Confronted with just about any clinical question, my general practice is to first1After proceeding through the traditional neurological formulation, of course. consider whether there is high-quality evidence to guide decision-making. The best place to search for such evidence is in clinical practice guidelines that summarize and criticize the relevant literature and offer recommendations for specific clinical scenarios.2Of course, practice guidelines exist for only a fraction of the scenarios that we encounter, but almost any clinical question can be widened out to some general case. The evidence regarding management of that general case can then serve as a starting point for a decision regarding the specific situation at hand. For questions regarding acute stroke treatment or prevention, I think that the American Stroke Association guidelines are are the most authoritative resource. When it comes to the determination of death by neurological criteria, the American Academy of Neurology (AAN) guideline is the definitive document. Or so I thought.
The case, as so many of these are, is tragic: About a year ago, 20 year old Aden Hailu presented to the ED for acute abdominal pain. No cause was apparent, and she underwent an exploratory laparotomy. The procedure was complicated by hemorrhagic shock, which caused severe anoxic brain injury. About two months later, she was determined to have fulfilled neurological criteria for death and hospital staff sought to discontinue physiological support. Her father petitioned the courts to prevent hospital staff from doing so, but the district court ruled in the hospital’s favor because the medical testimony showed that the AAN guidelines regarding the determination of death by neurological criteria had been followed.
The Nevada supreme court reversed this decision and remanded the case back to the district court for further exploration of two crucial questions related to the Uniform Determination of Death Act (UDDA) that they felt were insufficiently addressed at the district level. I’m going to address the first question here and the second in a follow-up post.
Before taking up the court’s findings, a quick word about the UDDA: The purpose of the UDDA is to promote uniformity in the determination of death, especially when determined by neurological criteria, so that a person determined to be dead in one state would not be considered to be alive in another. All 50 U.S. states have either adopted this law or passed their own, essentially identical, one. The UDDA states that “An individual who has sustained either (1) irreversible cessation of circulatory and respiratory functions, or (2) irreversible cessation of all functions of the entire brain, including the brain stem, is dead.” Furthermore, the determination of death “must be made in accordance with accepted medical standards” and applied and construed in a manner “uniform among the states which enact it.”
The Nevada supreme court found that the district court and the hospital failed to demonstrate that the AAN guideline on brain death is an “accepted medical standard”. They cite evidence that practices regarding the determination of death by neurological criteria actually vary widely in the U.S. (here’s an even more recent report on that point) and they found that “. . . extensive case law demonstrates that at the time states began to adopt the UDDA, the uniformly accepted medical standard that existed was the then so-called Harvard criteria.” The Harvard criteria refer to a seminal 1968 report titled, A Definition of Irreversible Coma: Report of the Ad Hoc Committee of the Harvard Medical School to Examine the Definition of Brain Death. It’s a very important source document for anyone interested in brain death; unfortunately, I couldn’t find a free, full-text link. The AAN guideline comports closely with the procedures described in this report, with two exceptions: The Harvard report considered an isoelectric EEG tracing to have “great confirmatory value”, whereas the AAN guideline states that “In adults, ancillary tests are not needed for the clinical diagnosis of brain death and cannot replace a neurologic examination.” Second, the Harvard report states that “All of the above tests shall be repeated at least 24 hours later with no change”, whereas the original 1995 AAN guideline recommended a confirmatory examination at 6 hours and the 2010 update is silent on this point.
That practices regarding the determination of death by neurological criteria vary widely is quite concerning. It is therefore somewhat ironic that the AAN guidelines, intended in part to bring uniformity to this endeavor, may not withstand scrutiny. Complicating matters is the fact that Ms. Hailu has since satisfied cardiopulmonary criteria for having died, so I don’t know if the district court is going to consider the issue moot or continue to adjudicate it. Regardless, this case should prompt neurologists and hospitals to examine their protocols for making brain death determinations.
Notes / References [ + ]
|1.||↵||After proceeding through the traditional neurological formulation, of course.|
|2.||↵||Of course, practice guidelines exist for only a fraction of the scenarios that we encounter, but almost any clinical question can be widened out to some general case. The evidence regarding management of that general case can then serve as a starting point for a decision regarding the specific situation at hand.|