Outcomes of Daytime and Night-Time Appendectomies: A Systematic Review and Meta-Analysis

Background: Acute appendicitis is a common surgical emergency characterized by appendix inflammation. Surgery remains the gold standard for treatment with laparoscopy gaining in popularity. However, the optimal timing for appendectomy remains unclear. We are not aware of studies evaluating potential differences in clinical outcomes among appendectomies performed during the daytime and at night. Methods: We followed the PRISMA guidelines and searched the ScienceDirect, Medline, and Google Scholar databases for studies published in English before June 2023. We included prospective and retrospective studies reporting appendectomy outcomes. We categorized the appendectomy procedure times as daytime or night-time based on each study's definitions. We extracted baseline characteristics and outcomes and assessed the quality of the studies included using the Newcastle-Ottawa Scale. We calculated pooled risk ratios (RRs) and weighted mean differences (WMDs) using random-effects models; and, we assessed heterogeneity using the I-2 statistic. Results: We analyzed data from 12 studies for systematic review (n=19,183) including daytime (n=11,839) and night-time (n=7344) appendectomies. For the meta-analysis, we included 9 studies, that evaluated outcomes such as mortality (pooled RR, 0.44; 95% CI, 0.09-2.01; I-2=43.7%; P=0.11), hospital stay (WMD, -0.02; 95% CI, -0.24 to 0.20; I-2=93.3%; P <0.001), and complications (pooled RR, 0.96; 95% CI, 0.64-1.45; I 2=65.1%; P =0.02). We found similar mortality rates, hospital stay lengths, and complications for the appendectomies, regardless of the time of day of the operation. The baseline characteristics of the patients were also similar, except for the duration of symptoms and the presence of an appendiceal abscess. Conclusion: Our results showed that the timing of an appendectomy (daytime vs. night-time) does not significantly affect its outcomes. Surgeon availability or fatigue, and patient severity may not significantly impact the operation results. Standardized protocols and perioperative care ensure consistent outcomes.