Trial of Continuous or Interrupted Chest Compressions During CPR

Study Questions:

In the setting of out-of-hospital cardiac arrest, are the outcomes better after continuous compressions with asynchronous ventilation or after compressions interrupted for ventilations?


In this cluster-randomized trial with crossover, adults with nontrauma-related cardiac arrest who were treated by emergency medical service received continuous chest compressions (intervention group) or interrupted chest compressions (control group). Patients in the intervention group received continuous chest compressions at a rate of 100 compressions per minute, with asynchronous positive-pressure ventilations delivered at a rate of 10 ventilations per minute. Patients in the control group received chest compressions interrupted with ventilations at a ratio of 30 compressions to two ventilations (the pause in compressions was not to exceed 5 seconds). The primary outcome was the rate of survival to hospital discharge. Secondary outcomes included an indicator of neurologic function.


A total of 23,711 patients were subjected to randomization. Of those, 1,129 (9%) patients in the intervention group and 1,072 (9.7%) patients in the control group survived until discharge (p = 0.07); 7% of patients in the intervention group and 7.7% of patients in the control group survived with a favorable neurologic outcome (p = 0.09). Hospital-free survival was significantly shorter in the intervention group than in the control group (p = 0.004).


In patients with out-of-hospital cardiac arrest, continuous chest compressions during cardiopulmonary resuscitation (CPR) did not result in significantly higher rates of survival with favorable neurologic function than did interrupted chest compressions.


Observational studies with out-of-hospital cardiac arrest have suggested that continuous compressions were associated with higher rates of survival than interrupted chest compressions. Interruptions reduce circulation of blood and may reduce the effectiveness of CPR. This study did not find this was the case. The authors collected CPR-process data and used an automated algorithm to confirm adherence to the protocol, which is a plus, but many cases had to be excluded due to the inability of the algorithm to confirm that patients did or did not receive continuous versus interrupted chest compressions.

Clinical Topics: Acute Coronary Syndromes, Arrhythmias and Clinical EP, Heart Failure and Cardiomyopathies, Implantable Devices, SCD/Ventricular Arrhythmias, Atrial Fibrillation/Supraventricular Arrhythmias, Acute Heart Failure

Keywords: Acute Coronary Syndrome, Arrhythmias, Cardiac, Cardiopulmonary Resuscitation, Emergency Medical Services, Heart Arrest, Heart Failure, Out-of-Hospital Cardiac Arrest, Positive-Pressure Respiration, Survival, Ventilation, AHA Annual Scientific Sessions

< Back to Listings