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.