Observational studyBMJ open2026
Association between preoperative COVID-19 and major postoperative pulmonary complications: a multicentre observational cohort study in China.
Observational study in BMJ open, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
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Authors and funding
16 authors.
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Abstract
objectiveTo evaluate the relationship between preoperative COVID-19 infection and major postoperative pulmonary complications (PPC) risk after major elective surgeries during the Omicron wave.
designA multicentre, prospective, observational cohort study.
settingFour tertiary medical centres in Beijing, China.
participantsAll adult patients who underwent major elective surgeries under general anaesthesia from 30 December 2022 to 18 May 2023 were screened for eligibility. A total of 3211 patients were included. PRIMARY AND SECONDARY MEASURES: The primary outcome was 30-day major PPC, defined as pneumonia, acute respiratory distress syndrome or unexpected postoperative ventilation. The secondary outcomes included length of hospital stay (LOS), reoperation and mortality.
resultsMajor PPC occurred in 3.5% of patients with preoperative COVID-19 and 3.3% of those without. Inverse probability of treatment weighting-adjusted analysis showed no significant association between preoperative COVID-19 within 12 weeks and PPC risk (adjusted OR, 0.89; 95% CI 0.69 to 1.13). However, multivariable analysis revealed that COVID-19 infection within 3 weeks was independently associated with an increased PPC risk (OR, 3.44; 95% CI 1.37 to 8.68). Cardiothoracic surgery (OR, 12.47; 95% CI 8.11 to 19.17) and longer duration of surgery (OR, 1.24 per hour; 95% CI 1.13 to 1.37) were significant risk factors. In the cardiothoracic subgroup, PPC risk was significantly elevated within 7 weeks of infection. No significant differences were observed in LOS, reoperation rates or mortality between patients with and without preoperative COVID-19 infection.
conclusionsPreoperative COVID-19 infection within 12 weeks was not associated with an increased overall risk of major PPC during the Omicron wave. Although very short infection-to-surgery intervals and cardiothoracic surgery showed exploratory signals of higher risk, these findings should be interpreted cautiously and support an individualised approach to perioperative risk assessment. TRIAL REGISTRATION NUMBER: ChiCTR2200067250.
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