Association of surgical procedure start time and post operative outcomes following emergency abdominal surgery at Mulago National Referral Hospital - A five year retrospective cohort study

Abstract

Background: Emergency abdominal surgeries are among the high-risk procedures with unacceptably high morbidity and mortality rates in the whole world, despite advances in surgical techniques and intensive care services. Studies have shown mixed results for morbidity and mortality outcomes in surgical procedures performed in out of hours (nightshift) but this association is yet to be evaluated in Uganda. Objective: We aimed to evaluate the association between time of day and outcome of Emergency abdominal surgical procedures done at Mulago national referral hospital over a five-year period. Method: We conducted a retrospective cohort analysis of file records of patients, aged 13 years and above who had emergency abdominal surgery performed at Mulago National referral hospital from 1st January 2016 to 31st of December 2020. The data extracted from the files included: Surgery start time, patient demographics, and comorbidities, details of the emergency abdominal procedure undertaken, intraoperative adverse events and outcomes (in-hospital mortality and morbidity). We used logistic regression to assess association between emergency abdominal surgery start time and outcomes. All analysis were conducted using STATA version 16, with a significance level set at p<0.05 Results: A total of 1370 patient charts for emergency abdominal surgeries were analyzed. Cases operated during the day were 1116 (81.5%) compared to the 254 cases (18.5%) operated during the night hours. The male cases were 974 (71.2%) and the females, 394 (28.8%). In-hospital postoperative complications occurred in 205 cases (15.0%) and the in-hospital mortality rate for this cohort was 11.9% (n=163 cases). Emergency abdominal surgeries done during the night had 7.14 times higher odds of dying in the hospital compared to those done during daytime (adjusted OR= 7.14, p<0.0001). Nighttime surgery was significantly associated with higher complication rates compared to day-time emergency abdominal surgery (Adjusted OR = 1.69 P=0.01) Surgical site infection was the commonest post-operative complication 14.6% (n=201) Conclusion: Night time emergency abdominal surgeries at Mulago national referral hospital, Uganda have higher odds of in hospital morbidity and mortality.