Open Abdomen Versus Primary Closure in Non-Trauma Patients: A Weighted Analysis of a Single Center Experience

Abstract Introduction In the last few years the open abdomen (OA) gained popularity in emergency general surgery. Our aim was to compare OA vs definitive primary closure (DC) in patients who underwent surgery for abdominal emergencies in a single referral center. Methods Emergency laparotomies (EL) from 2017 and 2023 were reviewed and stratified in OA and DC. Differences were balanced by inverse probability weighting (IPW), and 90-day mortality estimated. Subgroup analysis was carried out for patients with Mannheim Peritonitis Index (MPI) > 26, bowel obstruction (BO), bowel ischaemia (BI) and gastro-intestinal tract perforation (GIP). Results Of 320 patients, 167 were DC and 153 OA. Groups were different for ASA, Comorbidities, transfusions rate (TR), P-Possum score (PP), MPI, clinical frailty score (CFS), diagnosis and resection. Two balanced pseudo-populations were created by IPW. The 90-days survival rate was 50.8% for DC and 60.8% for OA (HR 0.79CI:0.40–1.55 p:0.502). At the Cox regression, CFS (HR1.125,95%CI:1.01–1.25,p:0.033) and BI (HR5.531,95%CI:2.37–12.89, p < 0.001) were independent risk factors for mortality. TR (OR3.44,CI:1.44–8.23, p < 0.006) and length of stay in ICU (LOS_ICU) (OR1.13,CI:1.07–1.20,p < 0.001) were associated with major complications. OA did not modify mortality in case of BO, MPI > 26, and GIP. OA (HR0.056,95%CI:0.01–0.22,p = 0.001), and large bowel resection (HR6.442,95%CI:1.28–32.31,p = 0.040), were predictors of longer survival in the subgroup of patients with BI. Conclusions OA was not related to a higher complication rate or higher mortality, but it resulted in a longer hospital stay and it did not improve the rate of ostomy. Only in the BI group the superiority of OA was established.