Background: Although previous studies have evaluated whether use of irrigation decreases postoperative intraabdominal abscess (PO-IAA) formation, these studies treated irrigation as a dichotomous variable and concluded that no irrigation resulted in a decreased incidence of PO-IAA formation. However, a recent study found decreased incidence with small aliquots to a total volume of 6 L. We hypothesized that higher volumes of irrigation would result in a lower incidence of PO-IAA. Materials and Methods: A postoperative template was developed as a quality improvement initiative and included descriptors for complex appendicitis and volume of irrigation. Data were prospectively collected from February 2016 to December 2018. Patients with complex appendicitis (fibropurulent exudate, extraluminal fecalith, well-formed abscess, visible hole in the appendix) were identified and analyzed by using standard statistical analysis. Volume of irrigation was categorized for analysis. Results: Two thousand three hundred six appendicitis patients were identified; 408 had complex appendicitis (17.7%). Three hundred eighty-four patients with complex appendicitis had documented irrigation volumes. The overall incidence of PO-IAA was 13.8%. Irrigation was commonly used (92.7%). The median amount of irrigation was 1000 mL (500 mL, 2500 mL), but it ranged from none to 9000 mL. There was no overall difference in the volume of irrigation used between those who developed a PO-IAA and those who did not (P = .34). No specific intraoperative finding was associated with the development of PO-IAA. Increasing volume of irrigation did not lower PO-IAA incidence (P = .24). Conclusions: The volume of irrigation did not appear to affect the rate of PO-IAA formation. The use of irrigation should be left to the discretion of the operating surgeon.
Keywords: appendicitis; complex; intraabdominal abscess; irrigation; perforated; ruptured.