New CPR guidelines: Simplicity to the rescue

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New CPR guidelines: Simplicity to the rescue

Rapid chest compressions keep blood flowing to the brain and other vital organs, so push hard and push often.

For decades, the American Heart Association and other groups have promoted cardiopulmonary resuscitation (CPR) as a way to save a life, even without a medical degree. Countless classes, books, and certifications are available. Hollywood has done its part, searing an unrealistic version of CPR into our imaginations with portrayals of heroic, lifesaving rescues.

The reality, though, is quite a bit different — and more complicated. For those stricken by sudden cardiac arrest outside the hospital, the survival rate is only about 5%, a figure that hasn't changed much over the years. CPR guidelines have been confusing, with the methods varying with the victim's age, the cause of the cardiac arrest, the number of rescuers present, and whether the rescuers have medical training.

Moreover, despite all the efforts to popularize CPR, it's much more difficult than it might seem. It's hard — and stressful — to perform correctly in a real-life emergency, especially if the victim is a loved one. Several studies have shown that CPR training "wears off" quickly. Even medical professionals often fail to push hard enough during chest compressions and take too long with the ventilations — those puffs into the lungs that are supposed to supply the blood with oxygen.

Automated external defibrillators (AEDs), the devices that shock the heart back into a normal rhythm, have added another layer of complication. Some experts predicted that the AED would make CPR obsolete. In fact, in some circumstances, survival statistics haven't improved after emergency medical professionals started using AEDs, perhaps because CPR was neglected. Studies published in 2004 and 2005 suggest that the two approaches complement each other, and even when using an AED, it's important to do CPR.

The simpler solution

The American Heart Association has been trying to simplify CPR, at least as far as the lay public is concerned. The guidelines published in 2000, for example, eliminated the advice that you should check the victim's pulse, because too many people were wasting valuable time feeling for a pulse instead of doing the real work of CPR.

In November 2005, the association issued new guidelines. Again, simplification was a major theme. They set a universal compression-ventilation ratio of 30:2 (more on this below), a single technique for opening the airway of an injured person, and a one-shock strategy for the AED, instead of "stacking" three shocks in a row.

The new recommendations emphasize the importance of chest compressions. To be effective, the compressions need to be hard and fast, and rescuers need to keep at them.

Here's an overview of the new guidelines. The complete guidelines are long, so we're just mentioning the highlights. And if you're an eyewitness to the cardiac arrest, the recommendations are slightly different.

1. Call the emergency number — usually 911.

In many places, an ambulance or the fire department should arrive in seven to eight minutes. When you call, the dispatcher will probably ask you some basic questions about what happened, the type of aid available, and, of course, your location. It's important to stay calm and answer the best you can. Don't hang up too soon! The dispatcher may coach you over the phone.

Step 1

The new guidelines say that at the same time you're calling for help, you should get the AED — if it's immediately available. That's a big if. And "immediately" is a matter of judgment. You shouldn't put off starting CPR too long while searching for an AED. The little bit of blood flow that CPR creates is especially important for brain tissue, which can start to die in minutes without some circulation. It makes the situation a lot easier if you're not the lone rescuer. While one person starts CPR, another person can call 911 while someone else fetches the AED.

2. Open the airway and check for breathing.

The purpose of opening the airway is to let the person breathe. Previous guidelines said that lay rescuers should open the airway of injured victims with a maneuver that involved hooking your fingers around the jaw and pulling it forward. The "jaw thrust," as it is called, was supposed to minimize movement and therefore the risk of further injury. But it's difficult to do. Besides, experts now think it may not be any safer than another standard maneuver for opening the airway, called the "head tilt-chin lift," which involves pushing down on the forehead and lifting the chin. The head tilt-chin lift is now the universal recommendation.

Step 2

The "check for breathing" guideline has caused some confusion. The new guidelines say check for normal breathing. After cardiac arrest, people often gasp for air. Those gasps, though, don't count as normal breathing. In fact, if the person is unresponsive and gasping for air, that's a sign that he or she has suffered a cardiac arrest.

3. Give two rescue breaths that last about a second each and make the chest rise.

Previous guidelines told rescuers to take a deep breath before delivering a rescue breath, but the new ones say normal breaths are all that's needed. Blowing up the chest can interfere with the effectiveness of the chest compressions. Besides, during CPR, the flow of blood to the lungs is reduced, so extra air isn't going to accomplish much. The manikins used to teach CPR encourage people to blow hard in order to make the chest rise. The new guidelines say the manikins should be changed so people don't need to blow so hard.

Step 3

Rescue breaths can be important, especially for children or if the person has been in cardiac arrest for several minutes and oxygen levels in the blood are running low. Yet during the first few minutes of cardiac arrest, chest compressions are probably much more important to the person's survival. In fact, some studies have shown good results with "compression only" CPR. So while the new guidelines do recommend rescue breaths, they also warn against taking too long to do them and delaying chest compressions.

4. Start chest compressions.

The old guidelines recommended a compression-to-ventilation ratio of 15:2; for children and infants, the recommended ratio was 5:1. Now everyone (except for infants) is supposed to get 30 compressions for every 2 breaths. The change is part of the effort to simplify the guidelines. It also reflects the recognition that chest compressions are the essential part of CPR, because the compressions keep the blood flowing to the vital organs.

Step 4

The guidelines say to "push fast and push hard" at a rate of 100 compressions per minute. Yet the rescuer must also allow time for the chest to recoil, so each successive compression pushes blood through the circulatory system. The heel of one hand should be in the center of the chest between the nipples, and the second hand should be on top of the first so you can put more power into each downward thrust. The chest should go down by 1½–2 inches.

This is hard, exhausting work, to say nothing of the stress involved in trying to save a life. If there are other people around who can help, it's a good idea to allow someone to take over after about two minutes.

5. If an AED is available, give the person a single jolt (each time you use it).

You shouldn't wait around for an AED to start CPR. On the other hand, if one is available, you should use it as quickly as possible. You don't have to do CPR first.

Step 5

Previous guidelines recommended three shocks in a row. Now most AEDs are designed so that if they are going to help at all, a single shock should be enough. It may take several minutes, though, before the heart starts beating effectively again in a way that's recognizable. So, new guidelines say that rescuers should perform CPR after using an AED. That way there's some blood flow before the heartbeat resumes. After about two minutes of CPR, the AED can be used again to assess the heart's rhythm and, if necessary, deliver a second shock.

Don't let the perfect be the enemy of the good

When started right away and correctly, CPR may double or even triple a person's chances of surviving cardiac arrest, although it's usually a small chance to begin with. AEDs, in the right circumstances, can make a big difference. University of Arizona researchers published a study in the New England Journal of Medicine of a program that involved AED training for security guards at casinos. The survival statistics were impressive: Of the cardiac arrest victims whose collapse was observed and who were defibrillated within three minutes of their collapse, 74% survived.

In contrast to this and other success stories are the gloomier overall statistics. We've mentioned the low 5% survival rate for out-of-hospital cardiac arrest. Only a third of people who suffer a witnessed cardiac arrest receive CPR during those first few crucial minutes after their collapse. Undoubtedly, and understandably, some people are too scared or shocked to attempt it. But there's wide consensus that less-than-ideal CPR, and especially chest compression, is better than no CPR.

Simplifying CPR may help people overcome their reluctance to attempt it. The heart association is moving in the right direction, but it could do more to take the mystery out of this lifesaving technique. The association has posted valuable information about CPR on its Web site that we depended on while preparing this article. But some of it is buried in long documents. And while CPR classes are fine, people shouldn't be made to feel that they need to have taken one to attempt CPR when faced with an emergency.

If you Google CPR, a Web site developed by Dr. Mickey Eisenberg at the University of Washington comes up first. Eisenberg has done a great job of boiling down basic CPR to a few steps with an animated graphic. The heart association should do the same.

Last updated:	September 05, 2008