In a break from decades-old first aid guidelines, the American Heart Association on Monday endorsed "hands only" cardio-pulmonary resuscitation rapid chest compression without mouth-to-mouth resuscitation to improve the odds for victims of cardiac arrest.
The new guidelines, published in the journal Circulation, recognize that recent research has shown no real advantage to conventional mouth-to-mouth CPR in outside-the-hospital cardiac arrest cases. In addition, studies show that bystanders are often reluctant to perform mouth-to-mouth resuscitation on strangers, but are more likely to try rapid chest compression.
"We think that if we can double the number of bystanders who attempt CPR, we can save tens of thousands of lives every year," said Mary Fran Hazinski, a nurse at Vanderbilt University Medical Center and spokeswoman for the American Heart Association.
Sudden cardiac arrest is a leading cause of death in the United States. Every day, it claims 900 American lives. Only about 6 percent of victims whose hearts stop outside of a hospital survive.
Studies show that either mouth-to-mouth or hands-only CPR may double the survival rate from cardiac arrest, but bystanders typically step in to provide the potentially life-saving intervention in only about one-third of cases. That hesitation is rooted not only in reluctance to lock lips with a stranger, but by anxiety over how to perform conventional CPR, in which the rescuer breathes into the victim twice after every 30 chest compressions.
"Many times people nearby don't help because they're afraid that they will hurt the victim and aren't real confident in what they're doing," said Michael Sayre, chairman of the Heart Association committee that rewrote the guidelines.
In fact, effective chest compression can break the victim's ribs about one-third of the time. That's a risk well worth taking when the odds of survival without CPR are so slim.
The Heart Association also stressed that three-quarters of sudden cardiac arrest cases outside the hospital occur in the home. The bystander who needs to provide those chest compressions is often a loved one of the victim.
Conventional CPR that combines both chest compression and mouth-to-mouth resuscitation has been taught in first aid classes since the 1960s. That method has been under review since 1997. Two years ago, after considering multiple studies, the Heart Association recommended hands-only CPR only in cases where people were unwilling or unable to provide the rescue breaths as well.
The latest revision stems from three major studies published last year that showed no advantage in using mouth-to-mouth resuscitation in cardiac cases.
Dr. Chris Barton, acting chief of the Emergency Department at San Francisco General Hospital, supports the new guidelines. He said the latest research on CPR supports the notion that in the critical minutes before an ambulance or defibrillation device arrives, it is very important to provide uninterrupted, deep chest compressions.
"You want the chest to go down about 2 inches. I weigh 160 pounds, and when I do this I put about half my weight into it," he said. The pressure should be applied to the center of the chest, between the two nipples of the victim.
The compressions also have to come in rapid succession about 100 per minute. According to Hazinski, one easy way to remember the rhythm is that it is roughly equivalent to the beat of the 1977 Bee Gees' disco hit "Stayin' Alive."
"If you are untrained, just remember to push hard and push fast," Hazinski said. "Doing something is better than doing nothing."
These new guidelines are aimed at untrained bystanders, or to those who have been trained in CPR but are unsure they can perform it adequately. The message is, if there is any doubt, provide "hands only" CPR.
Although survival rates for cardiac arrest hover around 10 percent with CPR, Hazinski noted that rates have been pushed as high as 30 percent in cities, such as Seattle, that combine high bystander participation with a strong system of professional emergency medical response.
At best, CPR is a desperate measure. Survival rates are highly dependent on prompt arrival of a defibrillator the kind carried by ambulance crews and increasingly available in public venues such as airports and sports stadiums.
"If you have access to an AED Automated External Defibrillator, you want to apply that as early as possible," advised San Francisco General's Barton. "Early defibrillation is the most successful intervention you can do."
Heart Association guidelines
Q: Why is the Heart Association changing its guidelines?
A: Studies show that bystanders are reluctant to attempt conventional CPR, which involves chest compression and mouth-to-mouth resuscitation. New research shows that chest compression alone works just as well as traditional CPR. The thinking is, more people will try CPR if they don't need to include mouth-to-mouth breathing.
Q: Does this apply to all cases?
A: No. The new guidelines apply only to adult victims shortly after they collapse and have no pulse. They do not apply to children or drowning victims.
Q: Why not drowning victims?
A: Chest compression alone works only if there is oxygenated blood left in the body, but drowning victims have already consumed most of the oxygen in their bloodstreams. They need the air provided by mouth-to-mouth resuscitation.
Q: Why not children?
A: Cardiac arrest in children is rare. Most children whose hearts have stopped are suffering from respiratory arrest, from choking or conditions such as asthma. Like a drowning victim, they don't have oxygen in their bloodstreams.
For more on hands-only CPR: links.sfgate.com/ZCWJ