Association between Intraoperative Blood Loss and Postoperative Outcomes in Colorectal Perforation: A Retrospective Observational Study in Japan

To investigate the association between intraoperative blood loss and postoperative major complications in patients undergoing emergency surgery for colorectal perforation.

This single-center retrospective observational study included 138 patients who underwent emergency surgery for colorectal perforation. Patients were classified into two groups based on intraoperative blood loss: ≥200 mL and <200 mL. The primary outcome was major complications defined as Clavien-Dindo grade ≥3 (including in-hospital death). Multivariable logistic regression analysis was performed to identify independent risk factors. Restricted cubic spline analysis was used to assess the dose-response relationship.

Major complications occurred in 45 patients (32.6%). Patients with blood loss ≥200 mL had a significantly higher rate of major complications compared with those with blood loss <200 mL (51.5% vs. 15.3%; p < 0.001). Multivariable analysis identified intraoperative blood loss ≥200 mL (adjusted odds ratio [OR], 4.21; 95% confidence interval [CI], 1.75-10.75; p = 0.002) and preoperative hypotension requiring vasopressor use (adjusted OR, 6.70; 95% CI, 2.47-20.01; p < 0.001) as independent risk factors. Restricted cubic spline analysis confirmed a dose-dependent relationship.

Intraoperative blood loss ≥200 mL was independently associated with major complications in emergency colorectal perforation surgery. Whether reducing intraoperative blood loss improves postoperative outcomes warrants further investigation.