Old Article, but good info: Truck makers hope for Texas-size sales

From : geekboy

Q: as recently as 1993 when dr. sherwin nuland wrote the best seller how we die the conventional answer was that it was his cells that had died. the patient couldnt be revived because the tissues of his brain and heart had suffered irreversible damage from lack of oxygen. this process was understood to begin after just four or five minutes. if the patient doesnt receive cardiopulmonary resuscitation within that time and if his heart cant be restarted soon thereafter he is unlikely to recover. that dogma went unquestioned until researchers actually looked at oxygen-starved heart cells under a microscope. what they saw amazed them according to dr. lance becker an authority on emergency medicine at the university of pennsylvania. after one hour he says we couldnt see evidence the cells had died. we thought wed done something wrong. in fact cells cut off from their blood supply died only hours later. but if the cells are still alive why cant doctors revive someone who has been dead for an hour because once the cells have been without oxygen for more than five minutes they die when their oxygen supply is resumed. it was that astounding discovery becker says that led him to his post as the director of penns center for resuscitation science a newly created research institute operating on one of medicines newest frontiers treating the dead. biologists are still grappling with the implications of this new view of cell death-not passive extinguishment like a candle flickering out when you cover it with a glass but an active biochemical event triggered by reperfusion the resumption of oxygen supply. the research takes them deep into the machinery of the cell to the tiny membrane-enclosed structures known as mitochondria where cellular fuel is oxidized to provide energy. mitochondria control the process known as apoptosis the programmed death of abnormal cells that is the bodys primary defense against cancer. it looks to us says becker as if the cellular surveillance mechanism cannot tell the difference between a cancer cell and a cell being reperfused with oxygen. something throws the switch that makes the cell die. with this realization came another that standard emergency-room procedure has it exactly backward. when someone collapses on the street of cardiac arrest if hes lucky he will receive immediate cpr maintaining circulation until he can be revived in the hospital. but the rest will have gone 10 or 15 minutes or more without a heartbeat by the time they reach the emergency department. and then what happens we give them oxygen becker says. we jolt the heart with the paddles we pump in epinephrine to force it to beat so its taking up more oxygen. blood-starved heart muscle is suddenly flooded with oxygen precisely the situation that leads to cell death. instead becker says we should aim to reduce oxygen uptake slow metabolism and adjust the blood chemistry for gradual and safe reperfusion. researchers are still working out how best to do this. a study at four hospitals published last year by the university of california showed a remarkable rate of success in treating sudden cardiac arrest with an approach that involved among other things a cardioplegic blood infusion to keep the heart in a state of suspended animation. patients were put on a heart-lung bypass machine to maintain circulation to the brain until the heart could be safely restarted. the study involved just 34 patients but 80 percent of them were discharged from the hospital alive. in one study of traditional methods the figure was about 15 percent. becker also endorses hypothermia-lowering body temperature from 37 to 33 degrees celsius-which appears to slow the chemical reactions touched off by reperfusion. he has developed an injectable slurry of salt and ice to cool the blood quickly that he hopes to make part of the standard emergency-response kit. in an emergency department you work like mad for half an hour on someone whose heart stopped and finally someone says i dont think were going to get this guy back and then you just stop becker says. the body on the cart is dead but its trillions of cells are all still alive. becker wants to resolve that paradox in favor of life. .

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From : napalmheart

as recently as 1993 when dr. sherwin nuland wrote the best seller how we die the conventional answer was that it was his cells that had died. the patient couldnt be revived because the tissues of his brain and heart had suffered irreversible damage from lack of oxygen. this process was understood to begin after just four or five minutes. if the patient doesnt receive cardiopulmonary resuscitation within that time and if his heart cant be restarted soon thereafter he is unlikely to recover. that dogma went unquestioned until researchers actually looked at oxygen-starved heart cells under a microscope. what they saw amazed them according to dr. lance becker an authority on emergency medicine at the university of pennsylvania. after one hour he says we couldnt see evidence the cells had died. we thought wed done something wrong. in fact cells cut off from their blood supply died only hours later. but if the cells are still alive why cant doctors revive someone who has been dead for an hour because once the cells have been without oxygen for more than five minutes they die when their oxygen supply is resumed. it was that astounding discovery becker says that led him to his post as the director of penns center for resuscitation science a newly created research institute operating on one of medicines newest frontiers treating the dead. biologists are still grappling with the implications of this new view of cell death-not passive extinguishment like a candle flickering out when you cover it with a glass but an active biochemical event triggered by reperfusion the resumption of oxygen supply. the research takes them deep into the machinery of the cell to the tiny membrane-enclosed structures known as mitochondria where cellular fuel is oxidized to provide energy. mitochondria control the process known as apoptosis the programmed death of abnormal cells that is the bodys primary defense against cancer. it looks to us says becker as if the cellular surveillance mechanism cannot tell the difference between a cancer cell and a cell being reperfused with oxygen. something throws the switch that makes the cell die. with this realization came another that standard emergency-room procedure has it exactly backward. when someone collapses on the street of cardiac arrest if hes lucky he will receive immediate cpr maintaining circulation until he can be revived in the hospital. but the rest will have gone 10 or 15 minutes or more without a heartbeat by the time they reach the emergency department. and then what happens we give them oxygen becker says. we jolt the heart with the paddles we pump in epinephrine to force it to beat so its taking up more oxygen. blood-starved heart muscle is suddenly flooded with oxygen precisely the situation that leads to cell death. instead becker says we should aim to reduce oxygen uptake slow metabolism and adjust the blood chemistry for gradual and safe reperfusion. researchers are still working out how best to do this. a study at four hospitals published last year by the university of california showed a remarkable rate of success in treating sudden cardiac arrest with an approach that involved among other things a cardioplegic blood infusion to keep the heart in a state of suspended animation. patients were put on a heart-lung bypass machine to maintain circulation to the brain until the heart could be safely restarted. the study involved just 34 patients but 80 percent of them were discharged from the hospital alive. in one study of traditional methods the figure was about 15 percent. becker also endorses hypothermia-lowering body temperature from 37 to 33 degrees celsius-which appears to slow the chemical reactions touched off by reperfusion. he has developed an injectable slurry of salt and ice to cool the blood quickly that he hopes to make part of the standard emergency-response kit. in an emergency department you work like mad for half an hour on someone whose heart stopped and finally someone says i dont think were going to get this guy back and then you just stop becker says. the body on the cart is dead but its trillions of cells are all still alive. becker wants to resolve that paradox in favor of life. interesting article but wheres the one about truck makers .