Surgical time, peri-operative major adverse cardiac and cerebral events and hospital stay in noncardiac surgery: insights from 7-day service implementation: A retrospective case-control study.

BACKGROUND: The 'out of hours effect' applies to patients undergoing surgery during night shifts, weekends or holidays, who face higher risks of complications and mortality. The 7-day service policy was implemented to ensure consistent healthcare delivery. OBJECTIVE: To assess the association between surgical time and incidence of major peri-operative adverse cardiac and cerebral events (MACCE) and also the length of hospital stay, and whether this has changed following the implementation of the 7-day service. DESIGN: Nested case-control study. SETTING: Single-centre university hospital. Retrospective enrolment from January 2018 to December 2021. PATIENTS: The study included 2543 cases and 10 683 controls. MAIN OUTCOME MEASURES: The primary outcome was peri-operative MACCE. Patients who developed MACCE after noncardiac surgery were compared with controls randomly selected from those without MACCE (1 : 4 ratio). RESULTS: Night-shift procedures were associated with higher incidence of peri-operative MACCE (28.7 vs. 18.2%, P < 0.001), longer hospital stays (172 vs. 155 h, P < 0.01), and higher costs (48 529 vs. 37 962 yuan, P < 0.001). In multivariable logistic regression, night-shift surgery remained independently associated with MACCE [fully adjusted odds ratio (OR) 1.54, 95% confidence interval (CI), 1.3 to 1.8; P < 0.001]. Weekend surgery was not significantly associated with MACCE after full adjustment (OR 1.15, 95% CI, 0.96 to 1.38; P = 0.13), and results were consistent in a sensitivity model including both night-shift and weekend surgery (night shift OR 1.54, 95% CI, 1.3 to 1.82, P < 0.001; weekend OR 1.17, 95% CI, 0.97 to 1.4, P = 0.09). Following implementation of the 7-day service policy, night-shift procedures decreased [16.1% prepolicy vs. 3.7% postpolicy; standardised mean difference (SMD) 0.42] and weekend procedures increased (5.5 vs. 13.3%; SMD 0.27). In the postpolicy period, weekend surgery was associated with a shorter hospital stay (139 vs. 160 h, P < 0.001) without an increase in MACCE (18.7 vs. 19.4%, P = 0.53). CONCLUSION: Night-shift surgery was an independent risk factor for peri-operative MACCE in noncardiac surgery patients. The 7-day service policy reduced night-shift procedures and increased those at weekends, without increasing the risk of MACCE. It was also associated with shorter hospital stays. TRIAL REGISTRATION: Chinese Clinical Trial Registry identifier: ChiCTR1900024645.