LAUSR

Lewis et al.1 developed the largest and most complete assessment ever performed for identifying similarities and differences in protocols on determination of brain death/death by neurologic criteria (BD/DNC). The authors found substantial variability in protocols, which might partially explain why quarrelsome brain-dead cases have recently raised up new disputes on accepting BD.2,3 The presence of primary posterior fossa lesions enforces the needs of “aligning the criterion and tests for brain death.”4 In some patients fulfilling clinical BD criteria, when a posterior fossa lesion does not provoke an important increment of intracranial pressure, there may be not a full absence of cerebral blood flow, explaining preservation of EEG activity, evoked potentials, and autonomic function in some cases.3 Some authors commented that in the case of isolated brain-stem lesions, sparing the mesopontine tegmental reticular formation, this condition would theoretically lead to a fully apneic locked-in syndrome—which imitates brainstem death—with the possibility of retaining some degree of consciousness for some time, even fulfilling clinical BD criteria.5 This was the case in Jahi McMath.3 Further research and discussion are necessary concerning the use or not of ancillary tests in BD diagnosis, in the presence of primary posterior fossa lesions.