Why we don't check for pulse before CPR

Medical procedures and first aid procedures are not all the same. What is appropriate in a hospital setting with medical professionals, who have access to medical equipment and medications, may not be appropriate for an untrained person in their home or in a public place.

Some medical providers may develop their own protocols which reflect their own areas of expertise and available resources and use mnemonics to help them.

The International Liaison Committee on Resuscitation (ILCOR) was formed in 1992 so that international resuscitation organisations could collaborate on resuscitation science and develop guidelines for CPR and Emergency Cardiovascular Care. It does this by continually evaluating scientific data and creating a consensus on treatment recommendations so member organisations could develop local guidelines.

The ILCOR recommendation for lay person CPR is DRS ABCD.

The DR CAB acronym, is mainly associated with the American Heart Association, and stands for Danger, Responsiveness, Circulation, Airway, Breathing. This sequence emphasises starting chest compressions promptly.

The change in their sequence was introduced by the AHA in 2010, based on research that suggested early, and effective chest compressions are crucial for improving outcomes in sudden cardiac arrest. The rationale is that most adult cardiac arrests are of cardiac origin, and the blood already contains oxygen that can be circulated with compressions.

In contrast, the DRS ABCD acronym, historically taught by the American Red Cross has an explicit step to "Send for help" early in the process, emphasising the importance of activating emergency medical services promptly.

The differences between these guidelines do not suggest conflicts in medical science but different strategies and emphases in instructing people.

The AHA, often focuses on a streamlined approach for professional rescuers and a simplified, compressions-focused message for lay rescuers.

American Red Cross has historically aimed to provide easily memorable sequence for both lay rescuers and those with some medical training.

“We do not recommend nor teach the mnemonic C-A-B as this sequence only applies to adult non-hypoxic cardiac arrest victims. We would not wish to alter or confuse years of teaching A- B-C, which is science-based, still valid, and still should be the approach for emergency assessment”

From personal experience with New South Wales Ambulance, having performed resuscitation on many hundreds of patients, the emphasis is on high quality, continuous CPR to keep pushing oxygen to the brain to try to prevent brain damage before medical help becomes available.

In Australia, most cardiac arrests happen in the home.

Most CPR is performed by a person who knows the victim and the airway is clear so checking for response, opening the airway and checking for normal breathing can be done in less than 15 seconds.

High quality CPR can then start with 30 compressions followed by 2 rescue breaths and do not stop until medical help arrives, or the victim tells you to.