Rethinking the Unplanned ICU Admission Quality Metric in Trauma Patients

BackgroundUnplanned ICU admission (UP-ICU), a benchmark of the ACS Trauma Quality Improvement Program, is linked to increased mortality and is used to accredit trauma centers. However, it is unclear whether this reflects a causal relationship or confounding by patient physiology. We hypothesized that UP-ICU, when adjusted for patient and injury factors, would not be independently associated with higher mortality.MethodsWe conducted a retrospective case-control study of adult trauma patients admitted to a level 1 trauma center (2016-2020) with hospital length of stay (LOS) > 24 hours. Controls were selected using 1:1 propensity score matching based on injury severity (RTS, GCS, BMI, base deficit) and medical comorbidities (vascular, cardiac, respiratory, renal, and substance use disorders). The primary outcome was in-hospital mortality. The secondary outcomes included discharge to rehabilitation and LOS.ResultsAmong 7618 patients, the UP-ICU rate was 3.3% (254 patients). In the unmatched cohort, UP-ICU was associated with higher mortality than non-UP-ICU (8.6% vs 2.3%, P < 0.001). However, in the matched cohort, mortality was similar between groups (8.6% vs 7.4%, P = 0.745). Common reasons for UP-ICU included delayed intracranial hemorrhage, cardiac arrhythmia or ischemia, and respiratory distress.DiscussionIn a matched cohort, UP-ICU was not independently associated with mortality after adjustment for patient physiology, injury severity, and comorbidities. As such, UP-ICU is a quality metric that may have a role in reducing failure to rescue, as early escalation of care may allow patients to survive acute deterioration.