By Daniel Pendick
Harvard Health Blog
Cardiac arrest is the ultimate 911 emergency. The heart stops sending blood to the body and brain, either because it’s beating too fast and too erratically, or because it’s stopped beating altogether. Oxygen-starved brain cells start to die. Death occurs in minutes — unless a bystander takes matters into his or her hands and starts cardiopulmonary resuscitation (CPR).
Performing CPR keeps blood circulating until trained and better-equipped first responders arrive on the scene to jump-start the heart back into a normal rhythm.
“The brain is the most sensitive of the body’s organs to oxygen deprivation,” says Robert Graham, a health policy scholar at George Washington University and chair of a National Academy of Medicine (formerly the Institute of Medicine) committee that recently released a new report on ways to improve survival from cardiac arrest.
“If you can continue blood flow to the brain for those five, seven, or 10 minutes until the first responders get there, you’ve given that person the best chance that they have of recovery,” says Graham.
BETTER SURVIVAL RATES
In a July issue of the Journal of the American Medical Association (JAMA), two teams of researchers provided compelling proof of the principle that “time equals brain,” and that efforts to improve the response to cardiac arrest can pay off.
In the ideal scenario, if a bystander witnesses someone go into cardiac arrest, he/she should call 911, start CPR right away, and continue doing it until another bystander or first responder can use an automated external defibrillator (AED).
AEDs are portable gadgets that deliver a brief electrical shock to the heart to get it pumping normally. They’re increasingly found in public places, such as shopping malls. Unfortunately, they often sit unused in their cabinets, even when there’s a real emergency.
One team evaluated the impact of a North Carolina initiative to train the general public in CPR and AED use. As part of the campaign, emergency workers also received training in how to recognize cardiac arrest and respond appropriately.
This team’s study covered nearly 5,000 cardiac arrests that occurred between 2010 and 2013 in North Carolina. The percentage of people who received ideal cardiac arrest care increased from 14 percent to 23 percent during that period. At the same time, survival without brain damage increased from 7.1 percent to 9.7 percent.
The other team mined a database of 168,000 out-of-hospital cardiac arrests that occurred in Japan between 2005 and 2012. During that period, the percentage of people with cardiac arrest who received bystander CPR increased from 39 percent to 51 percent. At the same time, “neurologically intact” survival increased from 4.1 percent to 8.4 percent.
You can get lost in all these numbers, but the overall message is that having more people on the street who can recognize and respond quickly to a cardiac arrest saves brains — and lives.
There’s still plenty of room for improvement. Of the 400,000 or so Americans who go into cardiac arrest outside of a hospital every year, only 6 percent survive the crisis. That low percentage might have something to do with the fact that only 3 percent of Americans learn how to do CPR each year.
The National Academy of Medicine report showed that some communities have substantially boosted survival from cardiac arrest. Seattle, for example, has improved cardiac arrest response on two fronts — in the number of trained bystanders and in the effectiveness of first responders.
In fact, Seattle’s survival rate has exceeded 60 percent for out-of-hospital cardiac arrests that were witnessed by someone. Compare that to the single-digit rates in many other urban areas.
“It’s really been a reflection of individual leadership and having people who decide this is important and are willing to work on it for 20 years,” Graham says. “You have a larger cadre of individuals who are trained to recognize cardiac arrest and who have a mindset to respond.” Communities like Seattle “can serve as benchmarks to say this is possible. It’s not insurmountable,” Graham adds.
The National Academy of Medicine report offers recommendations for how to get there from here. Two key ones are creating a national cardiac arrest registry and expanding programs in schools and communities to train people in CPR and AED use.
IT’S IN YOUR HANDS
If you want to be ready to help someone who goes into cardiac arrest, the watchwords are “recognize” and “respond.”
Recognize: Many people don’t know the difference between cardiac arrest and a heart attack or fainting spell. A person in cardiac arrest doesn’t breathe, doesn’t have a pulse, and can’t respond to you. Someone having a heart attack usually is conscious and breathing, has a pulse, and can answer your questions.
Respond: Here’s what you should do if you witness someone go into cardiac arrest:
1. Call 911 right away, or have someone else do it. That call means emergency medical responders are headed your way.
2. Start hands-only chest compressions: Put one hand over the other, and place both on the person’s breastbone, in the middle of his or her chest. Press hard enough to make the chest move inward about an inch. Relax, and repeat. Do this about 100 times a minute. For the right tempo, think of the beat to the Bee Gees’ disco anthem “Stayin’ Alive.”
3. Keep doing CPR until someone arrives with an AED, either a bystander who’s obtained one from a nearby business or building, or a first responder.
Mouth-to-mouth breathing isn’t necessary if you’re doing CPR. That’s because the individual’s blood has enough stored oxygen to keep him or her going for a while.
Many organizations sponsor CPR and AED training programs. Two notable ones are the American Heart Association and the American Red Cross. Some are in-person courses; others are online. Many local health departments offer CPR training, including “friends and family” classes for people close to someone at risk of cardiac arrest.
The investment of time and effort to learn CPR is small. The potential payoff — saving a life — is huge.
(Daniel Pendick is Executive Editor of Harvard Men’s Health Watch.)