Using antimicrobial solution for irrigation in appendicitis to lower surgical site infection rates

Background: The use of antimicrobial solutions for irrigation in appendicitis is controversial. Numerous antiseptic and antibiotic solutions have been suggested for use as an intraoperative irrigant. We sought to determine whether there was a difference in postoperative surgical site infections (SSIs) comparing normal saline (.9%), antiseptic solution (Dakin's, .25%), and an antibiotic solution (imipenem 1 mg/mL). Methods: We performed a retrospective study of adult appendectomies from January 1997 through November 2007 at a single institution The data were evaluated by multivariate logistic regression analysis and chi-square test. The incidences of postoperative overall SSI, wound infection, and abdominal abscess were compared. Results: A total of 1,063 cases were identified. Saline (n = 661) had an SSI rate of 9.8% (65/661), a wound infection rate of 7.3% (48/661), and an abdominal abscess rate of 4.2% (28/661). Dakin's (n = 208) had an SSI rate of 20.7% (43/208), a wound infection rate of 15.9% (33/208), and an abdominal abscess rate of 9.1% (19/208). Imipenem (n = 194) irrigation had an SSI rate of .5% (1/194), a wound infection rate of .5% (1/194), and an abdominal abscess rate of .5% (1/194). Conclusions: These results suggest that abdominal irrigation with an antibiotic solution (imipenem 1 mg/mL) is superior to both normal saline and Dakin's solution.