Brain death determination: still a lot to learn, still a lot to do….

Abstract

Human life is book-ended by two major events, birth and death. Although all are born the same way, since the invention of ventilators and ICUs humans can die either by cardiorespiratory arrest or by irreversible cessation of all brain functions [the so-called death by neurological criteria or ‘‘brain death (BD)’’]. Diagnosing the former is an easy process requiring an electrocardiogram or a stethoscope. Diagnosing the latter, however, is a complex process that requires experience. There is wide-spread variability across countries or across states and hospitals in the US on how patients are pronounced BD [1]. There are also many unanswered questions regarding the BD process and, because of the lack of high-level evidence, continuous challenge of its core notions by a substantial minority of physicians. In fact, few years ago, when the American Academy of Neurology BD Guidelines were revised, and a panel of experts attempted to answer five basic questions, they concluded that in 4/5 questions the level of evidence was U (data inadequate or conflicting) and in 1/4 level C (possibly effective, ineffective, or harmful for the given condition in the specified population) [2]. Therefore, any attempts to conduct quality research and answer questions pertaining to BD are more than welcomed. In this issue of Neurocritical Care, our readers will find four studies that try to address four different BD problems. In the first paper Citerio et al. [3], examined the variability in BD determination in 28 European countries that responded to a survey. Across the Atlantic, variability occurs in State laws, hospital policies, bedside performance of physicians, and documentation of BD [1, 4]. Therefore, it is no surprise to report that variability also exists across European countries. Basic prerequisites such as normal core temperature or blood pressure were not required in one and ten countries, respectively. Clinical exam alone was sufficient in 50 % of countries and in the rest some ancillary test was required. Important parts of the clinical exam, such as the gag reflex, were not defined in six countries and the apnea test details in four. The number of clinical exams varied from 1 to 3 and the time interval between exams from no minimum to 12 h. The list can go on, but the reader, like the authors, can easily conclude one of two things: that an international consensus on BD determination is imperative and that some clinical competency requirement [5] or check lists (like those used in the operating room or the one provided by the AAN [2]) may put further order into an already chaotic situation. One step in the right direction is the paper by MacDougall et al. [6]. The authors describe a BD didactic course and simulation exercise that they developed at Yale. A set of questions was administered before the didactic session and after the simulation. The authors report that there was a significant improvement in responses, which initially were correct in only 41.5 % of the time. Interestingly, even neurointensivists (who ostensibly are performing BD determinations regularly) answered correctly no higher than 56.6 % of the time in the pre-test. Attendings in neurology or neurosurgery scored higher in both pre-test and the 26-point clinical exam than other specialties. The authors should be commended for this effort. Although there was no scripted mention of coma in a patient to be examined for BD and their course is a rather expensive approach (not all hospitals have manikins with pupillary reactivity capability!), this is an excellent initial effort that could be easily adopted and customized widely. Long-term effect of this intervention should also be assessed in the future, since lack of frequent real-life P. Varelas (&) Henry Ford Hospital, Detroit, USA e-mail: PVARELA1@hfhs.org