Background: While rapid response systems have been widely implemented, their impact on patient outcomes remains unclear. Further understanding of their components-including medical emergency team triggers, medical emergency team member composition, additional roles in patient care beyond responding to medical emergency team events, and their involvement in "Do-Not-Resuscitate" order placement-may elucidate the relationship between rapid response systems and outcomes.
Objective: To explore how recent studies have examined rapid response system components in the context of relevant adverse patient outcomes, such as in-hospital cardiac arrests and hospital mortality.
Design: Scoping review.
Methods: PubMed, CINAHL, and Embase were searched for articles published between November 2014 and June 2022. Studies mainly focused on rapid response systems and associations with in-hospital cardiac arrests were considered. The following were extracted for analysis: study design, location, sample size, participant characteristics, system characteristics (including medical emergency team member composition, additional system roles outside of medical emergency team events), medical emergency team triggers, in-hospital cardiac arrests, and hospital mortality.
Results: Thirty-four studies met inclusion criteria. While most studies described triggers used, few analyzed medical emergency team trigger associations with outcomes. Of those, medical emergency team triggers relating to respiratory abnormalities and use of multiple triggers to activate the medical emergency team were associated with adverse patient outcomes. Many studies described medical emergency team member composition, but the way composition was reported varied across studies. Of the seven studies with dedicated medical emergency team members, six found their systems were associated with decreased incidence of in-hospital cardiac arrests. Six of seven studies that described additional medical emergency team roles in educating staff in rapid response system use found their systems were associated with significant decreases in adverse patient outcomes. Four of five studies that described proactive rounding responsibilities reported found their systems were associated with significant decreases in adverse patient outcomes. Reporting of rapid response system involvement in "Do-Not-Resuscitate" order placement was variable across studies.
Conclusions: Inconsistencies in describing rapid response system components and related data and outcomes highlights how these systems are complex to a degree not fully captured in existing literature. Further large-scale examination of these components across institutions is warranted. Development and use of robust and standardized metrics to track data related to rapid response system components and related outcomes are needed to optimize these systems and improve patient outcomes.
Keywords: Heart arrest; Hospital mortality; Hospital rapid response team; Review.