Does use of intraoperative irrigation with open or laparoscopic appendectomy reduce post-operative intra-abdominal abscess?

To date, no study shows a decrease in postoperative abscess with the use of irrigation during appendectomy. Postoperative abscess rate for laparoscopic and open appendectomy is 3.3 and 2.6 per cent. The purpose of this study is to determine if irrigation at appendectomy decreases the postoperative intra-abdominal abscess rate. Retrospective chart review of 176 consecutive appendectomies, open (39%) and laparoscopic (61%), at a university affiliated tertiary care facility from July 2007 to November 2008 for use of intraoperative irrigation was performed. Patients under age 18 were excluded. There were no differences between the irrigation groups in regards to age, sex, or weight. Perforation was observed in 28 per cent (50/176), of which 86 per cent (43/50) of patients received intraoperative irrigation. Eleven patients (9.6%) with irrigation developed postoperative abscess compared with two (3.3%) patients without irrigation (P = 0.22). Our results do not show decrease in postoperative intra-abdominal abscess with use of intraoperative irrigation. Thirteen patients developed postoperative abscess: 11 with irrigation, two without irrigation. Ten of 13 patients who developed abscess were perforated; nine with irrigation and one without. These results suggest routine use of intraoperative irrigation for appendectomies does not prevent intra-abdominal abscess formation, adds extra costs, and may be avoided.