Chest Compression-only CPR
Abstract & Commentary
By John P. DiMarco, MD, PhD, Professor of Medicine, Division of Cardiology, University of Virginia, Charlottesville. Dr. DiMarco receives grant/research support from St. Jude Medical, Astellas, and Novartis, is a consultant for Medtronic and Sanofi-Aventis, and is a speaker for St. Jude Medical and Boston Scientific.
Source: Rea TD, et al. CPR with chest compression alone or with rescue breathing. N Engl J Med. 2010;363:423-433.
The dispatcher-assisted resuscitation trial (DART) tested the hypothesis that 911 dispatcher instructions to provide chest compressions only would be superior to similar instructions that included both chest compressions and rescue breathing. Calls to a 911 system for patients in cardiac arrest were eligible for inclusion in the trial if the dispatcher felt the patient was in cardiac arrest and bystander CPR had not yet been attempted. Emergency Medical Systems (EMS) in three localities, King County, Washington, Thurston County, Washington, and London, the United Kingdom, participated in the trial. Dispatchers attempted to exclude patients with arrest due to trauma, drowning, asphyxiation, or pediatric patients. Eligible patients were assigned to one of two CPR strategies in random sequence. Rescuers were instructed to either continuous chest compressions only or chest compressions plus rescue breathing in a sequence of two rescue breaths followed by 15 chest compressions. After an initial first cycle, the bystander was instructed to check for signs of life and, if none were present, he or she was to continue CPR using the same method. The primary outcome was survival to hospital discharge. Secondary outcomes were return of spontaneous circulation and neurologic status at the time of hospital discharge.
Over a four-year period, 5,525 cardiac-arrest victims were screened for eligibility. A total of 1,941 patients were randomized and found to be eligible. The mean age was 64 years, and 65% of the subjects were male. More than 70% of the cardiac arrests were thought to be cardiac in origin, and 44% were witnessed. Almost 90% of the arrests occurred in a residential location, with 9% occurring in a public location and 4% occurring in a nursing home. The mean time to initial EMS arrival was 6.6 minutes, and a shockable rhythm was identified in only 32% of the patients; the two groups were evenly matched for these characteristics. The dispatcher's instructions were followed by the rescuers in 80.5% of the subjects randomized to chest compression alone, compared to 72.7% of the patients randomized to chest compression plus rescue breathing.
There was no significant difference in the proportion of patients surviving to hospital discharge, according to randomization. Chest-compression instruction alone resulted in a 12.5% survival to hospital discharge, compared to a survival to hospital discharge of 11% for patients in the chest-compression plus rescue-breathing instruction group. A non-significant trend towards better neurologic status upon discharge was seen in the chest compression-alone group (14.4% vs. 11.5%) than in the chest compression plus rescue breathing group. Among patients with a cardiac cause for their arrest, there were slightly higher proportions with survival to hospital discharge and favorable neurologic status at discharge with chest compression alone. A reverse trend was seen in patients with noncardiac causes for cardiac arrest.
The authors conclude that dispatcher CPR instruction consisting of chest compression alone did not increase survival when compared with instructions for chest compression plus rescue breathing. However, trends for improved outcomes with chest compression alone were seen in patients with cardiac causes for arrest and patients with shockable rhythms. In view of prior findings that compression-only CPR is easier to instruct and more acceptable to many rescuers, compression-only CPR should become the standard instruction given by dispatchers.
Commentary
The need for rescue breathing during the critical early phases of CPR has recently been questioned. It has been shown that if the arrest is due to a sudden arrhythmia, blood-oxygen content is maintained for some time during compression-only CPR, and overall circulation is better if compressions are not interrupted. A CPR protocol that includes rescue breathing also is inherently more complex to teach and difficult to perform. Many rescuers are reluctant to administer mouth-to-mouth rescue breathing because of fear of infection. The data in this paper, and in an accompanying study from Sweden with similar results, support a change in policy to encourage compression-only CPR in most situations where the cardiac arrest is thought to be due to cardiac causes. Rescue breathing may remain important in cases of asphyxiation, drowning, or overdose, but these only account for small number of all cardiac arrests.
The dispatcher-assisted resuscitation trial (DART) tested the hypothesis that 911 dispatcher instructions to provide chest compressions only would be superior to similar instructions that included both chest compressions and rescue breathing.You have reached your article limit for the month. Subscribe now to access this article plus other member-only content.
- Award-winning Medical Content
- Latest Advances & Development in Medicine
- Unbiased Content