Long-Term Survival in Generalized Peritonitis: The Impact of Early Critical Periods in Major Emergency Abdominal Surgery

Background: Generalized peritonitis is a severe intraabdominal infection associated with high morbidity and mortality in patients undergoing major emergency abdominal surgery. While short-term outcomes are well-documented, long-term survival and prognostic factors remain less explored. This study investigates four-year survival and conditional short-term survival to assess the impact of generalized peritonitis on long-term outcomes. Methods: This was a retrospective study from prospectively collected data from 2017-2020 of patients with age ≥ 18 undergoing major emergency abdominal surgery. All patients were treated within a high-quality, multidisciplinary standardized protocol. The primary outcome was four-year overall survival stratified according to degree of peritonitis. Secondary outcomes were conditional survival where the time at risk begins at postoperative day 30 and 90. The association between survival and risk factors were assessed with cox regression analyses. Results: A total of 966 patients were included, in which 21% (203/966) were found to have generalized peritonitis during surgery. Four-year overall survival rate for non-generalized peritonitis patients was 66% (95% CI: 62.38 – 69.12%) and for generalized peritonitis it was 53% (95% CI: 46.52 – 60.39%) with a log-rank test showing a significant survival difference (P = 0.00014). When assumed alive 30 days postoperatively, patients with generalized peritonitis still showed a significant survival difference (Log-rank test, P = 0.028), however interestingly, the impact of generalized peritonitis diminished when surviving 90 days past surgery (Log-rank test, P = 0.51). The hazard ratio for generalized peritonitis showed an increased risk of death for both overall (HR 1.57, 95% CI: 1.22 – 2.01, P <0.001) and 30-days conditional survival (HR 1.53, 95% CI: 1.12 – 2.09, P = 0.008), but the effect was non-significant for 90-days conditional survival (HR 1.23, 95% CI: 0.85 – 1.77, P = 0.267), indicating that the impact of generalized peritonitis is most crucial in the early postoperative period. Furthermore, cox regression analyses identified age > 70, ASA ≥ 3, and intraabdominal malignancy to be significantly associated with poor survival regardless of adjusting for short-term mortality. Conclusion: Patients with generalized peritonitis had significantly lower four-year overall survival compared to those without. Among patients who survived 30 days the difference was still there but after 90 days postoperatively no significant association on between peritonitis and long-term mortality was observed.