Background From October 2015, an Antimicrobial Stewardship Programme (ASP) was implemented in an internal medicine department by a multidisciplinary team. One of the interventions developed within this ASP was to promote the early switch of intravenous antimicrobial therapy to oral therapy through the introduction of Early Oral Switch Therapy (EOST) recommendations.

Purpose We aimed to assess the impact on consumption, cost and duration of intravenous antimicrobials of the introduction of EOST recommendations by clinical pharmacists as a part of an ASP.

Material and methods The study was prospective with a before–after design, divided into a pre-intervention phase (January–May 2015) and a post-intervention phase (January–May 2016). The intervention consisted of writing the advice of the EOST by the clinical pharmacist on the patient’s clinical chart. Target patients were those admitted to hospital internal medicine floors. They had all received more than 72 hours of selected intravenous antimicrobial treatment (co-amoxiclav, ceftriaxone, levofloxacin) and had clinical and analytical stability.

Variables compared between the study phases were: consumption of selected and general antimicrobials calculated by defined daily dose per 100 stays (DDD/100 stays); cost of selected and general antimicrobial treatment, calculated by total spending per 100 stays; duration of selected and general antimicrobial treatments, calculated by total days of antimicrobial treatment per patient. All statistical analysis were performed using SPSS v.19.0, with a significance level of p<0.05.

Results During the pre-intervention phase, mean consumption of IV antimicrobials was 6.3 DDD/100 stays (4.7–7.9), and during the post-intervention phase it was 6.1 DDD/100 stays (4.3–7.9) (p=0.07). The associated mean costs were of €8.9/100 stays versus €8.1/100 stays (p=0.90). In terms of duration, the length of intravenous antimicrobial treatment during the pre-intervention phase was 4.3 days/patient (4.2–4.5), and during the post-intervention phase it was 3.5 days/patient (3.4–3.7) (p=0.05).

Conclusion This study suggests successful implementation of an EOST. Differences were not statistically significant, but we found a trend towards decreasing intravenous antimicrobial duration, consumption and cost. ASP carried out by a multidisciplinary teams may result in a decrease in the overuse of intravenous antimicrobial treatments.

References and/or acknowledgements Martínez Vazquez, MJ. Estrategia de conversion de la vía intravenosa a la vía oral. Vigo: Ediciones Mayo 2002.

No conflict of interest