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"When I asked for a point of comparison, he said Detroit was 4%."

The stats on Detroit emergency responders are utterly embarrassing. You pretty much can't count on police, fire or EMT even if you had a gunshot wound in a burning house and the shooter was still there.

So I'm guessing the issue in Detroit is less about technique and more about no access to trained responders.

*And to be clear, I'm not blaming the emergency responders in Detroit for the problem. The city is huge and spread out so it takes a long time to get to the scene, there's no funding for additional outposts or training, and the jobs are dangerous making them unattractive to people with other options, and there's a higher than average amount of serious crime and emergencies.

At it's height Detroit was a city of ~2 million people. As of the 2004(?) census, the city fell below 1 million (~800k?) and lost a lot of Federal funding, spawning the constant budget crisis; furthering the downward spiral.

"Seattle has the highest survival rate for heart stop events in the world at 56%. That's because of pioneering advances in EMT training, broad availability of AEDs, high percentage of people trained, etc."

Statistic is true, but to say it is because of those things would requite some further analysis. Given confounding factors I don't think you can make that claim.

Seattle has an obesity rate of 22.5%, compared with 35.7% nationwide, and 33.1% in Detroit. Obesity is a major risk factor for cardiac arrest.

Seattle is also extremely white for a large American city, 67.1%, versus a place like Detroit which is 82.7% African American. Black American's have significantly higher incidences of hypertension and cardiac disease than White Americans, both for reasons that seem to have some unrealiable relations to genetic heritage but more significantly due to social stressors related to racism and overrepresentation of poverty.

Speaking of economics, Seattle has a median household income of $45k, while Detroit has a median household income of $26k. Cardiac Arrest risk factors are greatly exacerbated in the United States by poverty.

I don't deny the importance of instituting up-to-date protocols for Emergency health personnel, broad equipment supply, and widespread lay education. But to give them all the credit is to ignore Seattle's many advantages, and Detroit's many other sufferings.

> AEDs don't actually bring you back to consciousness. They just make CPR more effective. (much more!)

Perhaps a trained medical professional will correct me, but I've worked closely with the technology for years and I don't believe this is accurate. An AED can indeed bring someone back to consciousness if the shock is successful. If it isn't successful, then it wouldn't affect the efficacy of CPR one way or the other.

The rest of your comment seems spot on.

This is correct. The only point of defibrillation (automatic or not) is to stop ventricular tachycardia or ventricular fibrillation (electric rhythms that don't cause effective heart contractions), and kick-start a sinusal (normal) rhythm.

If the cardiac arrest is the result of another mechanism, defibrillation is ineffective.

If the cardiac arrest is the result of something else, does defibrillation hurt anything? Or does it have no effect either way?

AEDs are smart enough not to shock unless they detect VF. This is important because defibrillating a normally beating heart could actually cause VF. Would-be rescuers may not always be trained well enough to tell the difference between cardiac arrest and something else, such as a seizure or fainting.

But to your specific question: If a patient is in cardiac arrest but not in VF, then this means his heart has completely stopped. Forcing defibrillation won't likely improve the situation, but nor can it make it much worse.

Finished a 2-day first aid+CPR course today, the stat was that ~0.2% (or was it 0.02%) or people getting CPR have their heart start without a defib (AED or at the hospital) (also am a biomed engg researcher working on arteries but not the heart directly). CPR is bascially to keep the person somewhat oxygenated until they can get a defib (such as from an AED). A study found a 39% boost in likelyhood in surviving to being discharged from the hospital if AED+CPR was used compared to CPR alone [3]

An AED disrupts the fibrillation of the heart - often an outcome of a heart attack. Fibrillation is basically different parts of the heart firing randomly, with the effect that not much blood gets pumped. A defib (from AED or otherwise) is like a hard reboot of the heart, to try to reset the heart so it all contracts together again.

Consciousness is more to due with a neuro-state, which is affected by blood flow so its a symptom of the heart problem rather than the problem itself.

Also, as someone else mentioned, heart stopping /= death anymore, it is determined by brain activity [2]

[1] http://intensivecare.hsnet.nsw.gov.au/cardiac-arrest [2] http://en.wikipedia.org/wiki/Death#Diagnosis [3] http://depts.washington.edu/chru/May-20-A-Wicks-2_JC.pdf

Where are come from(Poland) you have to learn how to do CPR as a part of your driving test - in case of an accident you are required by law to stop and help, so it's only logical that CPR skills are required to get a driving licence. So most people know how to do it, they had to learn it to be able to drive.

Same in Germany and possibly more countries in Europe. And here in Germany there are also special courses for giving first aid to children available to parents at low to no cost.

I've had CPR training here in the US four times now, and I think two of those times were free (Boy Scouts, school, and, I think, Red Cross, but I had to pay for scuba rescue diver.) There will be some exceptions, but almost anyone who would claim that cost is the reason for not doing it is someone who wouldn't bother even if it were free.

> --Modern CPR (for adults) no longer includes rescue breaths.

That's only for bystanders for the reason you cite (reluctance to give aid). Rescue breaths are helpful and those of us who have to respond for our employer still give them. I carry around a barrier mask all the time now.

Source: I have the HCP level CPR cert.

This is a barrier mask, for those of us that didn’t have a clue: http://www.staples.com/Ambu-CPR-Barrier-Masks-with-Key-Chain...

That spiral in the middle is the one way valve.

Here's a link for those of us outside of the US: http://www.aeduniverse.com/ADSafe_CPR_Barrier_Mask_4053_p/40...

So I must know a US zip code to even be able to see that page? Never seen that before, quite obnoxious regardless if you live in the US or not.

Rescue breaths with CPR are also the standard for drowning victims, still. I believe it's still being taught as the standard for diving medicine, even volunteer/buddy rescues.

Not being in the medical industry, I'm curious what people say about the 4th paragraph here, indicating that many/most physicians would prefer not to have CPR performed on them. http://www.guardian.co.uk/society/2012/feb/08/how-doctors-ch...

Exactly one, a healthy man who'd had no heart troubles (for those who want specifics, he had a "tension pneumothorax"), walked out of the hospital.

I was recently witness to exactly this situation. The father of a friend of mine, an otherwise healthy man in his late 50s, collapsed when his heart stopped due to what was later diagnosed as some heart rhythm problem (I'm not sure exactly the cause). A friend of the family performed CPR until the ambulance arrived (which took a while, this being a rural location).

Less than a week later he was back on his feet.

I'm not a medical professional, so I can't say for sure that he would have survived without CPR; but I don't doubt it was key to his survival.

I was curious so I looked up the numbers on wikipedia: http://en.wikipedia.org/wiki/Cardiopulmonary_resuscitation#E...

The survival rates are:

CPR by a bystander: 4%

Cardiocerebral Resuscitation (i.e., chest compressions only without artificial respiration): 6%

No bystander CPR: 2%

So attempting CPR results on average in doubling the survival rate as opposed to just waiting for an ambulance, and chest compressions only are 50% better than chest compressions plus mouth-to-mouth.

I heard somewhere that plain old CPR was very unlikely to help. Still probably better than nothing if someone is there with their heart not beating. Does this go along with your stats?

EDIT: By sheer coincidence I found my stat about CPR while commenting on another thread. http://www.zocalopublicsquare.org/2011/11/30/how-doctors-die...

Plain old CPR by itself, with no ambulance on the way, is very unlikely to help. (That was another interesting tidbit - people almost never "wake up" while CPR is being administered).

Ambulance + plain old CPR, however, is much more effective than Ambulance + yelling "ITS GOING TO BE OK!" or playing Angry Birds or whatever. I don't remember the stats on effectiveness of performing CPR while waiting for the ambulance vs. not, but they were persuasive.

This also means that if you are in, say, a wilderness survival situation where help is not coming, CPR will not save a life, but it is still recommended that you perform it-- the emotional impact of just watching somebody die will be dangerous to the survivors.

A 2% chance of recovery is better than a 0.01% chance of recovery anyway.

My parents are GPs. They somewhat recently had an old man have a heartattack in their waiting room, and basically had to give him CPR + rescue breaths (via one of those squeeze bottle ventilators) for about 10 minutes before the ambulance arrived.

The hell of it was, it did work. The guy kept waking up from it while they were doing it, being very grumpy that people were pressing on his chest, and the moment they stopped he'd go unconscious again. Continued through the normal CPR and the ambulance's CPR apparently.

Unfortunately in the end he didn't make it (heart just would not restart fully).

When I took a CPR class a few years back, we were told that the point of "Samaritan CPR" was really just to keep the person going until a first responder got there, but that the chances of survival past 5 or 10 minutes got increasingly low without actual medical attention.

I've been in a situation where we were administering CPR to someone who simply could not have been helped by CPR (although there was no way of us knowing that at the time). We were relieved by first responders in about 3 minutes from calling 911 though.

Plus, as others have said, it's also beneficial for the bystanders to be doing something beneficial. In my own situation, I didn't know for sure that CPR wouldn't have helped until the autopsy came back. That's a pretty big time frame to sit around and wonder if you could have done anything or not. If you're just a random person on the street, you may never get that information to ease your mind.

"--Modern CPR (for adults) no longer includes rescue breaths. Mouth-to-mouth was too much of a turnoff, and chest compressions alone are very effective given the response times of ambulances."

I heard this years ago, and both times that I took CPR certification classes since then, we did mouth-to-mouth anyway. I guess different courses are different.

My wife (an MA for a pediatrician) told me the current standard she needs to test to is 25 compressions per rescue breath.

I took part in this:

https://www.cprundead.ca/guinness-event

and they specifically said that mouth-to-mouth is no longer a part of it. It's all about the chest compressions.

It depends on who teaches it. I believe the American Heart Association got rid of rescue breaths but the American Red Cross still trains for two breaths every 30 compressions.

Are they teaching the "100 chest pumps per minute" technique now?

I recall seeing that it is almost as effective as the "legacy" CPR rescue breaths.

It's honestly super easy to remember, and I'll feel comfortable performing it if I find myself in that situation.

I've read that a good mnemonic is going roughly by the beat of "Stayin' Alive".

Finished a two-evening first aid course with St Johns on Tuesday here in Australia. The CPR instruction for infants, children and adults alike all included a pattern of 30 compressions then two mouth-to-mouth breaths.

The child/adult numbers were coalesced to reduce confusion. You can also get away with no rescue breaths, not just because of the ick-factor others have mentioned, but because your compression of the chest is also compressing the lungs, providing enough airflow for the needs - and just as importantly, you haven't stopped compressing to deliver the breaths. Similarly, if you don't need to move to deliver the breaths, you don't need to find your correct compression spot on the chest again.

CPR's are not very effective. A large number of doctors do not want CPRs to be done on them. http://www.radiolab.org/blogs/radiolab-blog/2013/jan/15/bitt...

If you go read the abstract of the study cited, you should note that the mean age of the physicians interviewed was 68. I think hospitals do a lot of unnecessary CPR if the wishes of the patient are not known. If someone expires after a long illness or after a very difficult surgery there is little and less chance that perfunctory CPR will be helpful. There is a lot of difference for a relatively fit person who collapses on a treadmill. The odds are stacked against them but its not nearly so futile.

The study asked about "preferences of physician-participants for treatment given a scenario of irreversible brain injury without terminal illness", which is a very different scenario than randomly having a heart attack when you're 50 and otherwise in okay health.

Random heart attacks in people who are otherwise in ok health are not common.

http://www.cdc.gov/heartdisease/facts.htm