In a study from Denmark, victims of cardiac arrest who got cardiopulmonary resuscitation (CPR) from a bystander were more likely to eventually return to work.
Researchers studied 4,354 workers who had cardiac arrests outside of a hospital between 2001 and 2011. While just 796, or 18 per cent, were alive 30 days later, about three in four of the survivors were able to go back to work.
Chances of return to work were 38 per cent higher if a bystander performed CPR than if they didn't.
"That more than 75 per cent of all survivors were capable of returning to work is a remarkable result," lead study author Dr. Kristian Kragholm, of Aalborg University Hospital and Aarhus University in Denmark and a fellow at the Duke Clinical Research Institute in Durham, North Carolina.
"It is even more laudable that the survivors were able to earn the same salary as before their arrest."
Cardiac arrest involves the abrupt loss of heart function, breathing and consciousness. Unlike a heart attack, which happens when blood flow to a portion of the heart is blocked, cardiac arrest occurs when the heart's electrical system malfunctions, often due to irregular heart rhythms. Cardiac arrest may occur with no warning and is often fatal.
Chest compressions or CPR can help restore circulation, increasing the odds of survival.
Starting in 2006, Denmark began requiring certification in basic life support as a condition for receiving a driver's license.
Kragholm and colleagues analysed data from the Danish Cardiac Arrest Registry as well as government records that showed whether people were employed, and if so how soon they returned to work and how much money they earned.
People were more likely to return to work after the new license requirements took effect. They were also more likely to return to work if they were younger, more educated, and if a bystander or emergency medical professional performed CPR.
Chest compressions "take over the non-pumping heart's function and circulate the oxygen and blood to the brain," Kragholm noted in an email.
Among the 455 survivors who returned to work in the first six months of employment, individual and household incomes were comparable before and after the cardiac arrest.
One limitation of the study is that it can only show a link between bystander CPR and cardiac arrest survivors returning to work; it can't show that bystanders cause return to work, the researchers note in the American Heart Association journal Circulation.
While bystanders alone can't ensure survival, immediate help from somebody nearby is essential, said Dr. Gordon Tomaselli of Johns Hopkins University School of Medicine in Baltimore, who is a past president of the American Heart Association.
"The bystander is only the first step in a chain of survival that also requires a good emergency medical system," Tomaselli, who wasn't involved in the study, said by email.
"Good CPR is temporizing and limits organ damage (especially brain) and as long as definitive treatment can be provided quickly (within minutes) we would expect to see better outcomes," Tomaselli said.
To see the survival benefits from bystander aid, CPR training must be commonplace, said Tomaselli.
"It would not be effective if people are not trained," he said.