杏吧原创

Are the people you resuscitate after cardiac arrest really dead? Isn鈥檛 the definition of death that it is irreversible?
A cardiac arrest is the same as death. It鈥檚 just semantics. After a gunshot wound, if the person haemorrhages sufficiently, then the heart stops beating and they die. The social perception of death is that you have reached a point from which you can never come back, but medically speaking, death is a biological process. For millennia we have considered someone dead when their heart stops beating.

People often confuse the terms cardiac arrest and heart attack. Clearly, they鈥檙e very different.
A heart attack happens when a clot blocks a blood vessel to the heart. The portion of the heart muscle that was supplied blood and oxygen by that vessel will then die. That鈥檚 why most people with a heart attack don鈥檛 die.

What is the biggest problem in bringing someone back to life?
Reversing death before the person has too much cell damage. People die under many different circumstances and under the watch of many different medical specialists. No single speciality is charged with taking and implementing all the latest advances and technology in resuscitation.

How long after they die can someone still be resuscitated?
People have been resuscitated four or five hours after death 鈥� after basically lying there as a corpse. Once we die the cells in the body undergo their own process of death. After eight hours it鈥檚 impossible to bring the brain cells back.

What is the best way to bring people back?
The ideal system 鈥� and they do this a lot in South-East Asia, Japan and South Korea 鈥� is called ECPR. The E stands for extra corporeal membrane oxygenation (ECMO). It鈥檚 a system in which you take blood from a person who has had a cardiac arrest, and circulate it through a membrane oxygenator, which supplies oxygen and removes carbon dioxide. Then you pump the blood back into circulation around the body. Using ECMO, they have brought people back five to seven hours after they died. ECMO is not routinely available in the US and UK, though.

So, when I go into cardiac arrest, ideally what steps do I want my doctors to take?
First, we start the patient on a machine that provides chest compressions and breathing. Then we attach the patient to a monitor that tells us the quality of oxygen that鈥檚 getting into the brain.

If we do the chest compressions and breathing and give the right drugs and we still can鈥檛 get the oxygen levels to normal, then we go to ECMO. This system can restore normal oxygen levels in the brain and deliver the right amount of oxygen to all the organs to minimise injury.

At the same time you also cool the patient. This slows the rate of metabolic activity in the brain cells to halt the process of cell death while you go and fix the underlying problem.

How do you cool the body?
It used to be ice packs. Today a whole industry has grown up around this, and there are two methods. One is to stick large gel pads onto the torso and the legs. These are attached to a machine that regulates temperature. When the body reaches the right temperature, it keeps it there for 24 hours. The other way is to put a catheter into the groin or neck, and cool the blood down as it passes by the catheter.

Cooling benefits the heart and all the tissues, but we focus on the brain. There are also new methods in which people are cooled through the nose. You put tubes in the nostrils and inject cold vapour to cool the brain down selectively before the rest of the body.

If I had a cardiac arrest today, what are the chances I would get all of that?
Almost zero.

Why isn鈥檛 this type of care routine?
Cardiac arrest is the only medical condition that will affect every single one of us eventually, unfortunately. What鈥檚 frightening is that the way we are managed depends on where we are and who is involved. Even in the same hospital, shift to shift, you will get a different level of care. There is no external regulation, so it鈥檚 left to individuals.

There is disagreement over the interpretation of near death experiences (NDEs) 鈥� such as seeing a tunnel or a bright light. When a person dies, when do these experiences shut off?
One of the last things to fall into the realm of science has been the study of death. And now we have pushed back the boundary of death. In order to ensure that patients come back to life and don鈥檛 have brain damage, we have to study the processes that go on after they die. Whether we like it or not, we have gone into the 鈥渁fterlife鈥� or whatever you want to call it.

For people who have NDEs, they are very real. Most are convinced that what they saw is a glimpse of what it鈥檚 like when we die. Most come back and have no fear of death, and are transformed in a positive way 鈥� becoming more altruistic. As a scientific community we have tried to explain these away, but we haven鈥檛 been successful.

So how can a doctor, or any person of science, deal with such otherworldly experiences?
We have to accept that these experiences occur, that they are real to the people who have them, in the same way that if a patient has depression you would never say, 鈥淚 know that you are feeling depressed but that is just an illusion. I鈥檓 the doctor. I鈥檓 going to tell you what your feelings really mean.鈥� But with NDEs, we do this all the time: 鈥淚 know you think you saw this, but you really didn鈥檛.鈥�

Aren鈥檛 NDEs just hallucinations?
We know from clinical tests that the brain doesn鈥檛 function after death, therefore you can鈥檛 even hallucinate. It鈥檚 ridiculous to say that NDE people are hallucinating because you have to have a functioning brain. If I take a person in cardiac arrest and inject them with LSD, I guarantee you they will not hallucinate.

For your study of out of body experiences (OBEs), you placed images in hospital rooms on high shelves only someone floating near the ceiling could see. So far, two patients have had OBEs, but neither in a room with a shelf鈥�
That鈥檚 right. We had 25 hospitals that had an average of 500 beds working on the study. To put a shelf above every single bed, we would have to put up 12,500 shelves. That was completely unmanageable. We selected areas where cardiac arrest patients are frequently treated but even with that, at least half of those who had cardiac arrests and survived were in areas without shelves.

Are you continuing the experiment?
Yes. It鈥檚 part of an overall package to improve resuscitation to the brain. We are trying not to forget during resuscitation that there鈥檚 a human being in there.

In your book, you imply that death might be pleasant. Why do you think that?
The question is, what happens to human consciousness 鈥� the thing that makes me into who I am 鈥� when my heart stops beating and I die? From our external view, it looks like it simply disappears. But it sort of hibernates, in the same way as it does when you are given a general anaesthetic. And it comes back. I don鈥檛 believe that your consciousness is annihilated when you reach the point of death. How far does it continue? I don鈥檛 know. But I do know that at least in the period of time in which we can bring people back to life that entity of the human mind has not been annihilated.

鈥淐onsciousness is not annihilated when you reach the point of death鈥�

What does this mean?
Those people who have pleasant experiences after death suggest that we should not be afraid of the process. It means there is no reason to fear death.

This article appeared in print under the headline 鈥淩esurrection man鈥�