Frequent Preservation of Neurologic Function in Brain Death and Brainstem Death Entails False-Positive Misdiagnosis and Cerebral Perfusion

Abstract

Some patients who have been diagnosed as "dead by neurologic criteria" continue to exhibit certain brain functions, most commonly, neuroendocrine functions. This preservation of neurologic function after the diagnosis of "brain death" or "brainstem death" is an ongoing source of controversy and concern in the medical, bioethics, and legal literatures. Most obviously, if some brain function persists, then it is not the case that all functions of the entire brain have ceased and hence, declaring such a patient to be "dead" would be a false positive, in any nation with so-called "whole brain death" laws. Furthermore, and perhaps more concerning, the preservation of any brain function necessarily entails the preservation of some amount of brain perfusion, thereby raising the concern as to whether additional areas of neural tissue may remain viable, including areas in the brainstem. These and other considerations cast significant doubt on the reliability of diagnosing either "brain death" or "brainstem death."

Radionuclide Evaluation of Brain Death in the Post-McMath Era: Epilogue and Enigmata

“…Jahi's course was also exceptional in that most patients declared BD immediately proceed to organ donation or are removed from the ventilator leaving no opportunity for subsequent observation; under these circumstances, the frequency of delayed return of function cannot be estimated. In spite of this paradigm, occasional case reports have surfaced where neurologic function is noted to return following pronouncement of BD (7), similar to our narrative. Several medical personnel, including a prominent pediatric neurologist, came to believe that Jahi could intermittently respond in a purposeful manner to verbal commands (such as "move your arm") (2).…”

Spinal reflexes and brain death

“…Furthermore, half of patients declared to be brain dead have preserved osmoregulation ( Nair-Collins and Joffe, 2021a ). This demonstrates arterial flow and venous drainage from magnocellular cell bodies in the hypothalamus as well as the posterior pituitary ( Nair-Collins and Joffe, 2021b ). This has been observed even when imaging shows intracranial circulatory arrest ( Nygaard et al, 1990 , Varelas et al, 2011 ; cf.…”

“…This has been observed even when imaging shows intracranial circulatory arrest ( Nygaard et al, 1990 , Varelas et al, 2011 ; cf. Nair-Collins and Joffe, 2021b for discussion).…”

Must Hypothalamic Neurosecretory Function Cease for Brain Death Determination? No

“…2 In the United States, the word “entire” has also generated debate, with a small minority arguing that when used to the letter, up to half of brain dead (BD) patients are erroneously diagnosed as dead and, in fact, when heart-beating organ donation follows, these mistakenly diagnosed dead patients may be considered homicide victims. 3 I will try to refute this proposition.…”

“…6 In review articles, 50%–60% of adult and 52% of pediatric BD patients were diagnosed with DI. 3,7 The authors of these review articles speculate that hypothalamic and pituitary functions were still present. This argument is problematic for many reasons: First, not every study used rigorous diagnostic criteria for central DI.…”