Researchers have found that, for many patients with cardiac arrest, CPR may benefit them even if they do not regain consciousness immediately. In fact, an extra 9 minutes can help improve people's survival rates.

An analysis, published in The Lancet, studied how long resuscitation was administered to patients suffering from cardiac arrest. Interestingly, they studied the time periods of CPR used in the non-survivors. They found that, for some hospitals, doctors and nurses gave CPR for an average of 16 minutes, while others gave CPR for an average of 25 minutes. In the hospitals that administered CPR for longer periods of time, patients were 12 percent more likely to live. The additional time also allowed medical staff to incorporate different resources in attempts to improve survival rates.

The study excluded patients who suffered from cardiac arrest in emergency rooms or during procedures.

Doctors are often hesitant to provide CPR for extended periods of time for fear of neurological damage. But the researchers from the University of Michigan say that, in cases with longer periods of CPR administration, patients are no more likely to suffer from neurological damage than their peers who recover immediately.

They found that extended CPR tends to have the best effect on patients who did not respond to the defibrillator, which gives them a shock in an effort to jump start the heart.

Cardiac arrest tends to occur in patients who are more sickly or elderly than people who suffer from cardiac arrest outside of hospitals. While in common parlance the terms "cardiac arrest" and "heart attack" are often used interchangeably, the terms are not synonyms. A cardiac arrest occurs when the heart stops, while a heart attack is brought on by a blockage.

Researchers could not give an optimal time for CPR administration, and concede that some patients may not benefit from longer CPR times. Indeed, longer times could mean that doctors spend too much time trying to save them, when the cause of their death is not cardiac arrest.