Was It Really Brain Death?
Twenty-one-year-old Zack Dunlap from Oklahoma appeared on NBC's Today Show in 2008 to tell an incredible story of hearing a physician telling his parents that a PET scan confirmed that he was brain dead after a catastrophic brain injury. While he was being prepared for organ donation, however, he moved his arm purposely in response to stimuli. Dunlap recovered, went to a rehabilitation hospital, and ultimately went home 48 days later, very much alive.
Earlier this year, 13-year-old Trenton McKinley from Alabama and his parents hit the media circuit to talk about the miracle of Trenton awakening after being declared brain dead from a vehicle accident—1 day before his organs were scheduled to be harvested.
The likely explanation for such "recoveries" from brain death, according to experts, is that these individuals were never brain dead in the first place. "Errors have been made where people declared brain dead were later found to have spontaneous movement that should not have been possible," says Robert M. Sade, MD, professor of surgery and director of the Institute of Human Values in Health Care at the Medical University of South Carolina in Charleston. "In virtually all those cases, brain-death determination was not done correctly. If you don't go through the exact protocol for brain-death determination, you're likely to have patients diagnosed as being dead by neurologic criteria who are, in fact, not brain dead."
A more typical brain death error is the 2011 case of a 55-year-old with brain injury who was treated with hypothermia to try to optimize neurologic recovery. He was declared brain dead 24 hours after he was rewarmed—which was too short a period of time. During preparation for organ procurement, it was noticed that he had regained some brainstem reflexes—he certainly wasn't fine—and, therefore, wasn't brain dead.
When the American Academy of Neurology (AAN) updated its guidelines for determining brain death in adults in 2010, a committee of experts searched the literature and found no legitimate "reports of patients recovering brain function when the criteria for brain-death determination was used appropriately," says Ariane K. Lewis, MD, associate professor, department of neurology and neurosurgery, NYU Langone Medical Center, New York City, and a member of the AAN's Ethics, Law, and Humanities Committee.
But at the same time there is no way of knowing how many people recover from brain death because they are usually quickly removed from life support or become organ donors.
Differing Diagnoses of Brain Death
Recently, however, the high-profile case of Jahi McMath has caused some experts to question whether brain-dead patients are truly dead and more families to legally fight a loved one's brain death diagnosis.
In 2013, McMath was 13 when complications from a tonsillectomy led to cardiac arrest and an anoxic brain injury. A pediatric neurologist, a pediatric intensivist, and a pediatric neurologist from another institution declared her brain dead, a diagnosis her family did not accept. Subsequently, two neurologists stated that McMath was not brain dead based on their interpretation of an EEG, an MRI, and an MRA done a year later and observation of video clips from 2014 to 2016 that appeared to show McMath following commands and communicating with finger movements.
"We have high confidence that McMath's initial diagnosis of brain death was correct," says Thaddeus Mason Pope, JD, PhD, director of the Health Law Institute and professor of law, Mitchell Hamline School of Law in St Paul, Minnesota. "It's never happened in human history that someone correctly diagnosed as brain dead is no longer dead."
To definitively prove that McMath had recovered sufficient brain function to be considered alive, two physicians would have had to conduct another formal determination of brain death to refute the initial one.
"If that were proven, that means that there is something wrong with how we diagnose brain death, because it's supposed to be an irreversible condition," Pope says. But that second evaluation was not done and never will be because McMath died from liver failure in June 2018, nearly 5 years after being declared brain dead.
Too Much Room for Error
James L. Bernat, MD, is one brain death expert who believes the current neurologic tests leave too much room for error, and, consequently, patients are being declared brain dead who aren't.
"There are a group of people who strongly believe that although McMath fulfilled the pediatric brain death criteria, she wasn't really brain dead because she retained certain brain functions," says Bernat, active emeritus professor of neurology and medicine at Dartmouth Geisel School of Medicine in Hanover, New Hampshire, and former chair of the AAN's Ethics, Law, and Humanities Committee. "If she wasn't really brain dead, which I believe to be the case, then it suggests that our tests are not fully accurate. Some of us have argued in response to McMath and other cases that have been published that we need to tighten up the tests to eliminate cases like this getting through in the future."
Making brain death criteria more rigorous, however, would likely reduce the number of brain-dead organ donors, who are the primary source of transplantable organs, including all hearts. Sade, who previously ran South Carolina's organ procurement program, stirs the brain death controversy in the opposite direction. He is advocating for potential organ donors who are nearly dead to have their organs harvested, which would make formal brain death determination unnecessary.
"Once a potential organ donor's death is imminent, I would like for us to be able to remove his organs even though he is still breathing, and his heart is beating," Sade says. Waiting until brain-injured patients progress to brain death results in physiologic abnormalities and organ damage from neurologic and hormonal changes, he says.
"Any organ donor would want the organs to be in the best possible condition and as many organs used as possible for transplantation." Sade estimates that as many as 6684 additional organs could be retrieved from brain-injured organ donors who were imminently dead rather than brain dead. "We could wipe out the waiting list for all organs for two or three years," he says.
A Steady State of Controversy
Declaring a patient dead based on the irreversible loss of all clinical brain function has been controversial since it was first proposed 50 years ago by a committee at Harvard Medical School. At the time, new resuscitative technology was able to keep the "hopelessly unconscious patient" alive, and physicians wanted to settle ethical issues about when to withdraw life support and how to advance the growing success of organ transplantation.
Ever since then, bioethicists and physicians in academia have quietly parleyed the ethics of brain death in clinical journals and at conferences. "The debated issues were that brain death isn't the same thing as death, that it is a contrived concept for the purposes of organ donation, that is outdated and antiquated, and other claims," Bernat says. "But until recently, those claims haven't generated much traction."
The controversial brain death determination of Jahi McMath changed the discourse, however. "When you have the New Yorker, the New York Times, and the Wall Street Journal writing about the Jahi McMath case, the volume on brain death gets turned up," Pope says. "Brain death has worked pretty well for 50 years, but there is a growing level of mistrust and skepticism, and we need to do something to bolster its legitimacy."
Brain death fulfills the medical and legal criteria of death in the United States and in about 100 other countries today. Every state in the United States has adopted the Uniform Determination of Death Act (UDDA), which defines death as the "irreversible cessation of circulatory and respiratory functions" or the "irreversible cessation of all functions of the entire brain, including the brain stem."
In addition, there is an informal ethical standard of organ procurement called the dead donor rule, which stipulates that a donor must be dead before vital organs are harvested.
Arguments Over the Criteria
But ethicists have always found the UDDA to be problematic. "The Uniform Determination of Death Act is a legal fiction because it requires irreversible loss of function," Sade says. "There are some patients who meet all the clinical criteria for brain death, and yet they still have cells in their brain that are neurologically active. They can survive for relatively long periods of time, although these cases are very infrequent. Usually they die within a matter of days after they meet neurologic criteria for brain death."
Organ donors who are declared dead after circulation ceases are also not irreversibly dead because they could have been resuscitated at the time organ harvesting commences. "Someone is not irreversibly dead until circulation stops for 10 to 20 minutes, but at that point, their organs are not useable," Sade says.
The disconnect between the legal definition of death—cessation of all functions of the entire brain—and the medical criteria—cessation of most brain functions—leaves brain death vulnerable to challenge, Pope says. "Either we have to ramp up the criteria to match the law with more rigorous diagnostic assessments," he says, "or we have to change the law to make it less demanding."
Should There Be Tougher Brain Death Standards?
Bernat acknowledges that he is among a small minority of physicians advocating for potentially more stringent brain death standards. "I think most neurologists, neurosurgeons, and intensive-care doctors are probably satisfied that the criteria are good enough," he says.
"I wouldn't immediately change the criteria, but we should try to determine how accurate our confirmatory tests are. The belief has been that these tests are infallible; maybe they aren't. There have always been questions about the test that shows the absence of intracranial blood flow, for example. Can it accurately distinguish zero flow from a very, very low rate of flow? A tiny trickle of blood may be enough to maintain certain brain perfusions. After we study these questions and reach some conclusions, then we can decide whether, as a matter of policy, we should change our brain-death testing standards."
The AAN's Lewis disagrees. "There is not concern that the current set of guidelines aren't strict enough by any means," she says. But there is consensus among brain death experts that all hospitals should follow current brain death guidelines to the letter—but they don't.
A 2016 study of 508 US hospitals' brain death protocols found that there were significant differences among hospitals in the number of examinations required to determine brain death as well as the waiting periods between examinations. Some institutions used unapproved or nonvalidated ancillary tests, and more junior doctors were allowed to declare patients brain dead in some hospitals; only a third of policies required the physician to have expertise in neurology or neurosurgery.
The AAN guidelines require a single neurologic examination and one apnea test to determine that an adult has no brainstem reflexes and is unable to breathe spontaneously. The pediatric brain death guidelines, created by the American Academy of Pediatrics in conjunction with the Child Neurology Society and the Society of Critical Care Medicine, require two separate physicians to conduct two neurologic examinations and two apnea tests separated by an observation period.
"Some of the variations among institutions are based on the desire to be extra-conservative and other variations are not well thought out," Lewis says. "That institutions have different protocols creates an issue of trust in the process of determining death. Brain death being determined in an inaccurate fashion because guidelines are not followed opens the door to stories of brain-death recovery."
The AAN recently outlined steps to try to make hospitals' brain death guidelines universal, such as having a regulatory body review and align institutions' policies with the guidelines and creating a single set of guidelines for adult and pediatric patients to simplify the process. "Variation has been going on for 50 years so it's not something that can be fixed in a short period of time," Lewis says.
In light of the Jahi McMath case and recent lawsuits by other families challenging the validity of brain death, it's time for "an august, interdisciplinary committee of physicians and philosophers" to revisit the medical and legal standards for brain death, Pope says.
Ultimately, however, "brain-death determination requires an arbitrary decision on when someone is dead enough," Pope says. "There will never be zero activity in the brain (at brain death). At some point, you have to make a value judgement of what is meaningful brain activity. There is no objective truth on where to draw that line."
1. Celizic M. Pronounced dead, man takes 'miraculous' turn. Today.com. October 14, 2016. Source Accessed September 10, 2018.
2. Hetherington J. Alabama boy makes miracle recovery after parents agree to donate his organs. Newsweek. May 7, 2018. Source Accessed September 10, 2018.
3. Debolt D. More families now challenging doctors' brain-death diagnoses. Seattle Times. May 18, 2016. Source Accessed September 10, 2018.
4. Greer D, Wang H, Robinson J. Variability of brain death policies in the United States. February 2016. Source Accessed September 10, 2018.