Medihub - Medical Information - Emergency Medicine

New compressions-only recommendation for sudden heart attacks in adults.

Recent additions in the American Heart Association’s Cardiopulmonary Resuscitation (CPR) guidelines are made 2 years ahead of its scheduled review. The new recommendations emphasizes a shift from the traditional ventilation-compression (blow-press) method to the new compression-only guidelines comes amid revelations from 3 studies conducted last year which showed equivalent life-saving benefits with the hands-only CPR technique.

Past studies have increasingly revealed that increased compression to ventilation ratio will improve survival rates in both animal and human subjects. This led to the 30:2 compressions: ventilations recommendation of the last guidelines in 2005 which sought the need to increase bystanders’ quality and prevalence through the delivery of high-quality chest compressions.

The new hands-only guidelines should not come as a surprise for it is now known that effective compressions with minimal interruptions is key to improving patients’ outcomes. It is hoped that more bystanders will jump in readily to perform a life-saving act with the simplification of the CPR technique.

Cardiology Consultant at Alexandra Hospital, Dr Soon Chao Yang, explains to MediHub that continuous chest compressions produce a persistent cardiac output about 10-30% of the usual volume. It is thought that by stopping to deliver breathing will cause interruption of this constant perfusion to the vital organs (particularly the brain).

“Maintaining the momentum of blood flow is of vital importance. I believe the new chest compression only CPR makes sense.” Dr Soon said.

Improving bystanders’ response to delivering CPR

Despite convincing studies that bystander CPRs are able to double survival rates in cardiac arrests, few people are willing to do it. The apprehension is due to concerns about disease transmission, panic and fear of causing harm.

Experts hope that eliminating mouth-to-mouth contact during CPR will remove some of these issues and simplify the whole process into a more easily learnt and retainable skill that can be put to use quickly in an emergency.

Who is the hands-only CPR for?

This action should be taken only for adults who collapse suddenly, stop breathing and are unresponsive. The person is most likely to be having a cardiac arrest which happens after a heart attack or other heart problems.

Ventilations in such cases can be eliminated as the victim will still have ample air in the lungs and blood and continued CPR compressions keep blood flowing to the brain, heart and other organs.

Dr Soon highlights the importance of the compression in a sudden cardiac death situation. “The most important factor that determines the survival of the victim in a such a situation is the "down" time. It takes only 5-7 seconds for the brain to be deprived of blood, follow by loss of consciousness.

When blood flow is diminished for more than 5-10 minutes, brain damage that occurs as a result of oxygen deprivation is likely to be irreversible. Therefore, it is important that CPR is performed immediately to keep some blood flowing to the brain and other vital organs while more medical help is on the way.”

Children who collapse are more likely to have breathing problems and in such cases, mouth-to-mouth breathing should be used. That also applies to adults who are suffering from a lack of oxygen due to a near-drowning, drug overdose, or carbon monoxide poisoning. In these cases, people will definitely benefit from mouth-to-mouth ventilations to get air into their lungs and bloodstream.

How you can help

When an adult suddenly collapses, bystanders should activate the emergency service immediately ( the SCDF- 995- in Singapore) and provide high-quality chest compressions by pushing hard and fast in the centre of the chest (100 compressions per minute), without interruptions until medical personnel arrives to take over.

If you or a bystander was previously trained in CPR and is confident in the ability to provide rescue breaths with minimal interruptions in chest compressions, then conventional CPR can be executed with a 30:2 compression-to-ventilation ratio until help arrives.

However, if you or the bystander, though previously trained in CPR but without the confidence in providing conventional CPR with high-quality chest with rescue breaths, then hands-only CPR should be given.

“Most importantly, the public must know that CPR is only a temporary measure.” Dr Soon said. “The first thing they should do when witnessing a SCD is to call for help and ambulance before commencing CPR so that more definitive treatment can be delivered promptly.”

References:

1. Hands-Only (Compression-Only) Cardiopulmonary Resuscitation: A Call to Action for Bystander Response to Adults who experience Out-of-Hospital Sudden Cardiac Arrest. A Science Advisory for the Public from the American Heart Association Emergency Cardiovascular Care Committee. Michael R. Sayre et al. Circulation. Published online. DOI: 10.1161/CIRCULATIONAHA.107.189380