A new study published in The Lancet Public Health found that a series of public health interventions in Singapore cumulatively increased the likelihood of cardiopulmonary resuscitation (CPR) by bystanders during out-of-hospital cardiac arrests (OHCA) nearly eightfold and survival over threefold, underscoring the importance of such interventions to improve OHCA outcomes.

Sudden cardiac arrest is a serious healthcare concern all over the world. In the United States, over 350,000 cardiac arrests occur outside of a hospital annually, and about 90 percent of the victims die, according to 2015 statistics cited by the American Heart Association. In Singapore, a 2015 study found that about 70 percent of OHCA occurred at home and just over three percent of casualties survived to hospital discharge.

For a victim of sudden cardiac arrest in an out-of-hospital setting, CPR (performed by pushing hard and fast on the center of the chest) by a bystander could save their life. But in many communities around the world, the rate of bystander CPR is low, prompting some health authorities to initiate bystander-focused public health interventions at the community level to improve this.

The study by researchers at Duke-NUS Medical School (Singapore), Duke University (Durham, NC, USA), Singapore Health Services (SingHealth), the Singapore Civil Defence Force (SCDF) and the Singapore Ministry of Health’s Unit for Prehospital Emergency Care (UPEC) found that three national public health interventions in the city-state increased the rate of bystander CPR more than twofold. These measures included 1) dispatch-assisted CPR, 2) CPR and automated external defibrillator (AED) training, and 3) a first responder mobile application, known as myResponder, which alerts volunteer first responders trained in CPR to give life-saving assistance when they are in close proximity to someone experiencing cardiac arrest, before paramedics arrive on the scene.

In the nationally gathered datasets that were analyzed in this research, it was seen that, in general, bystander CPR was administered in nearly half (48 percent) of OHCA events. With the implementation of dispatch-assisted CPR, the likelihood of bystander CPR increased. Additional implementation of CPR and AED training further increased the likelihood of bystander CPR. Finally, the addition of the myResponder mobile application to the intervention strategies resulted in nearly eight times increased likelihood of bystander CPR compared to no intervention.

In this population, when all three measures were adopted, the likelihood of survival increased more than threefold, compared to no intervention. Variations were seen in the predicted bystander CPR probability and survival rate after adopting each of these measures for residential versus non-residential settings.

“Understanding the impact of public health interventions helps inform strategies to increase bystander CPR and targeted initiatives to improve survival from OHCA,” said Prof Marcus Ong, senior author of the study, who is Director of the Health Services and Systems Research Programme at Duke-NUS Medical School, and Senior Consultant at the Department of Emergency Medicine in Singapore General Hospital. “Importantly, our findings show that the increased likelihood of bystander CPR resulting from the bundled interventions was associated with increased survival.“

Prof Ong, who is also Director of SingHealth’s Health Services Research Centre, and Medical Director of UPEC and Senior Consultant at the Ministry of Health, Hospital Services Division, added, “Over the last 10 years, we have been advocating for the immediate application of chest compressions and the use of an AED during an OHCA. Patients stand a much better chance – up to 50 percent – of survival if those interventions are performed. Studies like this allow us to enhance our public health systems and save more lives in the process.”

SOURCE: Duke-NUS Medical School