Automated External Defibrillators for In-Hospital Cardiac Arrest: A Systematic Review

Automated external defibrillators (AEDs) improve survival after out-of-hospital cardiac arrest, but their role in in-hospital cardiac arrest (IHCA) remains uncertain. This systematic review evaluates whether ward-accessible AED capability prior to code blue team arrival improves survival and neurologic outcomes compared with standard resuscitation systems.

Six databases were searched. Eligible studies compared AED use to manual defibrillation in IHCA outside specialized areas. Primary outcome was survival with favorable neurological status (CPC 1-2, mRS 0-3, or no deterioration from baseline). Secondary outcomes included ROSC, survival at 24 hours, survival to discharge, 30-day survival, CPR quality, and timing metrics. Three independent reviewers performed study selection, data extraction, and risk-of-bias assessment. Due to substantial heterogeneity, results were synthesized descriptively.

Six reports from five unique study cohorts met inclusion criteria (total screened = 5,510). Neurologically favorable survival was inconsistent. One study reported improved outcomes following a combined AED-and-training intervention, whereas the largest multicentre cohort found no significant difference in neurological disability among survivors (adjusted relative risk 1.01, 95% CI 0.93-1.09). ROSC and survival to discharge were not consistently improved. Only one study directly quantified AED-associated compression pauses, and effects on time to defibrillation varied by setting.

Available evidence is insufficient to determine whether routine ward-level AED deployment improves IHCA outcomes. Included studies were observational and heterogeneous and CPR quality and training were incompletely characterized. Potential benefit from earlier defibrillation in shockable rhythms must be weighed against possible compression interruptions. Contemporary comparative studies are needed.