Timing and Location of Medical Emergency Team Activation Is Associated with Seriousness of Outcome: An Observational Study in a Tertiary Care Hospital

Purpose: The medical emergency team (MET) can be activated anytime and anywhere in a hospital. We hypothesized the timing and location of MET activation are associated with seriousness of outcome. Materials and Methods: We tested for an association of clinical outcomes with timing and location using a university hospital cohort in Japan (n = 328). The primary outcome was short-term serious outcome (unplanned ICU admission after MET activation or death at scene). Results: Patients for whom the MET was activated in the evening or night-time had significantly higher rates of short-term serious outcome than those for whom it was activated during the daytime (vs. evening: adjusted OR = 2. 53, 95% CI = 1.24–5.13, P = 0.010; night-time: adjusted OR = 2.45, 95% CI = 1.09–5.50, P = 0.030). Patients for whom the MET was activated in public space had decreased short-term serious outcome compared to medical spaces (public space: adjusted OR = 0.19, 95% CI = 0.07–0.54, P = 0.0017). Night-time (vs. daytime) and medical space (vs. public space) were significantly associated with higher risks of unexpected cardiac arrest and 28-day mortality. Conclusions: Patients for whom the MET was activated in the evening/night-time, or in medical space, had a higher rate of short-term serious outcomes. Taking measures against these risk factors may improve MET performance.