Enhancing Patient Safety in Refractory Ventricular Fibrillation: A Systematic Review of Double Sequential and Vector...

Background/Objectives: Ventricular fibrillation (VF) is the most common shockable rhythm in cardiac arrest, yet refractory VF (RVF), defined as persistent VF after ≥three failed defibrillation attempts, poses a significant challenge. Two alternative strategies, double sequential external defibrillation (DSED) and vector change (VC) defibrillation, aim to enhance defibrillation success where conventional methods fail. This review evaluates the clinical feasibility, safety, and implementation barriers of DSED and VC in RVF cases. Methods: A systematic review was conducted following PRISMA 2020 guidelines. PubMed, Scopus, and CINAHL databases were searched for studies published between January 2015 and August 2025. Eligible studies included adult RVF patients treated with DSED or VC. Outcomes assessed included implementation barriers, safety concerns, and methodological limitations. Study quality was evaluated using the Newcastle-Ottawa Scale and the Cochrane RoB 2 tool. Results: Sixteen studies met the inclusion criteria. Identified barriers were grouped into practical and methodological categories. Practical barriers included the need for dual defibrillators and pads, delays in shock coordination, inconsistent protocols, equipment compatibility issues, and dependence on trained personnel. Methodological barriers included small sample sizes, retrospective designs, inconsistent RVF definitions, and incomplete reporting of neurological outcomes. Conclusions: DSED and VC defibrillation may offer potential benefits in managing RVF, but their use is hindered by significant practical and methodological barriers. Due to the limited number of randomized trials, further high-quality studies with standardized definitions and safety endpoints are needed to clarify their clinical utility and inform implementation.