Jury Still Out on Best Delivery of CPR

TUESDAY, June 13 (HealthDay News) -- Two new U.S. studies give no clear answer as to whether man or machine does a better job at providing lifesaving cardiopulmonary resuscitation (CPR).

One study found that traditional, manual chest compression worked better, while the other supported the use of an automatic mechanical device.

The first study was conducted by researchers at the University of Washington, Seattle. They compared survival rates of out-of-hospital cardiac arrest patients who underwent manual chest compressions to those who received mechanical compressions. The automated compressions are performed by a load-distributing band (LDB) that wraps around the patient's chest and attaches to a backboard. The electronic device restricts automatically to resuscitate the heart during cardiac arrest.

Nearly 1,100 people who suffered heart attacks outside a hospital were studied across the United States and Canada. Measurements included patient survival to four hours after the initial emergency call.

Researchers found very little difference in survival rates between patients treated with CPR and those who received the automated compressions -- 29.5 percent compared to 28.5 percent.

Furthermore, "as implemented in this study, the use of an automated LDB-CPR device for resuscitation from out-of-hospital cardiac arrest appeared to result in lower survival and worse neurological outcomes than traditional manual CPR," the researchers concluded.

In the second study, conducted at Virginia Commonwealth University in Richmond, Va., researchers examined patients cared for by an EMS system that had switched from using manual chest compressions during cardiac arrest to the LDB compressions. A total of 783 patients experiencing out-of-hospital cardiac arrest were evaluated.

The Virginia team found significant improvements in survival rates within the first four hours for patients treated with the LDB compressions. Survival rates also improved up to the time of hospital discharge -- rising to 9.7 percent in patients who received LDB treatment, compared to 2.9 percent in those who were given manual compression.

Findings from both studies are published in the June 14 issue of the Journal of the American Medical Association.

"Our results suggest that a resuscitation strategy using the LDB CPR on rapidly responding EMS ambulances is associated with improved outcomes, including survival to hospital discharge, in adults with out-of-hospital cardiac arrest. However, further research [a large, adequately powered, prospective randomized clinical trial that blinds the rescuers to the intervention until they decide to initiate resuscitation] is needed to further define the value of LDB in resuscitation," the Richmond group said in a prepared statement.