Death is no longer an event, but a process

Sunday - November 19 2023, 07:21 UTC - 1 year ago

Just as birth certificates mark time of entrance, death certificates mark time of exit. However, evidence of this practice not really grounded in biology reflects an outdated social construct. Scientists and doctors have already embraced the more nuanced understanding of death as a process that could be reversible if medical intervention is done in time. Society needs to rethink how it considers life and death and treat death as a process to save many lives.

Just as birth certificates note the time we enter the world, death certificates mark the moment we exit it. This practice reflects traditional notions about life and death as binaries. We are here until, suddenly, like a light switched off, we are gone.But while this idea of death is pervasive, evidence is building that it is an outdated social construct, not really grounded in biology. Dying is in fact a process—one with no clear point demarcating the threshold across which someone cannot come back .

Scientists and many doctors have already embraced this more nuanced understanding of death. As society catches up, the implications for the living could be profound. "There is potential for many people to be revived again," says Sam Parnia, director of critical care and resuscitation research at NYU Langone Health.Neuroscientists, for example, are learning that the brain can survive surprising levels of oxygen deprivation .

This means the window of time that doctors have to reverse the death process could someday be extended. Other organs likewise seem to be recoverable for much longer than is reflected in current medical practice, opening up possibilities for expanding the availability of organ donations.To do so, though, we need to reconsider how we conceive of and approach life and death. Rather than thinking of death as an event from which one cannot recover, Parnia says, we should instead view it as a transient process of oxygen deprivation that has the potential to become irreversible if enough time passes or medical interventions fail .

If we adopt this mindset about death, Parnia says, "then suddenly, everyone will say, ‘Let’s treat it.’"Moving goalpostsLegal and biological definitions of death typically refer to the "irreversible cessation" of life-sustaining processes supported by the heart, lungs, and brain. The heart is the most common point of failure, and for the vast majority of human history, when it stopped there was generally no coming back .

That changed around 1960, with the invention of CPR. Until then, resuming a stalled heartbeat had largely been considered the stuff of miracles; now, it was within the grasp of modern medicine. CPR forced the first major rethink of death as a concept. "Cardiac arrest" entered the lexicon, creating a clear semantic separation between the temporary loss of heart function and the permanent cessation of life .

Around the same time, the advent of positive-pressure mechanical ventilators, which work by delivering breaths of air to the lungs, began allowing people who incurred catastrophic brain injury—for example, from a shot to the head, a massive stroke, or a car accident—to continue breathing. In autopsies after these patients died, however, researchers discovered that in some cases their brains had been so severely damaged that the tissue had begun to liquefy .

In such cases, ventilators had essentially created "a beating-heart cadaver," says Christof Koch, a neuroscientist at the Allen Institute in Seattle.These observations led to the concept of brain death and ushered in medical, ethical, and legal debate about the ability to declare such patients dead. Recently, technologies including extracorporeal membrane oxygenation (ECMO)—a complex system of pulmonary and cardiac bypass machines—have pushed the boundaries even farther .

ECMO was first widely deployed in the 1970s to treat babies with respiratory distress but can today also be used on adults suffering from cardiogenic shock or even cardiac arrest. It can keep a person’s blood flowing and body warm, and with sufficient oxygenation can prevent brain injury, issuing a kind of suspended animation."ECMO can almost meet any legal definition of life," Parnia says.Reversing the process of dying—which Parnia terms "Away from death"—is a process in which the patient requires extensive medical treatment and intensely aggressive resuscitation and long-term care .

Projects such as Preserving Life are attempting to deploy technology to transform the concept of death as a process."We need to distinguish between those people who are sick and will die, versus those people who are at risk of being declared dead but for whom death is probably not irreversible," Parnia says. "That’s why we have to look at death from both a medical and a social perspective." .