Po-05-008 network meta-analysis of the comparative efficacy of double sequential external, vector-change, and standard defibrillation for refractory ventricular fibrillation out-of-hospital cardiac arrest

Double sequential external defibrillation (DSED; rapid successive shocks from two defibrillators) and vector-change defibrillation (VCD; relocating defibrillation pads anteriorly-posteriorly) have been suggested to enhance clinical outcomes for patients with ventricular fibrillation (VF) refractory of standard defibrillation (SD). This systematic review and network meta-analysis aims to evaluate the comparative efficacy of DSED, VCD, and SD for refractory VF. We conducted a systematic review and network meta-analysis synthesizing randomized controlled trials (RCTs) and comparative observational studies, which were retrieved by systematically searching: PubMed, EMBASE, Web of Science, SCOPUS, and Cochrane through November 15th, 2022. R software netmeta and netrank package (R version 4.2.0) and meta-insight software were used to pool dichotomous outcomes using odds ratio (OR) presented with the corresponding confidence interval (CI). Our protocol was prospectively published in PROSPERO with ID: CRD42022378533. Five retrospective cohorts, one RCT, one pilot RCT, and one case-control study with a total of 1,784 patients were included in our analysis. A total of 439 patients (24.6%) received DSED, 205 patients (11.5%) received VCD, and 1140 patients (n= 63.9%) received SD. In the network meta-analysis, DSED was similar to SD in survival to hospital discharge (OR: 1.14 with 95% CI [0.55, 2.83]), favorable neurological outcome (defined as modified Rankin scale (mRS) or cerebral performance category (CPC) ≤2) (OR: 1.35 with 95% CI [0.46, 3.99]), return of spontaneous circulation (ROSC) (OR: 0.90 with 95% CI [0.53;1.54]), and VF termination (OR: 1.59 with 95% CI [0.92, 2.75]). Also, VCD was similar to SD in survival to hospital discharge (OR: 1.12 with 95% CI [0.27, 4.57]), favorable neurological outcome (OR: 1.01 with 95% CI [0.18, 5.75]), ROSC (OR: 1.06 with 95% CI [0.44, 2.55]), and VF termination (OR: 1.78 with 95% CI [0.95, 3.3]). In the pairwise meta-analysis, there was no difference between DSED and SD in survival to hospital admission (OR: 1.12 with 95% CI [0.58, 2.16]). There was no difference between the use of DSED and VCD compared to SD in patients with out-of-hospital cardiac arrest secondary to refractory VF. However, the current evidence is still not conclusive, warranting further large-scale RCTs.