Risk factors for pulmonary complications after colorectal surgery: a Japanese multicenter study

Abstract Purpose: Pulmonary complications (PC) are a serious condition with a 20% mortality rate. However, few reports have examined risk factors for PC after colorectal surgery. This study investigated the frequency, characteristics, and risk factors for PC after colorectal cancer surgery. Methods: Between January 2016 and December 2022, we retrospectively reviewed 3979 consecutive patients who underwent colorectal surgery in seven participating hospitals. Patients were divided into patients who experienced PC (PC group, n=54) and patients who did not (Non-PC group, n=3925). Clinical and pathological features were compared between groups. Results: Fifty-four patients (1.5%) developed PC, of whom 2 patients (3.7%) died due to PC. Age was greater (80 years vs 71 years; p<0.001), frequency of chronic obstructive pulmonary distress was greater (9.3% vs 3.2%; p=0.029), performance status was poorer (p<0.001), body mass index was lower (18 kg/m2 vs 22 kg/m2; p<0.001), frequency of open surgery was greater (24.1% vs 9.3%; p<0.001), and blood loss was greater (40 mL vs 22 mL; p<0.001) in the PC group. Multivariate analysis of PC revealed male sex (odds ratio [OR] 1.845, 95% confidence interval [CI] 1.023–3.329; p=0.041), high age (OR 3.434, 95%CI 1.941–6.075; p<0.001) and poor performance status (OR 4.144, 95%CI 2.318–7.408; p<0.001) as independent predictors of PC. Conclusion: Our study revealed male sex, greater age, and poorer ASA-PS as factors associated with development of PC, and suggested that pre- and postoperative rehabilitation and pneumonia control measures should be implemented for patients at high risk of PC.