Brain death and management of the potential donor

Abstract

One of the first attempts to define brain death (BD) dates from 1963, and since then, the diagnosis criteria of that entity have evolved. In spite of the publication of practice parameters and evidence-based guidelines, BD is still causing concern and controversies in the society. The difficulties in determining brain death and making it understood by family members not only endorse futile therapies and increase health care costs, but also hinder the organ transplantation process. This review aims to give an overview about the definition of BD, causes, physiopathology, diagnosis criteria, and management of the potential brain-dead donor. It is important to note that the BD determination criteria detailed here follow the AAN's recommendations, but the standard practice for BD diagnosis varies from one country to another.

Keywords: Brain death; Critical care; Diagnosis; Management; Organ donation.

Fig. 1

Brain death (BD) diagnosis. Ancillary tests may be required when the clinical assessment or the apnea test cannot be performed properly (e.g., acute or pre-existing ophthalmologic conditions; facial and skull trauma; pre-existing cranial neuropathies; chronic respiratory acidosis). In some countries, the ancillary tests are mandatory for the diagnosis of BD. One clinical examination (coma, absence of brainstem reflexes, and apnea) positive to BD is sufficient to the diagnosis, but some centers require 2 positive assessments. “YES” meaning fulfilling criteria to BD diagnosis in the respective step; “NOT” meaning not fulfilling criteria to BD diagnosis in the respective step

Fig. 2

Apnea test. To undergo the apnea test, the patient must be hemodynamically stable. A positive apnea test supports the clinical diagnosis of BD. When the patient is hemodynamically stable during the test, but the result is inconclusive, the patient must be preoxygenated again, and the test must be repeated for 10–15 min