“Coming Back from the Dead” Is No Longer Science Fiction
Last year, there were widespread reports of a 53-year-old Frenchman who had suffered a cardiac arrest and "died," but was then resuscitated back to life 18 hours after his heart had stopped.
The once black-and-white line between life and death is now blurrier than ever.
This was thought to have been possible in part because his body had progressively cooled down naturally after his heart had stopped, through exposure to the outside cold. The medical team who revived him were reported as being "stupefied" that they had been able to bring him back to life, in particular since he had not even suffered brain damage.
Interestingly, this man represents one of a growing number of extraordinary cases in which people who would otherwise be declared dead have now been revived. It is a testament to the incredible impact of resuscitation science -- a science that is providing opportunities to literally reverse death, and in doing so, shedding light on the age-old question of what happens when we die.
Death: Past and Present
Throughout history, the boundary between life and death was marked by the moment a person's heart stopped, breathing ceased, and brain function shut down. A person became motionless, lifeless, and was deemed irreversibly dead. This is because once the heart stops beating, blood flow stops and oxygen is cut off from all the body's organs, including the brain. Consequently, within seconds, breathing stops and brain activity comes to a halt. Since the cessation of the heart literally occurs in a "moment," the philosophical notion of a specific point in time of "irreversible" death still pervades society today. The law, for example, relies on "time of death," which corresponds to when the heart stops beating.
The advent of cardiopulmonary resuscitation (CPR) in the 1960s was revolutionary, demonstrating that the heart could potentially be restarted after it had stopped, and what had been a clear black-and-white line was shown to be potentially reversible in some people. What was once called death—the ultimate end point— was now widely called cardiac arrest, and became a starting point.
From then on, it was only if somebody had requested not to be resuscitated or when CPR was deemed to have failed that people would be declared dead by "cardiopulmonary criteria." Biologically, cardiac arrest and death by cardiopulmonary criteria are the same process, albeit marked at different points in time depending on when a declaration of death is made.
The apparent irreversibility of death as we know it may not necessarily reflect true irretrievable cellular damage inside the body.
Clearly, contrary to many people's perceptions, cardiac arrest is not a heart attack; it is the final step in death irrespective of cause, whether it be a stroke, a heart attack, a car accident, an overwhelming infection or cancer. This is how roughly 95 percent of the population are declared dead.
The only exception is the small proportion of people who may have suffered catastrophic brain injuries, but whose hearts can be artificially kept beating for a period of time on life-support machines. These people can be legally declared dead based on brain death criteria before their hearts have stopped. This is because the brain can die either from oxygen starvation after cardiac arrest or from massive trauma and internal bleeding. Either way, the brain dies hours or possibly longer after these injuries have taken place and not just minutes.
A Profound Realization
What has become increasingly clear is that the apparent irreversibility of death as we know it may not necessarily reflect true irretrievable cellular damage inside the body. This is consistent with a mounting understanding: it is only after a person actually dies that the cells in the body start to undergo their own process of death. Intriguingly, this process is something that can now be manipulated through medical intervention. Being cold is one of the factors that slows down the rate of cellular decay. The 53-year-old Frenchman's case and the other recent cases of resuscitation after prolonged periods of time illustrate this new understanding.
Last week's earth-shattering announcement by neuroscientist Dr. Nenad Sestan and his team out of Yale, published in the prestigious scientific journal Nature, provides further evidence that a time gap exists between actual death and cellular death in cadavers. In this seminal study, these researchers were able to restore partial function in pig brains four hours after their heads were severed from their bodies. These results follow from the pioneering work in 2001 of geneticist Fred Gage and colleagues from the Salk Institute, also published in Nature, which demonstrated the possibility of growing human brain cells in the laboratory by taking brain biopsies from cadavers in the mortuary up to 21 hours post-mortem.
The once black-and-white line between life and death is now blurrier than ever. Some people may argue this means these humans and pigs weren't truly "dead." However, that is like saying the people who were guillotined during the French Revolution were also not dead. Clearly, that is not the case. They were all dead. The problem is not death; it's our reliance on an outdated philosophical, rather than biological, notion of death.
Death can no longer be considered an absolute moment but rather a process that can be reversed even many hours after it has taken place.
But the distinction between irreversibility from a medical perspective and biological irreversibility may not matter much from a pragmatic perspective today. If medical interventions do not exist at any given time or place, then of course death cannot be reversed.
However, it is crucial to distinguish between biologically and medically: When "irreversible" loss of function arises due to inadequate treatment, then a person could be potentially brought back in the future when an alternative therapy becomes available, or even today if he or she dies in a location where novel treatments can slow down the rate of cell death. However, when true irreversible loss of function arises from a biological perspective, then no treatment will ever be able to reverse the process, whether today, tomorrow, or in a hundred years.
Probing the "Grey Zone"
Today, thanks to modern resuscitation science, death can no longer be considered an absolute moment but rather a process that can be reversed even many hours after it has taken place. How many hours? We don't really know.
One of the wider implications of our medical advances is that we can now study what happens to the human mind and consciousness after people enter the "grey zone," which marks the time after the heart stops, but before irreversible and irretrievable cell damage occurs, and people are then brought back to life. Millions have been successfully revived and many have reported experiencing a unique, universal, and transformative mental state.
Were they "dead"? Yes, according to all the criteria we have ever used. But they were able to be brought back before their "dead" bodies had reached the point of permanent, irreversible cellular damage. This reflects the period of death for all of us. So rather than a "near-death experience," I prefer a new terminology to describe these cases -- "an actual-death experience." These survivors' unique experiences are providing eyewitness testimonies of what we will all be likely to experience when we die.
Such an experience reportedly includes seeing a warm light, the presence of a compassionate perfect individual, deceased relatives, a review of their lives, a judgment of their actions and intentions as they pertain to their humanity, and in some cases a sensation of seeing doctors and nurses working to resuscitate them.
Are these experiences compatible with hallucinations or illusions? No -- in part, because these people have described real, verifiable events, which, by definition are not hallucinations, and in part, because their experiences are not compatible with confused and delirious memories that characterize oxygen deprivation.
The challenge for us scientifically is understanding how this is possible at a time when all our science tells us the brain shuts down.
For instance, it is hard to classify a structured meaningful review of one's life and one's humanity as hallucinatory or illusory. Instead, these experiences represent a new understanding of the overall human experience of death. As an intensive care unit physician for more than 10 years, I have seen numerous cases where these reports have been corroborated by my colleagues. In short, these survivors have been known to come back with reports of full consciousness, with lucid, well-structured thought processes and memory formation.
The challenge for us scientifically is understanding how this is possible at a time when all our science tells us the brain shuts down. The fact that these experiences occur is a paradox and suggests the undiscovered entity we call the "self," "consciousness," or "psyche" – the thing that makes us who we are - may not become annihilated at the point of so-called death.
At New York University, the State University of New York, and across 20 hospitals in the U.S. and Europe, we have brought together a new multi-disciplinary team of experts across many specialties, including neurology, cardiology, and intensive care. Together, we hope to improve cardiac arrest prevention and treatment, as well as to address the impact of new scientific discoveries on our understanding of what happens at death.
One of our first studies, Awareness during Resuscitation (AWARE), published in the medical journal Resuscitation in 2014, confirmed that some cardiac arrest patients report a perception of awareness without recall; others report detailed memories and experiences; and a few report full auditory and visual awareness and consciousness of their experience, from a time when brain function would be expected to have ceased.
While you probably have some opinion or belief about this based upon your own philosophical, religious, or cultural background, you may not realize that exploring what happens when we die is now a subject that science is beginning to investigate.
There is no question more intriguing to humankind. And for the first time in our history, we may finally uncover some real answers.
With a deadly pandemic sweeping the planet, many are questioning the comfort and security we have taken for granted in the modern world.
A century ago, when an influenza pandemic struck, we barely knew what viruses were.
More than a century after the germ theory, we are still at the mercy of a microbe we can neither treat, nor control, nor immunize against. Even more discouraging is that technology has in some ways exacerbated the problem: cars and air travel allow a new disease to quickly encompass the globe.
Some say we have grown complacent, that we falsely assume the triumphs of the past ensure a happy and prosperous future, that we are oblivious to the possibility of unpredictable "black swan" events that could cause our destruction. Some have begun to lose confidence in progress itself, and despair of the future.
But the new coronavirus should not defeat our spirit—if anything, it should spur us to redouble our efforts, both in the science and technology of medicine, and more broadly in the advance of industry. Because the best way to protect ourselves against future disasters is more progress, faster.
Science and technology have overall made us much better able to deal with disease. In the developed world, we have already tamed most categories of infectious disease. Most bacterial infections, such as tuberculosis or bacterial pneumonia, are cured with antibiotics. Waterborne diseases such as cholera are eliminated through sanitation; insect-borne ones such as malaria through pest control. Those that are not contagious until symptoms appear, such as SARS, can be handled through case isolation and contact tracing. For the rest, such as smallpox, polio, and measles, we develop vaccines, given enough time. COVID-19 could start a pandemic only because it fits a narrow category: a new, viral disease that is highly contagious via pre-symptomatic droplet/aerosol transmission, and that has a high mortality rate compared to seasonal influenza.
A century ago, when an influenza pandemic struck, we barely knew what viruses were; no one had ever seen one. Today we know what COVID-19 is down to its exact genome; in fact, we have sequenced thousands of COVID-19 genomes, and can track its history and its spread through their mutations. We can create vaccines faster today, too: where we once developed them in live animals, we now use cell cultures; where we once had to weaken or inactivate the virus itself, we can now produce vaccines based on the virus's proteins. And even though we don't yet have a treatment, the last century-plus of pharmaceutical research has given us a vast catalog of candidate drugs, already proven safe. Even now, over 50 candidate vaccines and almost 100 candidate treatments are in the research pipeline.
It's not just our knowledge that has advanced, but our methods. When smallpox raged in the 1700s, even the idea of calculating a case-fatality rate was an innovation. When the polio vaccine was trialled in the 1950s, the use of placebo-controlled trials was still controversial. The crucial measure of contagiousness, "R0", was not developed in epidemiology until the 1980s. And today, all of these methods are made orders of magnitude faster and more powerful by statistical and data visualization software.
If you're seeking to avoid COVID-19, the hand sanitizer gel you carry in a pocket or purse did not exist until the 1960s. If you start to show symptoms, the pulse oximeter that tests your blood oxygenation was not developed until the 1970s. If your case worsens, the mechanical ventilator that keeps you alive was invented in the 1950s—in fact, no form of artificial respiration was widely available until the "iron lung" used to treat polio patients in the 1930s. Even the modern emergency medical system did not exist until recently: if during the 1918 flu pandemic you became seriously ill, there was no 911 hotline to call, and any ambulance that showed up would likely have been a modified van or hearse, with no equipment or trained staff.
As many of us "shelter in place", we are far more able to communicate and collaborate, to maintain some semblance of normal life, than we ever would have been. To compare again to 1918: long-distance telephone service barely existed at that time, and only about a third of homes in the US even had electricity; now we can videoconference over Zoom and Skype. And the enormous selection and availability provided by online retail and food delivery have kept us stocked and fed, even when we don't want to venture out to the store.
Let the virus push us to redouble our efforts to make scientific, technological, and industrial progress on all fronts.
"Black swan" calamities can strike without warning at any time. Indeed, humanity has always been subject to them—drought and frost, fire and flood, war and plague. But we are better equipped now to deal with them than ever before. And the more progress we make, the better prepared we'll be for the next one. The accumulation of knowledge, technology, industrial infrastructure, and surplus wealth is the best buffer against any shock—whether a viral pandemic, a nuclear war, or an asteroid impact. In fact, the more worried we are about future crises, the more energetically we should accelerate science, technology and industry.
In this sense, we have grown complacent. We take the modern world for granted, so much so that some question whether further progress is even still needed. The new virus proves how much we do need it, and how far we still have to go. Imagine how different things would be if we had broad-spectrum antiviral drugs, or a way to enhance the immune system to react faster to infection, or a way to detect infection even before symptoms appear. These technologies may seem to belong to a Star Trek future—but so, at one time, did cell phones.
The virus reminds us that nature is indifferent to us, leaving us to fend entirely for ourselves. As we go to war against it, let us not take the need for such a war as reason for despair. Instead, let it push us to redouble our efforts to make scientific, technological, and industrial progress on all fronts. No matter the odds, applied intelligence is our best weapon against disaster.
With millions of people left feeling helpless as COVID-19 sweeps across the U.S. and the rest of the planet, there is one way in which absolutely anyone can help fight the pandemic -- all you need is a computer and an Internet connection.
"The more donors that participate, the more science we're able to do."
The Folding@home project allows members of the public to contribute a portion of their computing power to a gigantic virtual network which has mushroomed over the past month to become the most powerful supercomputer on the planet.
As of April 6, more than one million people across the globe have donated some of their home computing resources to the project. Combined, this gives Folding@home processing powers that dwarf even NASA and IBM's most powerful devices. To join, all you have to do is go to this website and click 'Download Now' to load the Folding@home software on your computer. This runs in the background, and only adds your unused computing power to the project, so it will not drain resources from tasks you're trying to do.
"It's totally crazy," said Vincent Voelz, associate professor of chemistry at Temple University, Philadelphia, and one of the scientists leading the project. "A month ago, we had around 30,000 to 40,000 participants. And then last week, it rose up 400,000 and now we've hit a million. But the more donors that participate, the more science we're able to do."
Voelz and the other scientists behind Folding@home are using these vast resources to model the ever-changing shapes of the coronavirus's proteins, in the hopes of identifying vulnerabilities or 'pockets' in its structure that can be targeted with new drugs.
One of the reasons it's difficult to find treatments for viruses like COVID-19 and Ebola is because the proteins, the innate building blocks of the viral structure, have notoriously smooth surfaces, making it hard for drugs to bind to them.
But viral proteins don't stay still. They are constantly evolving and changing shape as the atoms within push and pull against each other. Having a supercomputer enables scientists to simulate all these different shapes, revealing potential weaknesses which were not immediately visible. And the more powerful the supercomputer, the faster these simulations can happen.
"Simulating these protein motions also enables us to answer basic questions such as what makes this new coronavirus strain different from previous strains," said Voelz. "Is there something about the dynamics of these proteins that makes it more virulent?"
Finding a genuinely novel drug for COVID-19 is particularly critical.
Once they have identified suitable pockets within the proteins of COVID-19, the Folding@home scientists can then take the many compounds being identified by chemists around the world as potential drugs, and try to predict which ones will stand the best chance of binding to those pockets and inhibiting the virus's ability to invade and take over human cells.
"We have so much bandwidth now with Folding@home that we really think we can make a dent with screening these, and prioritizing which compounds are then going to get experimentally tested," said Voeltz.
The team are particularly hopeful they can succeed, having already used the supercomputer to identify a new vulnerability in the Ebola virus, which could go on to yield a new treatment for the disease.
Finding a genuinely novel drug for COVID-19 is particularly critical. While researchers are also looking at repurposing existing medications, like the antimalarials Hydroxychloroquine and Chloroquine (which have just been approved by the FDA for emergency use in coronavirus patients), concerns remain about the safety of these treatments. Researchers at the Mayo Clinic recently warned that the use of these drugs could have the side effect of inducing heart problems and run the risk of sudden cardiac arrest.
But with the death toll increasing by the day, speed is of the essence. Voelz explains that the scientific community has been left playing catch-up, because a drug was never actually developed for the original SARS outbreak in the early 2000s. The enormous computational power of the Folding@home project has the potential to allow scientists to quickly answer some of the key questions needed to get a new treatment into the pipeline.
"We don't have a SARS drug for whatever reason," said Voelz. "So the missing ingredient really, is the basic science to reveal possible drug targets and then the pharma can take that information and do the engineering work and optimizing and clinically testing drugs. But we now have a lot of basic science going on in response to this pandemic."