Harvesting the organs of a living person is generally considered morally reprehensible, but the aversion tends to fade when the person in question no longer has a functioning brain or any hope of recovery. A new Yale study has found that the legal boundary separating these two scenarios is far from consistent across international borders.

“The issue is that extermination of life by neurological criteria — brain death — is extremely hard to grasp, even when it is defined by law and there are reliable procedures for determining it,” said Nancy Berlinger, research scholar for the Hastings Center, a bioethics research ormal color.”

Because of that, even in places where the legal and procedural boundaries are clear, there can be uncertainty in determining whether death has occurred, and thus whether physicians can move forward with organ transplants, the study found.

Across 91 countries and six continents, physicians were surveyed on whether they knew about the existence of laws establishing brain death, and whether they had institutional procedures to address the condition. The study also examined the way doctors perceived, interacted and evaluated — using gag reflexes and pupil response tests, for instance — brain-dead patients.

The researchers found that there is drastically greater legal and procedural focus on brain damage in richer countries than in poorer countries. In fact, only two of nine poor countries reported the existence of legal procedures, while all but one of the 36 rich countries did.

“In order to get to a determination of brain death, you need to have had the most advanced sort of life-sustaining technology supporting the heart and lung to even figure out if brain death has occurred,” said Berlinger.

She added that if a country does not have highly advanced life-support technology — as is the case for many poor countries — bodies will expire before brain death criteria can be evaluated.

It is the presence of expensive and advanced medical technology in intensive care units that keeps people alive up to the point that they can become brain dead, said David Greer, Yale professor of neurology and co-author of the study. And because of the medical technology, clearer definitions of brain death are needed.

“In a country in Africa, odds are that the only way for a patient’s organs to be maintained would be to take turns hand-operating a mask and a bag,” said Greer. “And that’s not feasible.”

Similarly, the study found that when a country had a better-established transplant network — facilitating the transfer of a brain-dead person’s liver, for instance, to someone in need — that country was more likely to have established laws regarding brain-dead patients.

Berlinger said that this trend was likely because the existence of organ transplant infrastructure made it particularly critical to understand brain death, which is a prerequisite to donating certain organs. Organ transplant infrastructures were much more common in richer countries.

However, not all criteria and procedures for brain death increased with wealth. In fact, the study found that only 47 percent of countries surveyed had procedures for establishing brain death similar to the American Academy of Neurology’s definition. The 53 percent who had procedures different in some manner from the American Academy of Neurology’s criteria were not significantly concentrated in any level of wealth.

Because many countries, even wealthy countries, lack procedures similar to the American Academy of Neurology’s criteria, Greer thinks that in some countries, it is more likely that someone may be declared brain dead when they are, in fact, alive.

“Let’s say they don’t require that the pupil response be absent, or the gag reflex be absent,” said Greer. “Those are things that measure brain functioning at a very rudimentary level, so unless those are accounted for, physicians may be misdiagnosing people, which would be the worst thing possible.”

The misdiagnosed patients would almost certainly not be recoverable already, said Greer, but could still have brain-functioning capacity. Misdiagnosis, then, crosses a “very clear line” by cutting off support for the patient before he or she is actually dead.

“This is something where you need to be 100 percent certain,” said Greer.