High-pressure CO2 insufflation is a risk factor for postoperative ileus in patients undergoing TaTME.

The aim of this study is to evaluate the influence of high-pressure CO2 insufflation during TaTME on the occurrence of postoperative ileus. All patients undergoing elective transanal total mesorectal excision (TaTME) between April 2015 and March 2019 were included in a prospective database. Eligible patients were adults with mid and low-level rectal cancer undergoing elective TaTME with colorectal anastomosis and diverting ileostomy, following a standardized ERAS pathway. Patients were divided into a low-pressure (LP) group, where surgery was performed with an intrabdominal CO2 pressure of 12 mmHg, and a high-pressure (HP) group, where the intrabdominal pressure reached 15 mmHg of CO2 once the two surgical fields were connected. Of 98 patients undergoing TaTME in the observed period, 74 met the inclusion criteria and were included in this study. There was no significant difference in postoperative complications between the LP and HP groups, except for postoperative ileus, which occurred in seven patients (13.2%) in the LP group and seven patients (33.3%) in the HP group (p value 0.046). The logistic multivariate analysis showed that a high intraabdominal CO2 pressure (OR 7040, 95% CI 1591-31,164, p value 0.01) and male sex (OR 10,343, 95% CI 1078-99,256, p value 0.043) were significantly associated with postoperative ileus after TaTME. Intraabdominal CO2 pressure should be carefully set, as it may represent a risk factor for postoperative ileus in patients undergoing TaTME.