Safety and efficacy of short-course intravenous antibiotics after complicated appendicitis in selected patients.

BACKGROUND: After surgery for complicated appendicitis (CA), common practice is to treat all patients with a standardised long-course of intravenous antibiotics (IVAB) to reduce the risk of postoperative surgical infections (PSI). The aim of the current study was to evaluate the safety and efficacy of a short-course IVAB after CA in selected patients. METHODS: The Department's prospectively collected database identified CA patients treated between2015 and 2019. Baseline and treatment characteristics and postoperative outcomes were analysed. The cut-off between short- and long-course IVAB was 2 days. Outcomes of interest were PSI and 30-day unplanned readmission. RESULTS: In total, 226 patients had CA: Ninety-nine CA (43.8%) received short-course IVAB and 127 (56.2%) received long-course. PSI occurred in 6% and 10% of the short-course and long-course patients, respectively (p = 0.34). Length of IVAB after a PSI was comparable to that of patients without PSI (median 3 and 2 days of IVAB respectively; p = 0.28). 30-day unplanned readmission rates were 7% and 6%, respectively (p = 0.99). Length of IVAB for readmitted patients was similar to those who were not readmitted (median 3 days of IVAB in both; p = 0.91). Multivariable analysis showed that the intraoperative findings of the appendix (p = 0.04) was a prognostic predictor for PSI. ASA score (p = 0.02) and surgical approach (p = 0.05) were prognostic predictors for 30-day unplanned readmission. CONCLUSIONS: This study shows that when patients respond well, a short-course IVAB can safely be applied after CA without increasing risk of PSI or 30-day unplanned readmission.