What is it like to die?
Some people who have been revived say they saw a light at the end of a tunnel. Some report sights of demons with pitchforks or a featureless void that goes on forever in time and space. Others describe leaving their body and watching doctors work on them. “Your consciousness, part of what makes you who you are, does not get annihilated when you go through death,” says Sam Parnia, who has studied near-death experiences. “It remains, but we’re not sure for how long.”
However, Parnia might soon uncover new clues about what happens in the brain as life ebbs. He and colleagues are developing techniques that could significantly improve the success rate of cardiopulmonary resuscitation, better known as CPR.
Cardiac arrest was almost always fatal until CPR was introduced in the 1960s. Chest compressions, often combined with artificial ventilation, could be used to help restore blood flow, and hence oxygen, to the brain and other organs. The technique, which can be performed both by doctors and laypeople, would buy time before a defibrillator was available to give the heart an electric shock and restore its natural rhythm. Suddenly, resuscitation became a possibility, with success cases reported all over the world.
Nonetheless, the odds of being revived are still low. There are about 350,000 resuscitation attempts outside hospitals in the U.S. every year, but about 12 percent of people survive. Almost 40 percent of cardiac arrests happen in a hospital, but even there around one in four people survive. CPR is “not very effective,” says Parnia, a leading resuscitation researcher at New York University Langone Medical Center.
He and his colleagues are trying to make the biggest improvements in CPR since it was conceived over 50 years ago. They’re focusing on how to keep the brain intact.
Rebooting a person’s heart is only part of the CPR puzzle. By the time the heart begins to beat again, the brain might have been deprived of too much oxygen for too long. A person could come back to life with brain damage or in a vegetative state. But Parnia and his colleagues have now figured out how much oxygen needs to be maintained in the brain to lessen the chance of those problems.
“There is a high divorce rate among people who have had a near-death experience.”
They have also found a way to monitor those oxygen levels in real time during CPR using a non-invasive technique that shines infrared light into a patient’s brain. In a recent study, they showed that it can be combined with EEG, a way of measuring brainwaves by placing electrodes on the scalp, to reveal the corresponding brain activity and gain insight into how the brain is functioning.
Their next step is to figure out how to deliver more oxygen to the brain during CPR. For the cases that occur in hospitals, existing technologies that aren’t widely used could be part of the solution. For example, there’s extra corporeal membrane oxygenation, or ECMO, a procedure used for life support. It involves pumping blood out of a cardiac arrest patient and into a machine where it is oxygenated and recirculated into the body. Another possible alternative is to increase use of mechanical CPR. That’s when doctors strap a device onto a patient to provide more consistent and uninterrupted chest compressions. “Both have been shown to increase oxygen delivery to the brain,” says Parnia.
If the researchers are successful, surviving a cardiac arrest will become much more common. And the more people we resurrect, the better we will understand the process of death.
Because of the spooky nature of near-death experiences, for instance, it’s often suggested that something paranormal is going on as life ends. People recount floating above their bodies and watching their own resuscitation, hinting that we possess a soul that separates from our physical self. Experiments have attempted to verify these claims by placing hidden targets in hospital rooms that are only visible from above. However so far nobody has reported seeing them during an out-of-body experience.
Christopher French, a psychologist from Goldsmiths, University of London who studies paranormal experiences, thinks that conventional neuroscience will be able to explain near-death accounts. Fighter pilots have reported similar visions when they have lost consciousness during extreme acceleration, which also causes reduced blood flow and hence oxygen to the brain. And some people are able to have out-of-body experiences at will. Evidence from these cases suggests that it’s a type of hallucination that occurs when sensory inputs such as proprioception, vision, and hearing aren’t properly perceived by the brain. But further research is needed to thoroughly explain near-death experiences. “It’s a hard topic to study due to ethical constraints,” says French. “Technological developments will probably allow us to get a greater insight.”
Having more resurrected flatliners among us could prompt more people to reevaluate what’s important in life.
A greater familiarity with near-death experiences may also help to support those who have survived them. Especially in Western cultures, people can find it hard to talk about what they have seen because there is still no accepted scientific rationale and they fear seeming crazy. This can make it hard for them to connect with people they used to be close to. “There is a high divorce rate among people who have had a near-death experience,” says French.
Feeling alienated may be less of an issue in a world where more people are resuscitated and report similar accounts. “People might feel safer talking about them,” says Natasha Tassell-Matamua, a psychology researcher at Massey University in New Zealand. At the moment, she thinks, there are a lot of unreported cases.
All in all, near-death experiences are positive for most people. They interpret what they’ve seen as glimpses of an afterlife. It tends to make them less scared of dying, more caring, and more spiritual. “It’s a long-lasting effect,” French says.
Perhaps they can influence the rest of us as well. Tassell-Matamua found that when people were taught about near-death experiences and their aftereffects, they reaped some of the same benefits as survivors, such as a better appreciation of life, death, and spirituality. “It’s all too easy on a day-to-day basis to be engrossed in a to-do list of trivial jobs,” says French, who thinks that having more resurrected flatliners among us could prompt more people to reevaluate what’s important in life.