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Treating the Dead
Posted by
kdawson
on Tue May 01, 2007 09:05 PM
from the pining-for-the-fjords dept.
from the pining-for-the-fjords dept.
FlyByPC writes "According to a NewsWeek article, oxygen deprivation doesn't kill patients as much as the resumption of oxygen does. This discovery could bring about new ways of resuscitating people whose hearts have stopped."
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In other news... (Score:5, Funny)
Falling does not kill you (Score:5, Funny)
Parent
Re:Falling does not kill you (Score:5, Funny)
Hot cha cha cha cha!
Parent
Re:In other news... (Score:4, Funny)
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Re: (Score:3, Funny)
So, a slow Rip Van Winkle type recovery process instead?
God forbid, and hypothetically speaking, a heart attack victim from an ambulance ride to finally waking in a hospital recovery room days later could go from this [wikimedia.org] to this [wikimedia.org]?
I'm continually amazed at (Score:3, Insightful)
Re:I'm continually amazed at (Score:5, Interesting)
Parent
Re:I'm continually amazed at (Score:5, Funny)
I'm certain they would be fairly pissed-off.
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Re:I'm continually amazed at (Score:5, Funny)
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Re:I'm continually amazed at (Score:4, Interesting)
Unfortunately, my girlfriend doesn't share my enthusiasm for frozen fungus, so our freezer has more room devoted to more mundane things, like frozen vegetables and animals.
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Re: (Score:3, Interesting)
Re:I'm continually amazed at (Score:5, Funny)
Don't hold your breath...
And if you do, don't stop.
Parent
Re: (Score:3, Insightful)
Re: (Score:3, Interesting)
That is perfectly true, in theory. In practice, Britain's medical system certainly performs a lot of experimental medicine - usually "unofficially" (patient consents, but there's no paperwork), most frequently for conditions deemed highly life-threatening or otherwise terminal, but sometimes for less-serious but "untreatable" conditions. These are usually not "controlled" experiments, participation is usually large and pre-existing evid
Not completely new (Score:3, Informative)
Still some pretty nice work and may lead to quite a few lives being saved.
Re:Not completely new (Score:5, Funny)
"I recall reading an article in Science News late 70's or early 80's about some research showing it was the blood vessels in the brain spasming that lead to brain death."
Parent
Makes a little bit of sense. . . (Score:5, Interesting)
Re: (Score:3, Insightful)
bcccbcccbcccbcccbcccbcccbcccbcccbccc...
bccccccccccbccccccccccbccccccccccb...
Re:Makes a little bit of sense. . . (Score:4, Interesting)
A few years ago I recall hearing something about people drowning in very cold water and care having to be taken to restore oxygen slowly (Australian ABC Radio Heath Report - Dr Norman Swan), but I don't know what the primary source for that information was.
Parent
Make it simpler.... (Score:4, Informative)
I forget the actual numbers, but the idea was really to simplify the procedure [americanheart.org]. It's more important to get blood flowing through the heart than do the breaths, so this way inexperienced people spend less time fumbling around with the breaths and more time pumping.
Parent
Re:Make it simpler.... (Score:4, Funny)
There you go.
Parent
Re: (Score:3, Funny)
Re: (Score:3, Informative)
It came from research that shows that compressions are what get oxygen to the blood and the breathing was merely interrupting the far more important compressions.
The goal there is still to get oxygen to cells more rapidly.
Stew
Re:Makes a little bit of sense. . . (Score:5, Informative)
Parent
Re: (Score:3, Interesting)
And in case you've never had to do it, one round of CPR at an actual pace will exhaust you if you do it right. The new methodology
Re:Makes a little bit of sense. . . (Score:5, Informative)
First off, a public service announcement. The current guidelines (which are actually backed up by some pretty good science) are a ratio of 30:2 compressions to breaths. Another important thing to note is that the rate of compressions is 100/min. This is faster than you think and believe it or not is incredibly difficult to do. For the tempo, think "Another One Bites the Dust" (and pardon my irony).
Ok, now on to the reasoning behind the change. ("Well, I could explain it better, but I'd need charts, and graphs, and an easel.") Essentially, the flow of blood through the arteries and into the myocardium requires the creation and maintenance of a pressure head. Research has shown that it takes about 5-7 compressions to create that pressure head, and every time you stop pumping, you lose that pressure. Now only when this pressure head exists is oxygen being delivered to the myocardium, thus any time you stop pumping, you're creating a period of time in which oxygen is not being delivered. And apparently 30:2 was the best ratio for oxygenating blood in the lungs and delivering blood to the heart.
Here's the official guidelines and all the studies behind them in all their linky goodness. http://circ.ahajournals.org/content/vol112/24_supp l/ [ahajournals.org]
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Re:Makes a little bit of sense. . . (Score:4, Insightful)
There is not a single 'ideal' compression to ventilation ratio. We know that for garden variety cardiac arrest due to V-Fib, ventilation in the first minute or so is probably almost meaningless. We also know that for hypoxic arrests (like a drowning) that ventilation is far more important. We also know that VFib makes up a greater percent of adult arrests and hypoxic arrests are more common in kids (all of whom get the same ratio.) Moreover the AHA made this decision knowing that they didn't even know the ideal ratio for the single most common type of arrest in the community (from VFib.) The 30:2 ratio was a way of keeping it simple that is not perfect for every kind of arrest, but is a reasonable compromise to try to deliver at least a reasonably acceptable type of CPR to all victims of arrest.
That is a good thing for lay-rescuers, but the AHA understands that people who are more highly trained and knowledgeable will guide their actions based on that knowledge. For example, if my partner grabbed his chest and collapsed, I would run to the phone, call 911. Return to him, check for a pulse, and if he had none, start wailing on his chest like a crazed weasel on crack. I would not even consider breaking compressions to give a breath till at least minutes had passed - or more trained people arrived and ACLS could be initiated. If however, I pulled him out of a pool, I would check for breathing and if none, give two full rescue breaths. Then check for a pulse, if none, start CPR with probably about a 15-20:2 ratio. I would stop for a moment at 1 minute. If he had a pulse, I would continue breathing for him a full minute or two before I ran to the phone. If he had no pulse, I would give two last breaths and run for the phone.
Those are drastically different methods that I chose knowing that they would give him the best chance in either situation. But if you try to teach lay-rescuers that, you will get blank stares and some shitty-assed CPR. So it is better to make things as simple as possible and make them so at least everyone gets 'reasonable' CPR.
Nick
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This is a tech site, we use SI! That would be 1.7 Hz.
I counted, it fits nicely!
Verse
*breath* *breath*
Chorus
*breath* *breath*
Verse
*breath* *breath*
Chorus
*breath* *breath*
Wohoo, it's a good grove! I could go on all day. What? Oh, you're fine now? And it hurts? OK, I understand...
Re: (Score:3, Informative)
Ah, yes. That was one of the other changes to simplify resuscitation - don't bother checking for a heartbeat, start resuscitating right away. If the patient doesn't need it, he'll protest soon enough.
Difficult to do... (Score:3, Funny)
Must not be that hard for musicians then, especially us drummers. 240 BPM chest compressions, no problem!! Lemme just put both of my feet on 'em, I'll play 'em like a kick drum with dual pedals!
What about the brain though. (Score:4, Insightful)
It might be useful so organs could be used for a transplant.
Re:What about the brain though. (Score:5, Funny)
"It does not do any good to have a working body if I am still brain dead at the end of the process."
Why not? George Bush choked to death on a pretzel a few years ago, and nobody's noticed the difference ...
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Re: (Score:3, Funny)
This makes sense in a lot of ways. (Score:5, Interesting)
It even makes sense to me why sudden resumption of oxygen should be lethal. Oxygen is extremely toxic and aerobic organism, such as ourselves, had to evolve complex cellular machinery in order to utilize it for metabolic efficiency, while keeping the oxygen from damaging cellular structures, especially DNA. The sudden surge in oxygenated blood would probably overload this system. Apoptosis in this case may be a protective step by killing the cell before its DNA becomes damaged and possibly cancerous. Thus, flooding the heart with oxygen causes the whole heart to "take one for the team," and shut down completely.
The discovery that the cells are still alive, and can be revived with special treatment is extremely encouraging for the development of better techniques.
Old news -- reprofusion injury (really old news) (Score:5, Insightful)
I wrote about that >20 years ago, when I was writing for a biotechnology newsletter. After >20 years of research, they understand it much better today.
Every surgeon knows about reprofusion injury. You can go to Barnes & Noble and look it up in a surgery textbook.
I don't understand why Newsweek says it's new or that it wasn't known in 1993. I assume those doctors came up with some new detail in its treatment.
whoa (Score:5, Funny)
with the panel that reads "RESURRECT FOR FREE"?
Doesn't work on the dead (Score:3, Funny)
It's true (Score:3, Funny)
Or my favourite:
Q: "Did you hear?? Johnny fell 20 stories and LIVED!"
A: "Really? That's amazing!"
Q: "Yeah, unfortunately it was off a 21 story building..."
reperfusion injury isn't news (Score:3, Interesting)
She also explained that when the cells stop getting oxygen, they start going into anaerobic respiration, and the other issue is all the toxins that get released into the circulatory system once the heart starts pumping again.
Anyway, yeah - when a body dies, almost all the cells in the body are certainly still alive. That's not the point though - the cells have to be happy, then the tissues, then the organs, then the body as a whole. Once the body stops working as a whole, it doesn't matter that almost all the cellular components are, on a cellular level, still alive.
Says she, resuscitations in animals are even far less frequent than the 15% listed in the article for humans. And in the ones that do survive, they almost always have "reperfusion injury."
It's the brain we worry about, not the heart (Score:3, Insightful)
It's the brain that's exquisitely sensitive to oxygen deprivation. That 5-minute window refers to irreversible brain damage that begins to occur after ischemia, not heart damage. It's also well known that brain tissue releases toxic metabolites after oxygen deprivation doing damage above and beyond what the lack of oxygen itself did. There are a number of therapies aimed at reversing or blocking this phenomenon, but none have been successful yet.
The intervention that has been shown to be most effective in changing survival outcome once someone's heart has stopped beating is good quality CPR as soon as possible. Most of these other innovations like cooling have only a minimal effect changing a dismal outcome to a not-quite-as-dismal-but-still-pretty-dismal outcome. Most of these intra and post resuscitative interventions only succeed in allowing a patient to linger in the ICU for a few extra days before finally dying.
Night of the living patients... (Score:3, Funny)
radical emergency treatment (Score:3, Interesting)
Potentially, the greatest benefit of this research could be in cases where a patent comes in to the ER with the heart still beating, but too seriously injured to save with current knowledge.
At that point, doctors could potentially pre-treat the patient to inhibit the damage from reperfusion, get the heart-lung machine in place and essentially manage the process of cardiac arrest. They then have considerably more time to repair the damage surgically and treat blood chemistry problems. Once ready, they could then manage the reperfusion process carefully.
Eventually, another leap in survivability could come about once equipment becomes available to allow paramedics to handle managed arrest in the field.
Still later, as the technique is refined further it will no longer be such a last resort technique. It may open the door to surgical procedures that are simply out of the question today.
Assuming any of this works out, there will be a LOT of legal and ethical fallout. While the new techniques will likely result in saving a lot of lives where the patient goes on to substantially recover, it may also result in a number of cases where the patient lives but doesn't really recover. The latter happens now as well, but thus far society mostly just pretends it doesn't happen and ignores those stuck with the consequences (except when congress calls an emergency session attempting to make sure someone remains stuck with the consequences). It's infrequent enough now that we (as a society) more or less get away with ignoring it.
Ultimately it may force us to think legally and ethically about the difference between "not dead" and "alive" (and perhaps better terminology for the difference).
Re:Traditional Chinese Medicine Recognizes This (Score:4, Interesting)
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Re:FP!!!! (Score:5, Funny)
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Re:This was discovered in the US? (Score:5, Interesting)
Other arguments against socialized medicine include: years-long queues for certain sorts of procedures (which aren't strictly Necessary, but may be Incredibly Useful), the sheer cost of paying for it, and a tricky sort of little moral hazard problem with implications against freedom. (Specifically, if the government has to pay for your health care, then a - you're probably less likely to try and take preventative measures to maintain your health since the Government will deal with it and you won't have to pay for it as heavily as you would otherwise; this contributes to a larger problem: b- being unhealthy means more money out of the federal budget, so the government has a big incentive to make unhealthy activity illegals, and the next thing you know, they could be forcing tofu cubes down your throat screaming "it's good for you!!!!!" when all you want is a hamburger, a simple hamburger, for the love of all that is holy - well, figuratively speaking, anyway; you get the idea.)
The unarguable fact that's in support of socialized medicine is "it will make certain peoples' lives better". It will also probably make people's lives worse - rich people, healthy people who pay taxes, and Future people. For typical middle-class people, it's less than clear.
Parent
Some facts to back up your opinion please? (Score:3, Insightful)
In that case, I urge you too look at any country in Europe that has this socialized healthcare you detest so much. Europeans are much more healthy and spend an order of m
Re: (Score:3, Insightful)
Re:This was discovered in the US? (Score:5, Insightful)
Yes, actually, they are good American names.
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Thank Christ. I'd be worried if an MD couldn't spell "cells".