Experts in brain death/death by neurologic criteria (BD/DNC) have convened to publish a consensus statement on global recommendations for determining brain death/death (BD/DNC) by neurologic criteria, according to results published in JAMA.
Throughout the world, there have been inconsistencies in evaluating BD/DNC. Consequently, study researchers sought to develop a consensus statement of recommendations for determining BD/DNC.
Experts from the World Federation of Intensive and Critical Care, the World Federation of Pediatric Intensive and Critical Care Societies, the World Federation of Neurology, the World Federation of Neurosurgery, and the World Federation of Critical Care Nurses were recruited to determine these recommendations. Consensus statements were made based on literature searches of the Cochrane, Embase, and MEDLINE databases. This included data from January 1992 to April 2020.
In their paper, the consensus authors stated that the first criteria that must be fulfilled prior to evaluating a patient for BD/DNC is to establish a neurologic diagnosis that could lead to either complete or irreversible loss of all brain function. Additionally, clinicians must exclude all conditions that may confound the examination, including diseases that mimic BD/DNC prior to evaluation.
A clinical examination for determination of BD/DNC would involve identifying coma, defined as no evidence of awareness, wakefulness, or arousal to maximal external visual, auditory, and tactile stimulation. Regarding pupillary reflexes, pupils should be nonreactive to light and fixed in a dilated or midsize position. Corneal, oculocephalic, and oculovestibular reflexes should be absent. The consensus statement additionally noted that the patient should not demonstrate any facial movement in response to noxious cranial stimulation. There should also be no gag reflex to bilateral posterior pharyngeal stimulation.
Additionally, a clinical examination for BD/DNC should demonstrate an absent cough reflex to deep tracheal suctioning. No brain-mediated motor response to noxious stimulation of the limbs should be present. Finally, the clinical examination should not be able to reveal spontaneous respirations when apnea test targets reach a pH of less than 7.30 and PaCO2 of at least 60 mm Hg.
Ancillary testing is recommended with either blood flow studies or electrophysiologic testing in the case where a clinical examination cannot be performed or completed. Clinicians should take careful consideration of certain religious, societal, and cultural perspectives prior to examination. Other special considerations that must be made are those involving children, patients receiving extracorporeal membrane oxygenation, and those receiving therapeutic hypothermia.
According to the study authors, a limitation of the consensus was that there was a lack of high-quality randomized data from large studies and clinical trials, which prevented their use of the GRADE, AGREE, and other analytic approaches. Additionally, not all countries may be able to adopt these recommendations in entirety.
These recommendations, the study authors concluded, “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.”
Greer DM, Shemie SD, Lewis A, et al. Determination of brain death/death by neurologic criteria: the world brain death project. JAMA. Published online, August 3, 2020. doi:10.1001/jama.2020.11586