In July 2024, a 46-year-old Kentucky man named Anthony Thomas "TJ" Hoover II was declared brain dead at Saint Joseph London Medical Center and transferred to the University of Louisville Hospital for organ donation. However, just before the organ retrieval surgery, he displayed neurological responses, including crying and leg movements, halting the procedure. This incident triggered a federal investigation by the US Department of Health and Human Services on 21/7, raising questions about brain death criteria.

Globally, countries have varying approaches to determining brain death, balancing clinical speed and reliability with patient safety and objective evidence.

The US: brain death equals legal death

Since 1981, the US Uniform Determination of Death Act (UDDA) has defined brain death as the irreversible cessation of all brain functions, including the brainstem. The American Academy of Neurology's guidelines require three factors: irreversible coma, loss of all brainstem reflexes, and apnea. Supplementary tests like electroencephalograms (EEGs) or cerebral angiography are options when clinical evaluations are inconclusive. However, clinical assessment remains the primary method.

The Hoover case highlighted potential flaws in this process, as neurological signs appeared despite the brain death declaration.

The UK: focus on the brainstem

The UK focuses on brainstem function. Since 2008, the UK Department of Health's guidelines for brainstem death diagnosis mandate clinical examinations by at least two independent doctors uninvolved in transplantation. These examinations involve assessing light, swallowing, and pain reflexes, along with apnea testing. Imaging tests are reserved for situations where clinical assessment is impossible.

In the UK, irreversible brainstem function loss constitutes death, even if minimal cortical activity persists in some tests, contrasting with the US whole-brain death definition. This simplified process allows for quicker determinations but has sparked legal disputes concerning the right to withdraw life support, particularly when imaging isn't mandatory.

The 2022 case of 12-year-old Archie Battersbee, declared brain dead at the Royal London Hospital after a suicide attempt, fueled national debate. Despite doctors confirming brainstem death, his family contested the diagnosis and refused to allow life support withdrawal, leading to legal battles over parental rights, brain death criteria, and end-of-life care decisions. The court ultimately ruled in favor of life support withdrawal, resulting in his death in August of that year.

Life support monitor in a hospital. *Photo: Pexel*

Japan: requiring consent for organ donation

Japan mandates both medical diagnosis and consent for organ donation to declare brain death. Without prior intent or family consent, doctors won't declare brain death, even if medically qualified. Japan employs stringent criteria, requiring EEGs, cerebral blood flow measurements, and extensive clinical evaluations over several hours, with at least a 6-hour interval between tests to minimize errors. This approach prioritizes ethical considerations and community beliefs in a society where organ donation remains culturally and religiously sensitive.

China: national standards with mandatory consultation

In 2013, China implemented a six-step national standard for determining brain death. First, doctors must identify the cause of brain injury and rule out reversible factors like hypothermia or drug poisoning. Then, they conduct clinical evaluations and apnea tests to confirm the loss of brainstem reflexes and spontaneous breathing. The next step involves at least two of three supporting tests: EEG, somatosensory evoked potentials (SEPs), and transcranial Doppler ultrasound (TCD). The entire process is repeated after a minimum of 12 hours, requiring consultation with at least three independent doctors. Brain death is declared only with unanimous agreement.

While this rigorous system has minimized brain death misdiagnosis, it has oversight vulnerabilities. A 2020 scandal in Anhui province saw six individuals, including four doctors, imprisoned for illegally harvesting organs from 11 patients believed to have been legally donated. They falsified documents and removed bodies for organ retrieval, selling the organs to other hospitals. The scheme was uncovered when a victim's son found no record of the consent form.

The varying approaches to determining brain death globally reflect medical advancements, legal frameworks, and ethical perspectives on life and death. "Brain death is a medical concept with legal implications," notes Dr. Robert Truog, Director of the Center for Bioethics at Harvard University. "When the line between life and death blurs, utmost caution is essential." In the US, following controversial cases, legislators are pursuing reforms in organ distribution networks, including reevaluating brain death criteria.

Thuc Linh (*Guardian, Washington Post, BBC, Harvard*)