CPR during cardiac arrest: someone’s life is in your hands

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Cardiac arrest is the ultimate 911 emergency. The heart stops sending blood to the body and brain, either because it is beating too fast and too erratically, or because it has 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).

Doing 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 massive new report on ways to improve survival from cardiac arrest. “If you can continue blood flow to the brain for those five, seven, or ten minutes until the first responders get there, you have given that person the best chance that they have toward recovery.”

New evidence backs better survival with CPR

In this week’s Journal of the American Medical Association (JAMA), two teams of researchers provide compelling proof of the principle that “time equals brain,” and that efforts to improve the response to cardiac arrests can pay off.

In the ideal scenario, a bystander

  • witnesses an individual go into cardiac arrest
  • calls 911
  • starts CPR right away, and continues doing it until another bystander or first responder can use an automated external defibrillator (AED) to shock the heart back to a normal rhythm.

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% to 23% during that time period. At the same time, survival without brain damage increased from 7.1% to 9.7%.

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% to 51%. At the same time, “neurologically intact” survival increased from 4.1% to 8.4%.

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.

More people need to learn CPR

There is 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% survive the crisis. That low percentage might have something to do with the fact that only 3% 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 the first responders. In fact, Seattle’s survival rate has exceeded 60% 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 has obtained one from a nearby business or building, or a first responder.

Mouth-to-mouth breathing isn’t necessary if you are doing CPR on someone you saw go into cardiac arrest. That’s because the individual’s blood has enough stored oxygen to keep him or her going for a while.

Get trained

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 departments of public health also provide 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.



Related Information: Harvard Heart Letter


  1. Nafiul Hasan Sufi

    The Cardio Pulmonary Resuscitation method is needed to be explained with it’s importance. If it is closely observed then we can see the survival rate evidence. In my personal experience as a medical person I have observed a brilliant success with CPR method. CPR brings an excellent stability. Such stability gives successful outcome, as a result survival rate increases significantly. Progress in increasing survival rate can be done easily through the CPR method.

  2. C.M. Rivers

    This is an excellent, and is very informative and timely.

    Fortunately, in our community, all Paramedic vehicles have defribrilators, but what and how we can do in the meantime is most valuable.

    C.M. Rivers


    Thank you very much for serving and information.

  4. mamo

    Can we find pulse in ventricular tachycardia

  5. mamo

    Is there pulse in ventricular tachycarfia

  6. Elliot Fisch

    This is a very good summary and discussion of this study and the problems around Sudden Cardiac Arrest survival.

    What is overlooked in all of this, and other studies, is that everyone states that someone should get an AED. However, you can’t get an AED if you don’t know where it is.

    AED Link is a web-based software system for 911 centers that provides them with the location of AEDs within the community. It can also automatically notify AED responders to bring their AED on-scene. It is currently installed in 30 EMS systems in 12 states and in Canada and the Cayman Islands. Responders are reporting their arrival to be somewhere between 3 and 5 minutes before EMS arrives.

    Elliot Fisch, President
    Atrus, Inc.

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