Short Postoperative Intravenous Versus Oral Antibacterial Therapy in Complicated Acute Appendicitis

Objective: The purpose of this study is to investigate noninferiority of postoperative oral administration of antibiotics in complicated appendicitis. Background: Recent investigations have used exclusively intravenous administration of antibiotics when comparing outcomes of postoperative antibacterial therapy in complicated appendicitis. We hypothesized that oral antibacterial treatment results in noninferior outcomes in terms of postoperative infectious complications as intravenous treatment. Methods: In this pilot, open-label, prospective randomized trial, all consecutive adult patients with complicated appendicitis including gangrenous appendicitis, perforated appendicitis, and appendicitis with periappendicular abscess between November 2020 and January 2023 were randomly allocated to 24-hour intravenous administration of antibiotics versus 24-hour oral administration of antibiotics after appendectomy. Primary outcomes included 30-day postoperative complications per Comprehensive Complication Index (CCI). Secondary outcome was hospital length of stay (HLOS). Follow-up analysis at 30 days was conducted per intention to treat and per protocol. The study was registered at ClinicalTrials.gov (NCT04947748). Results: A total of 104 patients were enrolled with 51 and 53 cases allocated to the 24-hour intravenous and the 24-hour oral treatment group, respectively. Demographic profile and disease severity score for acute appendicitis (DSS) were similar between the study groups. There were no significant differences between the study groups in terms of 30-day postoperative complications. Median CCI did not differ between the study groups. HLOS was similar in both groups. Conclusions: In the current pilot randomized controlled trial, the 24-hour oral antibiotic administration resulted in noninferior outcomes when compared to 24-hour intravenous administration of antibiotics after laparoscopic appendectomy in complicated appendicitis.