Improving antimicrobial treatment in terms of antimicrobial stewardship and health costs by an OPAT service.

PURPOSE: Outpatient parenteral antimicrobial therapy (OPAT) is a standard for antimicrobial therapy internationally. With this prospective cohort study, we aimed to assess the impact of an OPAT service as part of antimicrobial stewardship (AMS) and evaluate the safety and efficiency of the program while illuminating the financial benefit for the hospital. METHODS: Socio-demographic data, treatment regimen and outcomes were prospectively recorded for all patients assigned to the program of the OPAT unit of the University Hospital of Zurich between November 2018 and September 2022. RESULTS: In total, we recorded 303 OPAT assignments of which 260 resulted in effective OPAT episodes. The 260 OPAT episodes were further optimized toward the choice of antimicrobial agent (n = 18) and length of therapy (n = 6). Moreover, OPAT resulted in alteration of patient assessment and care led by AMS strategies in 247 of 260 episodes (95%). While the bed days saved per year increased consistently with time, a total of 3934 in-hospital treatment days were saved amounting to a cost saving of 9,835,000 CHF over 47 months. Adverse events were recorded in 46 cases whilst only two of these have been the reason for readmission during OPAT treatment. Clinical cure was noted in 77% (199/260) and was negatively associated with Charlson Comorbidity Index (CCI; OR per 1 unit higher 0.85 (95% CI 0.78-0.93)). CONCLUSION: This study demonstrates the impact of an OPAT service in the framework of AMS as well as its benefits for the hospital whilst preserving safety and efficacy for the patient's parenteral antimicrobial treatment.

Review of the first comprehensive outpatient parenteral antimicrobial therapy program in a tertiary care hospital in Japan.

OBJECTIVES: The infectious diseases team at Kameda Medical Center, Japan, implemented a new outpatient parenteral antimicrobial therapy (OPAT) program in July 2012 and expanded the program with the support of home care services. This study reviews the OPAT program after 5.5 years of operation. METHODS: We prospectively collected data about the age, sex, diagnoses, causative organisms, types of OPAT, modes of administration, selected antibiotics, treatment durations, bed days saved, outcomes, readmissions, and estimated cost reductions of all patients who were treated in the OPAT program from July 2012 to December 2017. RESULTS: Of the 66 patients treated under the OPAT program, 45 (68.2%) were treated using clinic OPAT, and 21 (31.8%) were treated using homecare OPAT. The most commonly targeted organism was methicillin-susceptible Staphylococcus aureus. Continuous infusion with elastomeric pumps was employed in 55 patients (83.3%). Cefazolin was the most frequently used antibiotic (39.4%), followed by penicillin G (24.2%). The median OPAT duration was 13 days (range, 3-51), and the total bed days saved was 923. The estimated medical cost reduction was approximately 87,000 US dollars. CONCLUSIONS: Our experience shows that OPAT is a safe and feasible practice not only for efficient bed utilization and medical cost savings but also for better antimicrobial stewardship.