Abstract: Objective To explore the correlation between preoperative airway preparation and postoperative day 1 drainage volume in patients undergoing radical esophagectomy and the occurrence of postoperative pulmonary complications.Methods Analyzing the clinical data of esophageal cancer 147 patients who underwent thoracoscopic and laparoscopic radical surgery from January 2022 to June 2024,they were divided into PPCs group and non-PPCs group based on whether PPCs occurred postoperatively.Clinical data of the two groups were compared.Multivariate logistic regression analysis was applied to analyze the influencing factors for the occurrence of PPCs after radical resection of esophageal cancer,and a decision tree prediction model for postoperative PPCs was constructed.Receiver operating characteristic(ROC) curve was used to analyze the value of related factors in predicting the occurrence of PPCs after radical resection of esophageal cancer.Results Univariate analysis showed that age,albumin/fibrinogen ratio,neutrophil/lymphocyte ratio,preoperative respiratory preparation,and drainage volume on the first day after surgery were associated with the occurrence of PPCs after radical resection of esophageal cancer(P<0.05).Multivariate logistic regression analysis indicated that age,albumin/fibrinogen ratio and drainage volume on the first day after surgery were independent influencing factors for the occurrence of PPCs after radical resection of esophageal cancer(P<0.05).The decision tree model identified drainage volume on the first day after surgery,albumin/fibrinogen ratio,age and neutrophil/lymphocyte ratio as predictive factors.The incidence rate of PPCs in the group without preoperative respiratory preparation was significantly higher than that in the group with preoperative respiratory preparation (62.5% vs. 37.5%,P<0.05).A drainage volume of 246.59ml on the first day after surgery was the optimal cutoff value for predicting the occurrence of PPCs after radical resection of esophageal cancer,and specificity was 93.04%,sensitivity was 87.5%,area under ROC curve(AUC) was 0.958,95%CI was 0.911-0.984.Moreover,the incidence rate of PPCs in patients with a drainage volume≤246.59ml on the first day after surgery was significantly higher than that in patients with a drainage volume >246.59ml (77.78% vs.3.60%,P<0.01).Conclusion Preoperative airway preparation and postoperative drainage volume are closely related to the occurrence of postoperative pulmonary complications (PPCs) after thoracoscopic radical surgery for esophageal cancer.Therefore,targeted measures should be taken for airway preparation before surgery,and changes in the patient's condition should be closely monitored after surgery to accurately determine the timing of drainage tube removal,which plays an important role in effectively preventing and treating PPCs.

Key words: esophageal cancer, pulmonary complications, thoracoscopic radical surgery, postoperative drainage volume, preoperative respiratory tract preparation