Implementation of an antimicrobial stewardship program in the Vascular Surgery ward of a university tertiary care hospital in Pavia, Northern Italy.

Purpose: The commitment of multidisciplinary teams in antimicrobial stewardship programs (ASPs) is often inadequately considered, especially in surgical wards. We wanted to evaluate clinical, microbiological, and pharmacological outcomes before and after the implementation of an ASP in the Vascular Surgery ward of Fondazione IRCCS Policlinico San Matteo, a tertiary care hospital in Pavia, Italy.

Methods: This was a quasi-experimental quality-improvement study. The antimicrobial stewardship activity was conducted twice a week for 12 months and consisted of both prospective audit and feedback of all the ongoing antimicrobial prescriptions by the infectious diseases' consultants and educational meetings for the healthcare workers of the Vascular Surgery ward. For comparison between the study periods, Student t test (Mann-Whitney test for skewed distributions) was used for quantitative variables (ANOVA or Kruskall-Wallis for > 2 groups respectively), and Pearson's chi-squared test (Fisher exact test where appropriate) for categorical variables. 2-tailed tests were used. P-value significance cut-off was 0.05.

Results: During the 12-month intervention period, among a total number of 698 patients, 186 prescriptions were revised, mostly leading to de-escalating an ongoing antimicrobial therapy (39, 20.97%). A statistically significant reduction in isolates of carbapenem-resistant Pseudomonas aeruginosa (p-value 0.003) and the absence of Clostridioides difficile infections were reported. No statistically significant changes were observed in terms of length of stay and all-cause in-hospital mortality. A significant decrease in the administration of carbapenems (p-value 0.01), daptomycin (p-value < 0.01) and linezolid (p-value 0.43) was registered. A significant reduction in antimicrobial costs was also observed.

Conclusions: The implementation of a 12-month ASP brought significant clinical and economic results, highlighting the benefits of a multidisciplinary teamwork.