RT Journal Article SR Electronic T1 Perioperative SARS-CoV-2 infection and postoperative complications: a single-centre retrospective cohort study in China JF BMJ Open JO BMJ Open FD British Medical Journal Publishing Group SP e093044 DO 10.1136/bmjopen-2024-093044 VO 15 IS 5 A1 Zhan, Jia A1 Zhong, Fei A1 Dai, LingYan A1 Ma, Jue A1 Chai, YunFei A1 Zhao, XiRui A1 Chang, Lu A1 Zhang, YiDan A1 Wang, JunJiang A1 Tang, Yong A1 Zhong, Wen-Zhao A1 Zhang, Guangyan A1 Li, Le A1 Zhu, Qiang A1 Chen, ZhiHao A1 Xia, Xin A1 Peng, LiShan A1 Wu, Jing A1 Li, RuiYun A1 Li, DanYang A1 Zhu, Yan A1 Zhou, Xin A1 Wu, YiChun A1 Chen, RuiRong A1 Li, Jie A1 Li, Yong A1 Shu, HaiHua YR 2025 UL http://bmjopen.bmj.com/content/15/5/e093044.abstract AB Objective To explore the association between perioperative SARS-CoV-2 infection and the postoperative complications during the breakout of the Omicron epidemic wave.Design Observational retrospective cohort study. Multivariable logistic regression was performed to explore the association between the duration from surgery to COVID-19 diagnosis and the likelihood of postoperative complications.Setting A general hospital in China.Participants 7927 patients aged 18 years and older who underwent surgical treatment between 1 December 2022 and 28 February 2023.Primary outcome measures The outcome was a composite of postoperative adverse events that occurred within the initial 30 postoperative days.Results Of all patients, 420 (11.76%) experienced postoperative complications. Compared with No COVID-19, preoperative COVID-19 within 1 week (pre-1w) exhibited a high risk of postoperative complications (adjusted OR (aOR), 2.67; 95% CI 1.50 to 4.78), followed by patients with pre-2w (aOR, 2.14; 95% CI 1.20 to 3.80). For patients with postoperative COVID-19 within 1 week (post-1w), the aOR was 2.48 (95% CI 1.48 to 4.13), followed by patients with post-2w (aOR 1.95; 95% CI 1.10 to 3.45), and those with post-3w (aOR 2.25; 95% CI 1.27 to 3.98). The risks of postoperative complications decreased roughly with the increase of the time interval between the surgery date and SARS-CoV-2 infection. Stratification analyses suggested that perioperative COVID-19 increased the risk of postoperative complications in older patients, smokers, those with comorbidities or experiencing moderate or severe COVID-19 symptoms.Conclusions Our findings reveal a significant time-dependent relationship between perioperative COVID-19 and postoperative complications, highlighting the importance of tailored preoperative risk evaluations, enhanced postoperative surveillance, and the implementation of effective postoperative COVID-19 prevention measures.Trial registration number ChiCTR2300072473.Data are available on reasonable request.