Effect of after-hours presentation in ruptured abdominal aortic aneurysm.

Objective: Ruptured abdominal aortic aneurysms (RAAAs) are surgical emergencies that require immediate and expert treatment. It has been unclear whether presentation during evenings and weekends, when "on call" teams are primarily responsible for patient care, is associated with worse outcomes. Our objective was to evaluate the outcomes of patients presenting with RAAAs after-hours vs during the workday.

Methods: A retrospective cohort study of all RAAAs in Nova Scotia between 2005 and 2015 was performed through linkage of administrative databases. Patients who had presented to the hospital with RAAAs during the workday (Monday through Friday, 6 am to 6 pm) were compared with those who had presented after-hours (6 pm to 6 am during the week and on weekends). The baseline and operative characteristics were identified for all patients through the available databases and a review of the medical records. Mortality before surgery, 30-day mortality, and operative mortality were compared between groups using multivariable logistic regression, adjusting for factors clinically significant on univariable analysis.

Results: A total of 390 patients with RAAAs were identified from 2005 to 2015, of whom 205 (53%) had presented during the workday and 185 (47%) after-hours. The overall chance of survival (OCS) was 45% overall, 49% if admitted to hospital, and 64% if surgery had been performed. During the workday, the OCS was 43% overall, 48% if admitted to hospital, and 67% if surgery had been performed. After-hours, the OCS was 46% overall, 49% if admitted to hospital, and 61% if surgery had been performed. Mortality before surgery was increased for patients who had presented to the hospital during the workday compared with after-hours (36% vs 26%; P = .04). The 30-day mortality (57% vs 54%; P = .62), rates of operative management (63% vs 72%; P = .06), and operative mortality (33% vs 39%; P = .33) were similar between the workday and after-hours groups (57% vs 54%; P = .06). After adjusting for significant clinical variables, the patients who had presented with RAAAs after-hours had had a similar odds of dying before surgery (odds ratio [OR], 0.64; 95% confidence interval [CI], 0.41-1.03), operative management (OR, 1.47; 95% CI, 0.93-2.31), 30-day mortality (OR, 0.98; 95% CI, 0.63-1.51), and operative mortality (OR, 1.33; 95% CI, 0.78-2.26). In the subgroup of patients presenting to a hospital with endovascular capabilities, patients presenting after-hours had had similar odds of 30-day mortality (OR, 1.07; 95% CI, 0.57-2.02), and operative mortality (OR, 1.14; 95% CI, 0.58-2.23).

Conclusions: We found that patients presenting to the hospital with RAAAs after-hours did not have increased adjusted odds of mortality before surgery, operative management, 30-day mortality, or operative mortality.