Impact of Institutional Expected Practice Guidelines on Oral and Long-acting Intravenous Antibiotic Use for Serious Bacterial Infections

Abstract Background Expected practice interventions are a low resource antimicrobial stewardship strategy to standardize prescribing behavior by clinicians. An expected practice intervention to encourage use of oral and long-acting IV (PO/LAIV) antibiotics for serious infections was implemented at a U.S. tertiary care hospital in November of 2022. Methods We conducted a quasi-experimental pre/post study to evaluate the effect of guideline release on a primary outcome of length of stay (LOS) and secondary outcomes of inpatient antibiotic days, 3-month readmission, PO/LAIV antibiotic use, microbiologic failure, and adverse drug events. We also assessed key factors associated with use of PO/LAIV therapy receipt. Results Among 139 encounters, we found a significant increase in the proportion of encounters in which PO/LAIV therapy was prescribed after the intervention (42.0% vs 60.0%, p = 0.03). On multivariable analysis, LOS did not differ (adjusted rate ratio [aRR] 0.91; 95% CI, 0.74–1.13), nor did inpatient intravenous antibiotic days (aRR 0.95; 95% CI, 0.78–1.16). Post-implementation encounters had lower odds of 3-month all cause readmission (adjusted odds ratio [aOR] 0.37; 95% CI, 0.17–0.77) and higher odds of PO/LAIV use at discharge (aOR 2.77; 95% CI, 1.28–5.99). Conclusions Expected practice intervention implementation was associated with an increase in PO/LAIV therapy use and a reduction in readmission, supporting its role as a promising, low-resource antimicrobial stewardship strategy warranting further prospective evaluation.