Extracorporeal vs Conventional CPR for Out-of-Hospital Cardiac Arrest

Extracorporeal cardiopulmonary resuscitation (CPR) of patients experiencing out-of-hospital cardiac arrest was not found to be associated with increased survival when compared with conventional CPR, according to study results published in the European Heart Journal.

The registry used in this study included cases of out-of-hospital cardiac arrest that had occurred in Paris and 3 suburbs. After an emergency call was made, basic and advanced life support was provided by emergency medical services. Data were collected using Utstien templates during the emergency event and included demographic characteristics, cardiac event settings, prehospital care, initial shock rhythm, and protocol used during resuscitation.

Spontaneous circulation following cardiac arrest was defined as pulse or blood pressure returning after an initial resuscitation. Extracorporeal CPR was used in the absence of a return of spontaneous circulation or when cardiac arrest occurred again. Extracorporeal membrane oxygenation was used at the recommendation of a physician. Data from the hospital stay included coronary angiography, date of death or discharge, and neurological status.

Of the 13,191 patients with out-of-hospital cardiac arrests in whom resuscitation was attempted, 4% received an attempted extracorporeal-CPR implantation, 89% of which succeeded. Patients in the group that received extracorporeal vs conventional CPR were younger (50 years vs 66 years, respectively; P <.0001), included more men (84% vs 67%, respectively; P <.001), had an initial shockable rhythm (69% vs 25%, respectively; P <.001), had fewer returns of spontaneous circulation (26% vs 38%, respectively; P <.001), and more frequently had CPR lasting >30 minutes (99% vs 77%, respectively; P <.001). Overall survival to hospital discharge was comparable between the 2 groups (8.4% vs 8.6%, respectively; P =.91). Extracorporeal CPR was not associated with increased survival (odds ratio [OR], 1.3; P =.24) or better neurological outcomes (OR, 1.0; P =.96). 

In the extracorporeal-CPR group, 3 factors were found to be independently associated with survival: initial shockable rhythm (OR, 3.9; P =.005), a transient return of spontaneous circulation during initial resuscitation (OR, 2.3; P =.03), and prehospital extracorporeal membrane oxygenation implantation (OR, 2.9; P =.002). A total of 8% of patients who received extracorporeal-CPR were discharged, and 84% of these patients had favorable neurological outcomes.

Study limitations include the inability to assess causality due to its observational nature, and the lack of assessment of complications related to implantation, of quality-of-life, and of cost analysis.

“Extracorporeal-CPR was not associated with improved outcome compared with conventional-CPR. Extracorporeal-CPR might be best reserved for patients with features associated with better extracorporeal-CPR outcomes, ie, an initial shockable rhythm and transient return of spontaneous circulation,” concluded the study authors.

Reference

Bougouin W, Dumas F, Lamhaut L, et al. Extracorporeal cardiopulmonary resuscitation in out-of-hospital cardiac arrest: a registry study. [published online Oct. 31, 2019]. Eur Heart J. doi: 10.1093/eurheartj/ehz753