If you have a friend or loved one with coronary heart disease, you'll want to know what to do in the event of sudden, cardiac arrest. A study reported in the journal The Lancet compares the benefits of mouth-to-mouth ventilation and chest compressions versus chest compressions alone and their findings may surprise you.
A heart attack typically occurs when a blood clot in a coronary artery completely blocks blood flow to a segment of the heart. When this blockage takes place, portions of the heart muscle are deprived of oxygen and become permanently damaged. Damage to the heart muscle can impair the ability of the heart to pump blood efficiently, which can lead to heart failure. The impaired blood flow can also damage the electrical system of the heart and lead to arrhythmias.
A study reported in The Lancet (Volume 369, page 920) found that victims of cardiac arrest (heart attack) stand a better chance of surviving if a bystander performs only chest compressions and forgoes mouth-to-mouth ventilation.
Japanese researchers found that of 4,068 adults who had a cardiac arrest outside the hospital, those who received chest compressions alone were twice as likely to survive with good brain function 30 days later as those who received standard CPR (22% vs. 10%).
The findings go against the long-held principles of CPR, which combine chest compressions and "rescue breaths." But they also support what a number of experts have said for years: Mouth-to-mouth resuscitation does little for cardiac arrest victims and may actually dim their already low odds of survival.
What's more, mouth-to-mouth ventilation is often a barrier to bystanders initiating CPR. Chest compressions are vital to keep blood flowing to and from the heart until medical help arrives; stopping to deliver rescue breaths may impede this blood flow.
Bottom line: Though these study results have spurred calls for revamped CPR recommendations, guidelines from the American Heart Association (AHA) still advise rescue breaths (two breaths after every 30 chest compressions) for all cardiac arrest victims. We advise that you follow the AHA recommendations.
