Tiered escalation response systems in practice: A post hoc analysis examining the workload implications

Many rapid response systems now have multiple tiers of escalation in addition to the traditional single tier of a medical emergency team. Given that the benefit to patient outcomes of this change is unclear, we sought to investigate the workload implications of a multitiered system, including the impact of trigger modification.

The study design incorporated a post hoc analysis using a matched case-control dataset.

The study setting was an acute, adult tertiary referral hospital.

Cases that had an adverse event (cardiac arrest or unanticipated intensive care unit admission) or a rapid response team (RRT) call participated in the study. Controls were matched by age, gender, ward and time of year, and no adverse event or RRT call. Participants were admitted between May 2014 and April 2015.

The main outcome measure were the number of reviews, triggers, and modifications across three tiers of escalation; a nurse review, a multidisciplinary review (MDT-admitting medical team review), and an RRT call.

There were 321 cases and 321 controls. Overall, there were 1948 nurse triggers, of which 1431 (73.5%) were in cases and 517 (26.5%) in controls, 798 MDT triggers (660 [82.7%] in cases and 138 [17.3%] in controls), and 379 RRT triggers (351 [92.6%] in cases and 28 [7.4%] in controls). Per patient per 24 h, there were 3.03 nurse, 1.24 MDT, and 0.59 RRT triggers. Accounting for modifications, this reduced to 2.17, 0.88, and 0.42, respectively. The proportion of triggers that were modified, so as not to trigger a review, was similar across all the tiers, being 28.6% of nurse, 29.6% of MDT, and 28.2% of RRT triggers. Per patient per 24 h, there were 0.61 nurse reviews, 0.52 MDT reviews, and 0.08 RRT reviews.

Lower-tier triggers were more prevalent, and modifications were common. Modifications significantly mitigated the escalation workload across all tiers of a multitiered system.