Antibiotic management programme in a tertiary intensive care unit: effects of a carbapenem-restricted period on clinical and laboratory parameters and costs of infections

Background: Carbapenems are antibiotics used for serious infections. The consumption of carbapenems has increased worldwide due to increasing microbial resistance. Aim: To investigate the effects of a carbapenem-restricted antimicrobial stewardship programme (ASP) on changes in the resistance profiles of infectious agents, the amount of antibiotics used, length of stay in the intensive care unit (ICU), mortality, and costs. Methods: Patients hospitalized in ICU between July 1st, 2020 and May 1st, 2021 were divided into two periods: the carbapenem-non-restricted period (CNRP); and the carbapenem-restricted period (CRP) in which alternative antibiotics to carbapenems were preferred during infection. The defined daily dose (DDD) per 100 patient-day methodology was used to calculate the antibiotic consumption. Findings: Of the 572 patients included in the study, 62.2% were male, and mean age was 70.5 years. In the blood culture the most frequently Gram-negative agent was Acinetobacter baumannii (25%). A. baumannii bloodstream infections with multidrug-resistant and extensively drug resistant micro-organisms were significantly different between the two periods (CNRP: 95.6% (N = 22), CRP: 66.6% (N = 8); P = 0.04). There was a gradual decrease in the incidence density and rate of nosocomial infection (P = 0.06), and a significant decrease in meropenem consumption between the two periods (CNRP vs CRP: 21.19 vs 6.37 DDD per 100 patient-days respectively; P = 0.007). ASP yielded US$8,600 of antibiotic cost savings and a total of 14% patient cost savings (P < 0.05) per patient. Conclusion: Combining an effective ASP with a comprehensive infection control programme may mitigate the emergence of antimicrobial-resistant bacteria. (c) 2024 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.