A consensus review involving five world federations and 33 medical societies spanning 25 countries has released recommendations for the minimum clinical standards for determination of brain death/death by neurologic criteria in adults and children. with guidance for various clinical circumstances.
The concepts of life and death have always been complicated, but ever more so as medical and technological advances continue to extend the limits to saving life and prolonging physiological function. For previous generations, cardio-respiratory death was the sole clinical definition of death, often without any standard criteria, leading to the risk of misdiagnosis. As resuscitation techniques and mechanical ventilation developed, a new definition of death was needed.
The idea of brain death/death by neurologic criteria (BD/DNC) was first recognised in 1959 as “coma depassé”1 and subsequently described as “brain death” with the first published clinical definition in 1968, commonly known as the Harvard Brain Death Criteria. Since then, many other guidelines and protocols have been published, adopted, and revised throughout the world with general acceptance of the concept of BD/DNC among medical groups, major religions, and governments.
However, there continues to be confusion and dilemmas that arise regarding BD/DNC.
The wide variance in practice reflects this confusion and numerous other challenges. Inconsistencies in concept, criteria, practice, and documentation exist internationally and within countries. Difficulties in conducting randomised clinical trials and large-scale studies on BD/DNC have resulted in a lack of robust data from which to develop evidence-based recommendations.
Challenges to the validity of BD/DNC continue to promote controversy. These factors initiated this project to harmonize practice and improve the rigor of BD/DNC determination.
Importance: There are inconsistencies in concept, criteria, practice, and documentation of brain death/death by neurologic criteria (BD/DNC) both internationally and within countries.
Objective: To formulate a consensus statement of recommendations on determination of BD/DNC based on review of the literature and expert opinion of a large multidisciplinary, international panel.
Process: Relevant international professional societies were recruited to develop recommendations regarding determination of BD/DNC. Literature searches of the Cochrane, Embase, and MEDLINE databases included January 1, 1992, through April 2020 identified pertinent articles for review. Because of the lack of high-quality data from randomized clinical trials or large observational studies, recommendations were formulated based on consensus of contributors and medical societies that represented relevant disciplines, including critical care, neurology, and neurosurgery.
Evidence Synthesis: Based on review of the literature and consensus from a large multidisciplinary, international panel, minimum clinical criteria needed to determine BD/DNC in various circumstances were developed.
Recommendations: Prior to evaluating a patient for BD/DNC, the patient should have an established neurologic diagnosis that can lead to the complete and irreversible loss of all brain function, and conditions that may confound the clinical examination and diseases that may mimic BD/DNC should be excluded. Determination of BD/DNC can be done with a clinical examination that demonstrates coma, brainstem areflexia, and apnea. This is seen when (1) there is no evidence of arousal or awareness to maximal external stimulation, including noxious visual, auditory, and tactile stimulation; (2) pupils are fixed in a midsize or dilated position and are nonreactive to light; (3) corneal, oculocephalic, and oculovestibular reflexes are absent; (4) there is no facial movement to noxious stimulation; (5) the gag reflex is absent to bilateral posterior pharyngeal stimulation; (6) the cough reflex is absent to deep tracheal suctioning; (7) there is no brain-mediated motor response to noxious stimulation of the limbs; and (8) spontaneous respirations are not observed when apnea test targets reach pH <7.30 and PaCO2 ≥60 mm Hg. If the clinical examination cannot be completed, ancillary testing may be considered with blood flow studies or electrophysiologic testing. Special consideration is needed for children, for persons receiving extracorporeal membrane oxygenation, and for those receiving therapeutic hypothermia, as well as for factors such as religious, societal, and cultural perspectives; legal requirements; and resource availability.
Conclusions and Relevance: This report provides recommendations for the minimum clinical standards for determination of brain death/death by neurologic criteria in adults and children with clear guidance for various clinical circumstances. The recommendations have widespread international society endorsement and can serve to guide professional societies and countries in the revision or development of protocols and procedures for determination of brain death/death by neurologic criteria, leading to greater consistency within and between countries.
David M Greer; Sam D Shemie; Ariane Lewis; Sylvia Torrance; Panayiotis Varelas; Fernando D Goldenberg; James L Bernat; Michael Souter; Mehmet Akif Topcuoglu; Anne W Alexandrov; Marie Baldisser; Thomas Bleck; Giuseppe Citerio; Rosanne Dawson; Arnold Hoppe; Stephen Jacobe; Alex Manara; Thomas A Nakagawa; Thaddeus Mason Pope; William Silvester; David Thomson; Hussain Al Rahma; Rafael Badenes ; Andrew J Baker; Vladimir Cerny; Cherylee Chang; Tiffany R Chang; Elena Gnedovskaya; Moon-Ku Han; Stephen Honeybul; Edgar Jimenez; Yasuhiro Kuroda; Gang Liu; Uzzwal Kumar Mallick; Victoria Marquevich; Jorge Mejia-Mantilla; Michael Piradov; Sarah Quayyum; Gentle Sunder Shrestha; Ying-ying Su ; Shelly D Timmons ; Jeanne Teitelbaum ; Walter Videtta ; Kapil Zirpe ; Gene Sung