Intra-Arrest Transport, ECPR, and Invasive Strategy in Out-of-Hospital Cardiac Arrest

In patients who experience refractory, out-of-hospital cardiac arrest (OHCA), the bundle of early intra-arrest transport, extracorporeal cardiopulmonary resuscitation (ECPR), and invasive assessment and treatment was not associated with significant improvements in survival with neurologically favorable outcomes at 180 days, compared with the use of standard resuscitation. The findings were published in the Journal of the American Medical Association (JAMA).

Patients with OHCA typically experience poor outcomes and become a significant socioeconomic burden to society. It remains unclear whether intra-arrest transport, ECPR, and immediate invasive assessment and treatment can be beneficial. The objective of the current study was to establish whether use of an early invasive approach in adults with refractory OHCA can improve neurologically favorable survival.

A single-center, randomized clinical trial (ClinicalTrials.gov identifier: NCT01511666) was conducted in Prague, Czech Republic. The study enrolled adult patients with a witnessed OHCA of presumed cardiac origin without a return of spontaneous circulation. The primary study outcome was survival with a good neurologic outcome (which was defined as a Cerebral Performance Category [CPC] score of 1 to 2) at 180 days following randomization. Secondary study outcomes included neurologic recovery at 30 days (defined as a CPC score of 1 to 2 at any time within the first 30 days) and cardiac recovery at 30 days (defined as no need for pharmacologic or mechanical cardiac support for 24 hours or more).

A total of 256 participants were enrolled in the study between March 2013 and October 2020, with 124 in the invasive-strategy group and 132 in the standard-strategy group. In the invasive-strategy arm, mechanical compression was started, followed by intra-arrest transport to a cardiac center for ECPR and immediate invasive assessment/ treatment. In the standard-strategy arm, regular advanced cardiac life support was continued onsite.

All of the participants were observed until death or day 180 (with the last patient follow-up ending in March 2021). The median patient age was 58 years; 17% of the participants were women. The trial was terminated at the recommendation of the data and safety monitoring board when prespecified criteria for futility were fulfilled. Overall, all of the patients completed the study.

The findings revealed that in the main analysis, 31.5% of participants in the invasive-strategy arm vs 22.0% of those in the standard-strategy arm survived to 180 days with a good neurologic outcome (odds ratio [OR], 1.63 [95% CI, 0.93 to 2.85]; difference, 9.5% [95% CI, –1.3% to 20.1%]; P =.09).

At 30 days, neurologic recovery was observed in 30.6% of those in the invasive-strategy group and 18.2% of participants in the standard-strategy group (OR, 1.99 [95% CI, 1.11 to 3.57]; difference, 12.4% [95% CI, 1.9% to 22.7%]; P =.02). Further, cardiac recovery was observed in 43.5% of participants of those in the invasive-strategy arm and 34.1% of participants in the standard-strategy arm (OR, 1.49 [95% CI, 0.91 to 2.47]; difference, 9.4% [95% CI, –2.5% to 21%]; P =.12).

Bleeding was reported more often in the invasive-strategy group than in the standard-strategy group (31% vs 15%, respectively).

Study limitations included its single-center design and limited patient enrollment. Additionally, a priori scenarios of expected benefit provided by the invasive approach were not attained, probably because of higher-than-expected survival among those in the standard-strategy group.

The researchers concluded that “…the trial was possibly underpowered to detect a clinically relevant difference,” which may have been responsible for the results.

Disclosure: One of the study authors has declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of the author’s disclosures. 

Reference  

Belohlavek J, Smalcova J, Rob D, et al; Prague OHCA Study Group. Effect of intra-arrest transport, extracorporeal cardiopulmonary resuscitation, and immediate invasive assessment and treatment on functional neurologic outcome in refractory out-of-hospital cardiac arrest: a randomized clinical trial.  JAMA. Published online February 22, 2022. doi:10.1001/jama.2022.1025