REVIEW QUESTION

Are mechanical or manual chest compressions more effective in patients who have suffered a cardiac arrest?

TYPE OF REVIEW

A systematic review of 11 studies, including 12,944 adult participants.

RELEVANCE FOR NURSING

Traditionally, CPR has been performed manually by a human rescuer; however, in recent years mechanical chest compression devices-which provide a consistent rate and depth of depression, reduce rescuer fatigue, and free the rescuer to perform other lifesaving interventions-have received increased attention. In studies of out-of-hospital cardiac arrest, no differences in outcomes between manual and mechanical chest compressions have been reported. In studies of both out-of-hospital and in-hospital cardiac arrest, mechanical chest compression was found to be inferior to manual chest compression in the return of spontaneous circulation. However, mechanical chest compression improved hospital and 30-day survival, as well as short-term survival, in cases of in-hospital cardiac arrest. These conflicting results underscore the importance of determining the effectiveness of mechanical compression compared with manual compression and evaluating its impact on outcomes.

CHARACTERISTICS OF THE EVIDENCE

Studies were included in this review if patients suffered out-of-hospital or in-hospital cardiac arrest and received resuscitation by trained medical personnel. Events involving trauma, drowning, hypothermia, and toxic substances were excluded, as these are known to have a prognosis different from that of a cardiac arrest of no known cause. Studies were included if the intervention compared active, mechanical, automated chest compressions delivered by powered device with standard manual chest compressions delivered by a human.

The primary outcome was survival to hospital discharge with good neurologic function (defined as a cerebral performance category score of 1 or 2). Three studies reported this outcome. Of these, only one demonstrated a decrease in survival with the use of mechanical chest compression compared with manual chest compression. The remaining two studies demonstrated no difference between mechanical and manual compression. Secondary outcomes included survival to hospital admission (no studies reported a difference between interventions) and survival to hospital discharge (one study showed a survival decrease and two studies showed a survival increase with mechanical compressions, and four studies showed no difference between interventions). The quality of the evidence for each outcome was moderate to low. Meta-analysis was not conducted because of heterogeneity.

BEST PRACTICE RECOMMENDATIONS

While the evidence does not strongly support one method of chest compression over the other, when making decisions to implement (or not implement) mechanical chest compressions, it is important to consider the setting, the skill level of rescuers, and the resources available. The focus should be on minimizing the patient's time without chest compressions and minimizing delays to the use of defibrillation.

RESEARCH RECOMMENDATIONS

Future research should study the effect of mechanical chest compressions in the pediatric population and in scenarios where sustainable high-quality manual chest compressions are challenging or pose a risk to providers. Examples include CPR in a moving ambulance, situations where limited rescuers are available, during prolonged resuscitations, in the angiography suite, or during implementation of extracorporeal cardiopulmonary resuscitation.

REFERENCE