[Analysis of risk factors of diaphragmatic hernia after thoraco-laparoscopic minimally invasive McKeown esophagectomy].

<b>Objective:</b> To explore the related risk factors of diaphragmatic hernia after thoraco-laparoscopic minimally invasive Mckeown esophagectomy (MIME). <b>Methods:</b> This is a retrospective controlled study. A retrospective analysis was conducted on the clinical data of patients who underwent MIME at the Department of Thoracic Surgery, Fourth Hospital of Hebei Medical University, from January 2016 to December 2023. A total of 619 patients were included. There were 423 males and 196 females, aged (63.7±7.6) years (range: 37 to 87 years). The diagnosis of diaphragmatic hernia after MIME was made based on clinical symptoms and CT scans. Patients were divided into two groups: the diaphragmatic hernia group (<i>n</i>=16) and the non-diaphragmatic hernia group (<i>n</i>=603). Clinical data, including age, gender, body mass index (BMI), smoking history, tumor location (upper, middle, and lower thoracic esophagus), preoperative neoadjuvant therapy history, and tumor staging, were collected and analyzed. A BMI of 25 kg/m² and age of 65 years were used as cutoff values. The <i>χ</i>² test and Fisher's exact test were used to compare the data between the two groups, and Logistic regression was employed for risk factor analysis. The diaphragmatic hernia group and non-diaphragmatic hernia group were matched in a 1∶3 ratio with a caliper value of 0.02 by propensity score matching. Kaplan-Meier method was used for survival analysis and compared using the log-rank test for between-group differences. <b>Results:</b> The proportion of patients with diaphragmatic hernia after MIME who underwent surgical treatment was 6/16. Statistically significant differences were observed between the diaphragmatic hernia group and the non-diaphragmatic hernia group in terms of age (<i>χ</i>²=16.057, <i>P</i><0.01), BMI (<i>χ</i>²=16.057, <i>P</i><0.01), and tumor location (<i>χ</i>²=12.048, <i>P</i>=0.002). Multivariate logistic regression analysis revealed that age ≥65 years (<i>OR</i>=1.236, <i>P</i>=0.023) and BMI<25 kg/m² (<i>OR</i>=0.810, <i>P</i><0.01) were independent risk factors for the development of diaphragmatic hernia after MIME. Survival analysis showed no significant difference in long-term survival between patients with and without diaphragmatic hernia after MIME (<i>P</i>=0.187), and whether patients with diaphragmatic hernia underwent surgery was not associated with long-term prognosis (<i>P</i>=0.560). <b>Conclusion:</b> Patients with BMI<25 kg/m² and age ≥65 years are independent risk factors for diaphragmatic hernia after MIME. The occurrence of diaphragmatic hernia is not associated with prognosis, and whether patients with diaphragmatic hernia undergo surgery does not affect the prognosis.