USC–led study shows that bystander CPR is associated with favorable neurological survival for drowning victims in cardiac arrest.
Two choices: Wait for emergency responders to arrive or start administering CPR yourself.

That decision could be the difference between a good neurological recovery or a coma, brain death or even death for a drowning victim in cardiac arrest, according to a study led by Joshua Tobin, associate professor of clinical anesthesiology at the Keck School of Medicine of USC, to be published in the June issue of Resuscitation.

“What we found is that when bystanders begin CPR before emergency personnel arrive, the person has a higher chance of leaving the hospital and leading a life reasonably close to the one they had before the drowning,” Tobin said.

Tobin, of the American Red Cross Scientific Advisory Council, collaborated on the study with other members. Using a database, the team identified more than 900 children and adults who had experienced cardiac arrest after drowning. The researchers then set out to determine what factors influenced positive and negative outcomes for these patients.

“When we talk about cardiac arrest, there’s no doubt that we want people to survive. But surviving and being in a persistent vegetative state would not be considered a success by most people. That’s why we chose to stratify the results by favorable or unfavorable neurological outcomes,” Tobin said.

A favorable neurological outcome was defined as good cerebral performance or moderate cerebral disability at hospital discharge — an unfavorable neurological outcome was defined as coma or vegetative state, brain death or death.

The results showed that bystander CPR had a clear effect: Drowning victims in cardiac arrest were three times more likely to have a favorable neurological outcome if bystanders initiated CPR.

The study also found that application of an automated external defibrillator (AED) prior to the arrival of emergency services was associated with a worse neurological outcome. Tobin cautioned, however, that this finding needs additonal investigation.

“It’s difficult to say why AED application prior to EMS arrival portended a worse neurological outcome in this study. Perhaps AED application distracted bystanders from giving good, uninterrupted CPR,” Tobin said. “What we do know, though, is that this study adds to a growing body of evidence that bystander CPR improves outcomes in cardiac arrest. It also provides a compelling reason for people to learn this life–saving technique.”