Test devised to find when CPR is a lost cause

Published 9:00 pm Wednesday, August 2, 2006

NEW YORK – If your heart suddenly stopped, how long should rescue workers try to save you? Should you be taken to the hospital even if you can’t be revived and are likely to die?

Canadian researchers say they’ve devised a test that helps rescue workers spot those futile cases and save a frantic trip to the hospital.

Some paramedics with advanced training – those who can give drugs and start IVs – already are allowed to stop giving CPR if their efforts fail and they have consulted a doctor, said lead researcher, Dr. Laurie Morrison of the University of Toronto.

But 60 percent of Americans and Canadians, mostly in rural areas, are served by rescue workers who only have basic skills and don’t have that option, she said.

Taking such lost causes to the hospital ties up ambulances and emergency departments and the race to get there is hazardous for rescue workers and other motorists, researchers said.

Morrison said her group studied the issue after she was approached by frustrated paramedics. The researchers reviewed old cases, devised a three-point rule, then tested it in Ontario. Their findings are in today’s New England Journal of Medicine.

Few people survive a cardiac arrest, which is caused by an abnormal heart rhythm and brought on by a heart attack or heart disease, electrocution, drowning or choking. The victim loses consciousness and stops breathing. More than 300,000 Americans die of cardiac arrest each year.

In the Canadian experiment, only 41 of 1,240 patients, or 3 percent, survived. All were given cardiopulmonary resuscitation at the scene, hooked up to a defibrillator to try to shock their hearts back into normal rhythm and taken to the hospital.

Later, the rescue workers filled out a form, applying the three-criteria test to each case to see if it would have signaled that CPR be stopped. Termination was advised if a pulse couldn’t be restored, if the defibrillator determined that an electric shock shouldn’t be given, and if the cardiac arrest wasn’t witnessed by a rescue worker.

The researchers said the test closely predicted who was likely to die. Overall, 776 patients met the three criteria, and all except four died, a survival rate of 0.5 percent.

If the test were applied, it would reduce by about two-thirds the number of patients taken to the hospital, the researchers said.