Outcome of Hypotensive Trauma Patients by Time and Day of Arrival.

Background: Although most studies of trauma patients have not demonstrated a "weekend" or "night" effect on mortality, outcomes of hypotensive (systolic blood pressure <90 mm Hg) patients have not been studied. We sought to evaluate whether outcomes of hypotensive patients were associated with admission time and day.

Methods: We retrospectively analyzed patients from Pennsylvania Level 1 and Level 2 trauma centers with systolic blood pressure of <90 mm Hg over 5 y. Patients were stratified into four groups by arrival day and time: Group 1, weekday days; Group 2, weekday nights; Group 3, weekend days; and Group 4, weekend nights. Patient characteristics and outcomes were compared for the four groups. Adjusted mortality risks for Groups 2, 3, and 4 with Group 1 as the reference were determined using a generalized linear mixed effects model.

Results: After exclusions, 27 trauma centers with a total of 4937 patients were analyzed. Overall mortality was 44%. Compared with patients arriving during the day (Groups 1 and 3), those arriving at night (Groups 2 and 4) were more likely to be younger, to be male, to have lower Glasgow Coma Scale scores and blood pressures, to have penetrating injuries, and to die in the emergency room. Controlled for admission variables, odds ratios (95% confidence intervals) for Groups 2, 3, and 4 were 0.92 (0.72-1.17), 0.89 (0.65-1.23), and 0.76 (0.56-1.02), respectively, for mortality with Group 1 as reference.

Conclusions: Patients arriving in shock to Pennsylvania Level 1 and Level 2 trauma centers at night or weekends had no increased mortality risk compared with weekday daytime arrivals.