Risk Factors for Postoperative Mortality in Patients with Colorectal Diverticular Perforation.

Objectives: The prognosis of patients with colorectal diverticular perforations requiring surgery is poor, and the efficacy of polymyxin B-immobilized fiber column direct hemoperfusion (PMX-DHP) in these patients has not yet been established. In the present study, we evaluated the prognostic factors and the efficacy of PMX-DHP in surgically treated patients with perforated colorectal diverticula. Methods: Of the 116 patients with colorectal perforations who underwent emergency surgery at our hospital between April 2018 and May 2023, we retrospectively reviewed 46 patients with perforated colorectal diverticula. Preoperative, surgical, and postoperative factors were compared between the survival and mortality groups. Subgroup analysis was performed to evaluate the efficacy of PMX-DHP in severe cases. Results: The postoperative mortality group included 7 patients (15.2%), and PMX-DHP was performed in 14 (30.4%). PMX-DHP was performed significantly more often in the mortality group (P<0.01). In multivariate analysis, antithrombotic drug administration (hazard ratio, 16.600; 95% confidence interval, 1.32-209; P<0.05) and higher lactate levels (≥ 3.0 mmol/L) (hazard ratio, 42.300; 95% confidence interval, 2.69-667, P<0.01) were independent risk factors for postoperative mortality. PMX-DHP was performed in severe cases (patients with higher lactate levels, APACHE II scores, ventilator management frequencies, and noradrenalin use). PMX-DHP was not effective in improving prognosis in severe cases. Conclusions: Administration of antithrombotic drugs and higher lactate levels (≥ 3.0 mmol/L) are independent prognostic factors in colorectal diverticular perforations. PMX-DHP may not be effective in patients with severe preoperative conditions.