Abstract: Objective  To explore the predictive value of postoperative drainage volume and lung function for pulmonary complications (PPCs) after thoracoscopic lobectomy (VATSL) in patients with non-small cell lung cancer (NSCLC). Methods The clinical data of 80 NSCLC patients with VATSL treated in Suzhou Hospital of Integrated Traditional Chinese and Western Medicine from June 2017 to June 2022 were collected.According to the occurrence of postoperative PPCs,patients were divided into the occurrence group and the non-occurrence group.Lung function indexes of all NSCLC patients were examined one week before surgery,and postoperative drainage volume of 3 days after operation was recorded.The influencing factors of PPCs after VATSL were analyzed by Logistic regression,and the predictive value of postoperative drainage volume and lung function on PPCs after VATSL in NSCLC patients was analyzed according to ROC curve. Results After VATSL,there were 57 cases without PPCs and 23 cases with PPCs,the incidence of PPCs was 28.75%.There was no significant differencein gender,age,BMI,operation time,intraoperative blood loss,length of hospital stay,clinical stage,history of diabetes,history of hypertension,smoking history and lung function between the two groups [vital capacity (VC),forced vital capacity (FVC),forced expiratory volume in the first second (FEV1),FEV1/FVC,maximum volume of gas (MVV)] (P>0.05).The peak expiratory flow (PEF) level in the occurrence group was lower than that in the non-occurrence group,and the drainage flow of 3 days after operation was higher than that in the non-occurrence group (P<0.05).Logistic regression analysis showed that PEF and drainage volume of 3 days after operation were independent risk factors for PPCs after VATSL in NSCLC patients (P<0.05).ROC analysis showed that the AUC values of PPCs after PEF and drainage volume of 3 days after operation assessment of VATSL in NSCLC patients were 0.788 and 0.815,respectively,and 95%CI were 0.682-0.871 and 0.713-0.893.The combined prediction of AUC was 0.908 and 95%CI was 0.823-0.961. Conclusion Both postoperative drainage volume and PEF have certain reference value for predicting the occurrence of PPCs after VATSL in NSCLC patients,and the combined value is higher for predicting the occurrence of PPCs after VATSL.

Key words: postoperative diversion flow, lung function, non-small cell lung cancer, thoracoscopic lobectomy, acute respiratory distress syndrome, prognosis