Relevance of pneumoperitoneum in the conservative approach to complicated acute diverticulitis. A retrospective study identifying risk factors associated with treatment failure.

BACKGROUND

The aim of this study is to evaluate the relevance of pneumoperitoneum on the success rate of non-operative management (NOM) of patients with complicated acute diverticulitis (AD), and the risk factors associated with failure.

METHODS

Observational retrospective cohort study of patients attended at the emergency department for AD from January 2015-August 2019. Patient demographics, blood tests, radiological data and initial treatment strategies were registered. NOM, based on intravenous antibiotics (ATB) and bowel rest, was defined as unsuccessful when emergency surgery (ES) and/or infection-related death took place. Patients initially treated with ES were excluded. Analysis was done with the IBM SPSS statistics 23.0.0.2 software.

RESULTS

According to modified Hinchey and WSES criteria, 99 (12%) of 826 AD episodes were complicated, with pneumoperitoneum on the CT scan in 89 (90.5%). NOM was undertaken in 93 (94%) cases, with a 91.5% success rate. Multivariate analysis revealed ASA class III-IV, and the presence of fluid collections >3 cm in diameter, but not distant free air, to be associated with NOM failure. However, the success rate of NOM was significantly higher in patients with pericolic pneumoperitoneum (98.5%) than in those with distant free air (80%) (P=0.02). Risk factors of NOM failure were an advanced age, high CRP and WBC values, and the presence of free fluid in >2 abdominal quadrants.

CONCLUSIONS

NOM in hemodynamically stable patients with complicated AD is a safe and feasible approach, even in the context of distant free air. Nevertheless, patients with isolated pericolic air did better in our series.