The introduction of a rapid response system in acute hospitals: A pragmatic stepped wedge cluster randomised controlled trial

Aim: Deterioration of hospitalised patients is often missed, misinterpreted, and mismanaged. Rapid Response Systems (RRSs) have been proposed to solve this problem. This study aimed to investigate the effect of an RRS on the incidence of unexpected death, cardiac arrest with cardiopulmonary resuscitation (CPR), and unplanned intensive care unit (ICU) admission. Methods: We conducted a stepped wedge cluster randomised controlled trial including 14 Belgian acute care hospitals with two medical and two surgical wards each. The intervention comprised a standardised observation and communication protocol including a pragmatic medical response strategy. Comorbidity and nurse staff levels were collected as potential confounders. Results: Twenty-eight wards of seven hospitals were studied from October 2013 until May 2015 and included in the final analysis. The control group contained 34,267 patient admissions and the intervention group 35,389. When adjusted for clustering and study time, we found no significant difference between the control and intervention group in unexpected death rates (1.5 vs 0.7/1000, OR 0.82, 95% CI 0.34-1.95), cardiac arrest rates (1.3 vs 1.0/1000, OR 0.71, 95% CI 0.33-1.52) or unplanned ICU admissions (6.5 vs 10.3/1000, OR 1.23, 95% CI 0.91-1.65). Conclusion: Our intervention had no significant effect on the incidence of unexpected death, cardiac arrest or unplanned ICU admission when adjusted for clustering and study time. We found a lower than expected baseline incidence of unexpected death and cardiac arrest rates which reduced the statistical power significantly in this study.