16 Open abdomen: analysis of indications, relation with peritonitis, outcomes and prognostic factors for mortality in non-traumatic patients

Abstract Aim The open abdomen (OA) is a surgical technique originally employed in critically traumatic patients, and later extended to other non-traumatic aetiologies, mostly peritonitis, vascular emergencies, or acute pancreatitis. Indications and results of OA in non-traumatic patients have not been rigorously described. The study aimed to analyse and report indications, prognostic factors of mortality, and the outcomes of OA in non-traumatic patients, with emphasis on peritonitis. Methods Single-center retrospective study of 94 OA patients from 2008 to 2021. The decision to perform OA relied either on the surgeon's judgment or mainly on the presence of at least one trauma OA criterion: hypotension (systolic blood pressure ≤70 mmHg), massive transfusion, coagulopathy (INR ≥ 1.7), acidosis (pH < 7.25), and hypothermia (<35°C). Statistical tests were performed to analyse survival and identify morbidity and mortality prognostic factors. Observed outcomes were compared to those predicted by preoperative using the Age-adjusted Charlson Comorbidity Index (ACCI) and postoperative using the Sequential Organ Failure Assessment score (SOFA score). Results OA was performed for peritonitis (n = 54), vascular emergencies (n = 23), pancreatitis (n = 11), abdominal compartmental syndrome (n = 2), and intestinal fistulas (n = 4). The overall 90-day mortality was 55.3% (n = 52), 55.5% (n = 29) were from the peritonitis group. The multivariate analysis emphasizes the major role of altered physiology in mortality. Although 71.05% of peritoneal fluid cultures were positive, being E. faecium (n = 13, 14.3%), P. aeruginosa (n = 12, 13.2%) the most common germs. mortality did not seem to be associated with positive peritoneal cultures or to a particular group of germs. Even though there were not statistically significant differences in the distribution of mortality peritonitis and acute pancreatitis may benefit most from the damage control and OA. approach. Conclusions OA can be a reliable treatment for critically ill patients with non-traumatic abdominal emergencies, especially in peritonitis and pancreatitis. Age, comorbidities, multi-organ failure and altered physiology are parameters whose effects seem to be associated with a worse survival rate. High mortality does not appear to be associated neither to positive peritoneal cultures nor to any particular group of germs.