Background: Double external defibrillation (DED) has been used as a final effort to terminate refractory ventricular fibrillation/pulseless ventricular tachycardiac (rVF/pVT). Data surrounding time to DED and patient-centered outcomes remains limited.

Objectives: This study summarizes patient-level data from case-series of observed survival and neurologic outcomes following the use of DED for rVF/pVT among those with data regarding time to DED.

Methods: We conducted a literature search of PubMed, MEDLINE (OVID interface), and Scopus from January 1, 2000, through January 5, 2020. The literature was screened according to inclusion and exclusion criteria. Two investigators independently conducted the literature search, study selection, and data extraction.

Results: Our database search identified 3139 records. Of these, 1660 studies were eliminated following inspection of the titles and 22 studies underwent full-text screening, three included in the final analysis, describing a total of 29 cases. All studies were considered to have critical risk of bias. For the critical outcomes of survival to discharge and neurologically intact survival we identified that patients who received DED before 30 min from collapse compared to those who received DED after 30 min had better survival to discharge (33.3% [5/15] vs. 7.1% [1/14]) and neurologically intact survival (20.0% [3/15] vs. 7.1% [1/14]). Overall, 20.6% of patients survived to discharge, 13.8% with neurologically intact survival. It is noteworthy that the patients who were discharged with a CPC of 1 received two, four, five, and three standard shocks before receiving DED, and the time between their onset of cardiac arrest to their first DED attempt was recorded to be 15, 26, 26, and 32 min, respectively.

Conclusion: We would like to indicate that there is not enough evidence to suggest that early use of pre-hospital DED is associated with improved outcomes. Further research should strive to address these issues before conclusions can be drawn.