Impact of hospitalization duration before medical emergency team activation: A retrospective cohort study

The rapid response system has been implemented in many hospitals worldwide and, reportedly, the timing of medical emergency team (MET) attendance in relation to the duration of hospitalization is associated with the mortality of MET patients. We evaluated the relationship between duration of hospitalization before MET activation and patient mortality. We compared cases of MET activation for early, intermediate, and late deterioration to patient characteristics, activation characteristics, and patient outcomes. We also aimed to determine the relationship, after adjusting for confounders, between the duration of hospitalization before MET activation and patient mortality.

We retrospectively evaluated patients who triggered MET activation in general wards from March 2009 to February 2015 at the Asan Medical Center in Seoul. Patients were categorized as those with early deterioration (less than 2 days after admission), intermediate deterioration (2-7 days after admission), and late deterioration (more than 7 days after admission) and compared them to patient characteristics, activation characteristics, and patient outcomes.

Overall, 7114 patients were included. Of these, 1793 (25.2%) showed early deterioration, 2113 (29.7%) showed intermediate deterioration, and 3208 (45.1%) showed late deterioration. Etiologies of MET activation were similar among these groups. The clinical outcomes significantly differed among the groups (intensive care unit transfer: 34.1%, 35.6%, and 40.4%; p < 0.001 and mortality: 26.3%, 31.5%, and 41.2%; p < 0.001 for early, intermediate, and late deterioration, respectively). Compared with early deterioration and adjusted for confounders, the odds ratio of mortality for late deterioration was 1.68 (1.46-1.93).

Nearly 50% of the acute clinically-deteriorating patients who activated the MET had been hospitalized for more than 7 days. Furthermore, they presented with higher rates of mortality and ICU transfer than patients admitted for less than 7 days before MET activation and had mortality as an independent risk factor.