Science

CPR better with only chest compressions: study

Bystanders who need to perform CPR on someone suffering from cardiac arrest are likely more effective if they just deliver chest compressions, says a new study.

Bystanders who need to perform CPR on someone suffering from cardiac arrest in a home or public place are likely more effective if they just deliver chest compressions, without breaths, according to a new study.

The research, published Tuesday in the Journal of the American Medical Association, confirms earlier findings that "hands-only" cardiopulmonary resuscitation has better outcomes among rescuers with no first aid training.

The study was conducted by a team of Arizona physicians who launched a statewide program encouraging the use of compression-only CPR in 2005 to combat "dismal" cardiac arrest patient outcomes.

The procedure, favoured for its ease to learn and execute, relies on the rescuer to press down repeatedly on the patient's chest, acting as a blood-pumping replacement for their seized heart. In Arizona it was associated with an increase in the number of rescue attempts and a higher survival rate among cardiac arrest patients.

Of 4,415 Arizona patients observed in the study, all over 18 years old, 849 received hands-only CPR. Another 666 received conventional CPR, in which the rescuer alternates between chest compressions and mouth-to-mouth breathing to deliver oxygen to the patient's lungs. A further 2,900 patients were given no CPR at all. All CPR studied was delivered by people with no formal medical training.

The researchers found that 13.3 per cent of the compression-only patients survived and were discharged from hospital, compared with 7.8 per cent of those who received full CPR with both compressions and breaths.

Those who received no treatment had the worst outcomes, with only a 5.2 per cent survival rate.

The overall rate of rescue attempts also rose, from 28.2 per cent of cardiac arrests in 2005 to 39.9 per cent in 2009. That likely contributed to the survival rate climbing from just 3.7 per cent to 9.8 per cent over the same time period for patients in the study.

The study was not a randomized-controlled trial, something the physicians say would be impossible to do in this case as the decision to perform conventional CPR, compression-only CPR, or no CPR was at the discretion of the bystanders.

Canadian Heart and Stroke Foundation statistics show there are up to 45,000 cardiac arrests per year in Canada. Of that number, the organization says, 85 per cent happen in homes or public place, and less than five per cent of those patients will survive.

Study may help boost CPR rates

Calling out-of-hospital cardiac arrest a major public health problem, the Arizona doctors partnered with emergency medical personnel to launch a public education campaign about the benefits of compression-only CPR.

The program directly trained an estimated 30,000 people, and its message reached at least 500,000 in Arizona, the doctors said in the study.

The American Heart Association has also picked up the message, and has been running a hands-only CPR campaign across the U.S. since 2008, a program the Arizona doctors said likely helped their outcomes.

Still, they said the fact that fewer than half of bystanders attempt CPR on a cardiac arrest patient is problematic.

Although bystander CPR is associated with increased survival, the rate of performing this intervention remains unacceptably low, the authors write in the study.

CPR experts say would-be rescuers fear causing harm, worry about contracting a disease from mouth-to-mouth rescue breathing, panic and are scared by the complexity of the procedure.