You'd think that there would be a certain set of definitive standards followed by all health care centers in diagnosing brain-death. You'd be wrong.
In some cases, hospitals do not require doctors to follow protocols that would rule out conditions that mimic brain death but that can be improved with proper treatment. In other cases, hospitals adopted cumbersome procedures that delay the proper diagnosis of brain death, putting patients in need of donor organs at risk, according to a report published Monday in the journal JAMA Neurology.
If you've gone hypothermic after falling into cold water and being subsequently fished out, you might actually have a decent shot at recovery - if you're not declared brain-dead first; nearly two-thirds of hospitals do not require doctors to be certain that your core body temperature has returned to something close to normal before pronouncing you brain-dead.
As it happens, there are standards for making the determination - it's just that a majority of hospitals in the USA haven't adopted them. Apparently they prefer the time-honored tradition of waiting for the insurance money to run out and then unplugging you.