Continuous chest compressions during CPR do not improve survival compared to interrupted chest compressions, according to a recently published trial. In out-of-hospital cardiac arrests attended by emergency medical services, there was no difference in survival until discharge of patients receiving continuous chest compressions with positive-pressure ventilation compared to those receiving compressions interrupted for ventilation at […]
Continuous chest compressions during CPR do not improve survival compared to interrupted chest compressions, according to a recently published trial.
In out-of-hospital cardiac arrests attended by emergency medical services, there was no difference in survival until discharge of patients receiving continuous chest compressions with positive-pressure ventilation compared to those receiving compressions interrupted for ventilation at a rate of 30 to 2.
This finding jars with guidelines newly introduced by the American Heart Association that emergency medical services should initiate resuscitation with three initial periods of 200 continuous chest compressions with passive oxygen insufflation.
Professor Hugh Grantham of the Australian Resuscitation Council thinks that had this knowledge been at hand a year ago, the AHA would not have changed its recommendations.
“‘If it ain’t broke don’t fix it’ is a very strong factor when deciding on guidelines since changing them decreases compliance significantly; we might do harm by changing,” said the Professor of Paramedics at Flinders University.”
“As we speak, I’m on my way to Melbourne to help write the Australian guidelines; traditional CPR as we know and love it is not going to change in 2015,” he said. “All health professionals are taught the same deal so that it all meshes smoothly. Having said that, there is nothing magical about the number 30.”
The NEJM study looked at 23,711 CPR events for out-of-hospital cardiac arrest performed by 114 paramedic agencies across in North America. Emergency Paramedic agencies were cluster randomized with cross-over to deliver the intervention protocol or the control protocol.
The intervention involved delivering uninterrupted chest compressions and continuous positive-pressure ventilation cycles of 10 per minute. In the control protocol, 30 compressions were followed by a pause to allow for two ventilations cycles.
Survival until discharge was 9.0% in the intervention group and 9.7% in the control group (95% CI; ?1.5 to 0.1; p=0.07). Over three quarters of patients in both groups had favourable neurologic function as assessed on the modified Rankin scale. There was no significant difference between the groups in the average quality of care administered before or after admission to hospital.
In fact, the study also reported no significant difference between the groups in the proportion of each minute taken up by compressions. However, in cases of bystander-administered CPR where no ventilator typically available, prolonged interruption for mouth-to-mouth ventilation can significantly reduce compression rate. And bystanders are often unwilling to perform CPR because of concerns with hygiene during mouth-to-mouth ventilation.
In the advertisements in the UK, the public are now taught ‘hard and fast’ hands-only CPR by cinematic gangster Vinnie Jones. “We should, be permissive of compression-only CPR for bystanders if it can encourage more bystanders to engage,” said Professor Grantham. “If the alternative is that or nothing, then that is definitely a lot better. We will be considering these options, but my personal gut feeling is that we’re unlikely to be changing Australian guidelines.”
Professor Grantham said that it was important to note the high rate of good neurologic outcomes reported in the NEJM study, as people are disproportionately afraid of this when considering receiving or giving CPR. “Regardless of age, if you survive a cardiac arrest, your life expectancy is pretty good. You go back to where you were,” he said.
Some people end up with tolerable memory impairments but a very small proportion end up on a ventilator in a brain-damage ward, “I actually go look after that ward for Adelaide every now and again. And I can change all the tracheal tubes on that ward in 50 minutes single-handed,” said Professor Grantham. “My point is if it was such a problem you’d have a hospital full, not ten beds.”
The research was carried out by the Resuscitation Outcomes Consortium (ROC) which Professor Grantham described as very thorough
NEJM 2015 online Nov 9
http://www.nejm.org/doi/full/10.1056/NEJMoa1509139
