Rapid Response Systems as Secondary Responders to In-Hospital Clinical Deterioration: A Four-Year Observational Study

Background: In-hospital cardiac arrest (IHCA) is a major cause of preventable inpatient mortality, especially in low- and middle-income countries (LMICs) where rapid response systems (RRS) are still developing. Evidence regarding RRS performance in Indonesia is limited. This study evaluated the performance and operational challenges of an institutional RRS over four years at a large tertiary referral hospital in Jakarta.Objective: This study aimed to determine the proportion of immediate survival following RRS activation and to investigate secondary outcomes, including the association between activation indications and mortality, and system-level barriers.Methods: This retrospective observational cohort study included all inpatient RRS activations at Cipto Mangunkusumo National General Hospital (RSCM), Jakarta, Indonesia, from January 1, 2021, to December 31, 2024. Data from the hospital’s RRS registry were analyzed for activation triggers, interventions, immediate outcomes, and operational issues.Results: Among 246,367 inpatient admissions, there were 5,900 eligible inpatient RRS activations, yielding an activation rate of 23.9 per 1,000 admissions. Immediate survival occurred in 4,763 (80.7%) events, while 1,137 (19.3%) patients did not survive. Cardiac arrest (8.0%) and respiratory arrest (6.5%) were the strongest predictors of non-survival odds ratio (OR) 48.17 and 27.13 vs. red early warning score (EWS) reference, both p