Risk factors for therapeutic failure in the management of post-operative peritonitis: a post hoc analysis of the DURAPOP trial

BACKGROUND: Therapeutic failure is a frequent issue in the management of post-operative peritonitis. OBJECTIVES: A post hoc analysis of the prospective, multicentre DURAPOP trial analysed the risk factors for failures in post-operative peritonitis following adequate source control and empirical antibiotic therapy in critically ill patients. PATIENTS AND METHODS: Overall failures assessed post-operatively between Day 8 and Day 45 were defined as a composite of death and/or surgical and/or microbiological failures. Risk factors for failures were assessed using logistic regression analyses. RESULTS: Among the 236 analysed patients, overall failures were reported in 141 (59.7%) patients, including 30 (12.7%) deaths, 81 (34.3%) surgical and 95 (40.2%) microbiological failures. In the multivariate analysis, the risk factors associated with overall failures were documented piperacillin/tazobactam therapy [adjusted OR (aOR) 2.10; 95% CI 1.17–3.75] and renal replacement therapy on the day of reoperation (aOR 2.96; 95% CI 1.05–8.34). The risk factors for death were age (aOR 1.08 per year; 95% CI 1.03–1.12), renal replacement therapy on reoperation (aOR 3.95; 95% CI 1.36–11.49) and diabetes (OR 6.95; 95% CI 1.34–36.03). The risk factors associated with surgical failure were documented piperacillin/tazobactam therapy (aOR 1.99; 95% CI 1.13–3.51), peritoneal cultures containing Klebsiella spp. (aOR 2.45; 95% CI 1.02–5.88) and pancreatic source of infection (aOR 2.91; 95% CI 1.21–7.01). No specific risk factors were identified for microbiological failure. CONCLUSIONS: Our data suggest a predominant role of comorbidities, the severity of post-operative peritonitis and possibly of documented piperacillin/tazobactam treatment on the occurrence of therapeutic failures, regardless of their type.