraissent avoir évolué depuis le premier travail du Comité spécial de la Harvard Medical School chargé de définir la mort encéphalique. La Conference of the Royal Colleges and Faculties of the United Kingdom a raffiné les critères et subséquemment adopté le principe de mort du tronc cérébral. Quoique le fondement des directives sur la DNM soit remarquablement cohérent à travers le monde, les exigences et les critères spécifiques sont souvent irréguliers. Conclusion : Beaucoup de controverse continue d'exister en regard de la DNM, ce qui nécessite une clarification scientifique poussée. Des directives publiées plus récemment sont accessibles. Elles font part de l'opinion collective d'experts mondiaux en DNM, fondée sur la meilleure preuve scientifique actuelle.

Qjm, 1999

The necessity of defining brain death (BD) arose under misleading conditions (hypothermia, drugs, metabolic disturbances). In our experience, the use from technological development in medical science. The definition of this concept had practical con-of multimodality evoked potentials (MEPs) to confirm a BD diagnosis has many advantages: MEPs can sequences and opened the way to organ donation from BD patients. Nowadays, the imbalance be rapidly performed at the patient's bedside, assess the brain stem as well as the cerebral cortex, and between the number of organs available for transplantation and the size of the demand is becoming are innocuous for the patient. Moreover, their insensitivity to the aforementioned misleading fac-critical. In most laboratories, a BD diagnosis is made according to precise criteria and in a well-defined tors is sufficient to distinguish BD from clinical and EEG states that mimic BD. They give an immedi-process. BD diagnosis should be improved, not only to assure the safety and to preserve the human ate diagnosis, and no delay is required in BD confirmation if there is sufficient cause to account dignity of the patient, but also in order to increase the rate of organ donation. By analysing some epi-for BD. MEPs are a safe, accurate, and reliable tool for confirming a BD diagnosis, and their use can demiological parameters in BD diagnosis and organ donation, it appears that BD diagnoses can be made improve the organ donation rate while preserving the safety of the patient. more often and more rapidly if one has a reliable, accurate, and safe confirmatory test, especially

Journal of neuroimaging : official journal of the American Society of Neuroimaging, 2018

Brain death determination (BDD) is primarily a clinical diagnosis, where death is defined as the permanent loss of brainstem function. In scenarios where clinical examinations are inaccurate, ancillary imaging tests are required. The choice of ancillary imaging test is variable, but the common denominator for all of them is to establish a lack of cerebral blood flow. The purpose of this study was to compare the diagnostic accuracy and interrater reliability of different ancillary imaging tests used for BDD. Archival data were retrospectively analyzed for all patients who underwent any ancillary imaging test for BDD at our institution. The results of ancillary imaging tests were compared with, the reference standard, the clinical checklist for declaration of brain death. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of different ancillary imaging tests for BDD were performed. Interobserver agreement between two observers was measured u...

Nursing in Critical Care, 2004

The diagnosis of brain death as 'death' and organ transplantation have been closely historically linked since the mid twentieth century • It will be argued in this article that the development of a neurological definition of death was introduced to justify the removal of fresh viable organs for transplantation • Brain death cannot be diagnosed reliably using 'established practices' • Improved understanding of the pathophysiology of raised intracranial pressure has challenged our understanding of brain death • We need to move forward in our conceptualization of phenomenon of profound coma associated with massive brain damage • If examination for 'brain death' is to be carried out at all, there needs to be an examination and re-evaluation of practices and protocols

Neurosciences (Riyadh, Saudi Arabia), 2008

Brain death implies the permanent absence of all cerebral and brainstem functions. The diagnosis of brain death is usually made clinically. The criteria require the occurrence of acute and irreversible CNS insult. Drug intoxication, poisoning, metabolic derangements, and hypothermia should be corrected for accurate brain death evaluation. At least 2 expert examiners are required to make the brain death determination. It is advisable to involve an independent examiner not involved in the patients care or the recovery of donated organs. The objective of this article is to present updated guidelines for the process of brain death determination. All brain and brainstem functions should be absent on neurological examination including cerebral response to external stimuli and brain stem reflexes. An apnea test should be performed in all patients. However, if the clinical criteria cannot be applied, other confirmatory ancillary tests are required, particularly EEG, and radionuclide scan. T...