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The skydiver who had a close shave with death
How likely is it that someone who has had a cardiac arrest will be successfully resuscitated?
Large studies of people with cardiac arrest show that if they are treated within a window of about 5 minutes, we can keep 50 per cent of those people alive. After 15 minutes, that drops to 1 per cent or less. My aim is to make it as likely that people will survive after 15 minutes as after 5. There are a number of things we could do to make this happen: for example, better CPR as well as earlier and faster defibrillation. Is there anything more fundamental you can do?
Death is an active process. After 15 minutes, many of our cells give off complicated biochemical signals that trigger their selfdestruction, so one thing we can figure out is how to undo this death message. I think that’s something we can do chemically. Cooling the body can protect the cells, although nobody knows how, so learning how to do this more quickly will be important. We’re also trying to develop other therapies that will allow us to communicate better with cells. So the death message causes the cell to shut down?
It’s more than that – some cells blow up. The intense reintroduction of oxygen to oxygenstarved cells makes some cells actively explode. It is a program, like the Star Trek self-destruct sequence, and we’ve only just begun to learn about it. Other cells respond by quietly committing suicide. When cells die, they don’t just run out of gas, they flip a series of switches that set off a self-destruct sequence and each cell kills itself in a very active and intentional way. www.newscientist.com
What provokes the death message?
I’m dead! Bye!
There are competing chemical pathways in cells. We normally live with a few death signals and a few life signals that usually stay in balance. When the blood flow stops – a process called ischaemia – the death signals start to increase. The life signals try to keep up, but we’ve learned that the way we restore oxygen when we restart blood flow actually flips the balance so the death signals dominate.
New Zealand skydiver Michael Holmes had a close shave last year I was about 370 metres up when my main parachute failed. I wasn’t that worried at first. It was only when I had done all I could do that mild panic set in, and at around 170 metres from the ground I realised my time really was up. I shouted into the helmet camera we’d been using to video the whole experience, “Oh shit, I’m dead! Bye!” I was frightened, but not overwhelmingly so. I even remember accepting that I was going to die, and from then on everything seemed peaceful. I hit the ground at around 35 metres per second, so really I should have died. I survived because some blackberry bushes cushioned my fall. That and the fact that I came down in a sweeping motion rather than making a vertical hit. I was out cold for a few minutes, but came out of it with only a broken ankle and punctured lung. I realise that I was super-lucky, but the experience hasn’t changed my life that much. I still skydive. I never thought for a second after the accident that I’d give up skydiving. If I could choose how to die it would probably be in my sleep. I wouldn’t see it coming – unlike what almost happened to me that day.
So giving oxygen in resuscitation is actually a bad thing?
Giving oxygen can be a double-edged sword. You’ve got to have oxygen, but it has some positive effects and some negative effects. It was a big surprise when we first learned this. We grew cardiac cells that actually started to beat, and then we took their oxygen away. They stopped beating and just sat there. They didn’t look too healthy but they didn’t look dead. Then we gave the cells back their normal oxygen and under the intense conditions of reperfusion, they suddenly exploded. We wrote it up and sent it to a journal, but they rejected it immediately, saying it couldn’t be true. So we did more tests and were eventually able to publish our findings. It sparked our whole line of research into what we call reperfusion injury – the idea that giving the cells oxygen can kill them.
Ashes to art
How can you improve that situation?
It may come down to new drugs and devices, as well as figuring out where exactly the death signals are coming from and somehow stopping them. I think of the cell as being booby-trapped for death and there’s actually an important reason for this. There are cells all the time that we have to kill off – old cells that aren’t working too well, malignant cells that we don’t want to grow into a cancer, infected cells that we don’t want infecting the rest of the body. There’s no way to have multicellular life without having very active death pathways. So we think that after ischaemia there’s a response that tells more cells to die. If we can temporarily put that on hold, we can make significant headway.
London artist Jason Shulman’s unusual memorial to his father
How can you stop cells dying after ischaemia?
We can work on how we give oxygen and we can learn more about how mitochondria handle oxygen. A point of real surprise for me was when many indicators started to point to mitochondria as being not the organelles of energy, as I thought they were, but the organelles that control death. Many of us grew up thinking that mitochondria provide energy for the cell, but it turns
A PIECE OF MY FATHER BY JASON SHULMAN, 2004
with reasonable advanced therapies, then as a clinician I would say: I don’t know what their brain function is but their heart has not beat for an hour and I’ve been doing CPR (cardiopulmonary resuscitation), I’ve been giving them epinephrine, I’ve been shocking them, I’ve been doing all the things our current techniques tell me to do and it hasn’t worked. This heart is not going to restart and I can pronounce them dead. There are also people who we pronounce dead with their heart still beating. Those are people who we believe to have “irreversible” brain injury. We call that brain death, whatever that might be, but we know that our current techniques won’t get them back. Those are the two major criteria we would use to pronounce someone dead and I would suggest that both of them will undergo modification and alteration as we develop new techniques and prove that something we thought was irreversible is actually reversible.
Though there is no God – dead is dead, dust to dust – there are ways to give someone continuity after death. You can build a pyramid, plant a rose or shoot them into space. But for me few of these address the wonder of life. The idea of how I would commemorate my father came to me when I collected his ashes, which at first sight looked like fire-grate ashes, dead and grey. I extracted the iron using a magnet and noticed tiny bits of colour – red, yellow and green oxidised bone. I sifted out these coloured fragments and stratified them in a 20-centimetre glass tube, with the iron at the top. The tube is suspended by a large magnet above that attracts the iron fragments and by a thread below connected to the ground. The artwork fights natural forces – gravity and magnetism – and has its own mortality: the slightest disturbance and it would fall to the ground. There were difficult moments. I found a gallstone and a tooth filling: things I recognised as having been part of my father.
13 October 2007 | NewScientist | 51
Large studies of people with cardiac arrest show that if they are treated within a window of about 5 minutes, we can keep 50 per cent of those people alive. After 15 minutes, that drops to 1 per cent or less. My aim is to make it as likely that people will survive after 15 minutes as after 5. There are a number of things we could do to make this happen: for example, better CPR as well as earlier and faster defibrillation. Is there anything more fundamental you can do?
Death is an active process. After 15 minutes, many of our cells give off complicated biochemical signals that trigger their selfdestruction, so one thing we can figure out is how to undo this death message. I think that’s something we can do chemically. Cooling the body can protect the cells, although nobody knows how, so learning how to do this more quickly will be important. We’re also trying to develop other therapies that will allow us to communicate better with cells. So the death message causes the cell to shut down?
It’s more than that – some cells blow up. The intense reintroduction of oxygen to oxygenstarved cells makes some cells actively explode. It is a program, like the Star Trek self-destruct sequence, and we’ve only just begun to learn about it. Other cells respond by quietly committing suicide. When cells die, they don’t just run out of gas, they flip a series of switches that set off a self-destruct sequence and each cell kills itself in a very active and intentional way. www.newscientist.com
What provokes the death message?
I’m dead! Bye!
There are competing chemical pathways in cells. We normally live with a few death signals and a few life signals that usually stay in balance. When the blood flow stops – a process called ischaemia – the death signals start to increase. The life signals try to keep up, but we’ve learned that the way we restore oxygen when we restart blood flow actually flips the balance so the death signals dominate.
New Zealand skydiver Michael Holmes had a close shave last year I was about 370 metres up when my main parachute failed. I wasn’t that worried at first. It was only when I had done all I could do that mild panic set in, and at around 170 metres from the ground I realised my time really was up. I shouted into the helmet camera we’d been using to video the whole experience, “Oh shit, I’m dead! Bye!” I was frightened, but not overwhelmingly so. I even remember accepting that I was going to die, and from then on everything seemed peaceful. I hit the ground at around 35 metres per second, so really I should have died. I survived because some blackberry bushes cushioned my fall. That and the fact that I came down in a sweeping motion rather than making a vertical hit. I was out cold for a few minutes, but came out of it with only a broken ankle and punctured lung. I realise that I was super-lucky, but the experience hasn’t changed my life that much. I still skydive. I never thought for a second after the accident that I’d give up skydiving. If I could choose how to die it would probably be in my sleep. I wouldn’t see it coming – unlike what almost happened to me that day.
So giving oxygen in resuscitation is actually a bad thing?
Giving oxygen can be a double-edged sword. You’ve got to have oxygen, but it has some positive effects and some negative effects. It was a big surprise when we first learned this. We grew cardiac cells that actually started to beat, and then we took their oxygen away. They stopped beating and just sat there. They didn’t look too healthy but they didn’t look dead. Then we gave the cells back their normal oxygen and under the intense conditions of reperfusion, they suddenly exploded. We wrote it up and sent it to a journal, but they rejected it immediately, saying it couldn’t be true. So we did more tests and were eventually able to publish our findings. It sparked our whole line of research into what we call reperfusion injury – the idea that giving the cells oxygen can kill them.
Ashes to art
How can you improve that situation?
It may come down to new drugs and devices, as well as figuring out where exactly the death signals are coming from and somehow stopping them. I think of the cell as being booby-trapped for death and there’s actually an important reason for this. There are cells all the time that we have to kill off – old cells that aren’t working too well, malignant cells that we don’t want to grow into a cancer, infected cells that we don’t want infecting the rest of the body. There’s no way to have multicellular life without having very active death pathways. So we think that after ischaemia there’s a response that tells more cells to die. If we can temporarily put that on hold, we can make significant headway.
London artist Jason Shulman’s unusual memorial to his father
How can you stop cells dying after ischaemia?
We can work on how we give oxygen and we can learn more about how mitochondria handle oxygen. A point of real surprise for me was when many indicators started to point to mitochondria as being not the organelles of energy, as I thought they were, but the organelles that control death. Many of us grew up thinking that mitochondria provide energy for the cell, but it turns
A PIECE OF MY FATHER BY JASON SHULMAN, 2004
with reasonable advanced therapies, then as a clinician I would say: I don’t know what their brain function is but their heart has not beat for an hour and I’ve been doing CPR (cardiopulmonary resuscitation), I’ve been giving them epinephrine, I’ve been shocking them, I’ve been doing all the things our current techniques tell me to do and it hasn’t worked. This heart is not going to restart and I can pronounce them dead. There are also people who we pronounce dead with their heart still beating. Those are people who we believe to have “irreversible” brain injury. We call that brain death, whatever that might be, but we know that our current techniques won’t get them back. Those are the two major criteria we would use to pronounce someone dead and I would suggest that both of them will undergo modification and alteration as we develop new techniques and prove that something we thought was irreversible is actually reversible.
Though there is no God – dead is dead, dust to dust – there are ways to give someone continuity after death. You can build a pyramid, plant a rose or shoot them into space. But for me few of these address the wonder of life. The idea of how I would commemorate my father came to me when I collected his ashes, which at first sight looked like fire-grate ashes, dead and grey. I extracted the iron using a magnet and noticed tiny bits of colour – red, yellow and green oxidised bone. I sifted out these coloured fragments and stratified them in a 20-centimetre glass tube, with the iron at the top. The tube is suspended by a large magnet above that attracts the iron fragments and by a thread below connected to the ground. The artwork fights natural forces – gravity and magnetism – and has its own mortality: the slightest disturbance and it would fall to the ground. There were difficult moments. I found a gallstone and a tooth filling: things I recognised as having been part of my father.
13 October 2007 | NewScientist | 51