PM1019: Reduction of Linezolid Use in the Pediatric Cardiovascular ICU Following Introduction of an Antibiotic Stewardship Program

Purpose/Objectives: During recent years, antibiotic resistance has become of increasing concern in the healthcare setting. To address this, antibiotic stewardship programs (ASPs) have been shown to effectively reduce antibiotic use while maintaining optimal patient outcomes. We introduced an ASP within the Cardiovascular Intensive Care Unit (CICU) of our institution. Linezolid was identified by our pharmacy department to be one particular broad-spectrum antibiotic of frequent use within the CICU. Thus, the objective of this intervention was twofold: to decrease the linezolid days of therapy per 1000 patient-days and to decrease inappropriate use of linezolid within the CICU according to the proposed guideline.

Design/Methods: We developed a guideline for appropriate use of linezolid in conjunction with the Infectious Disease department. Educational sessions were held with CICU attending physicians to introduce guidelines and highlight the aims of the project. Using data collected by the pharmacy department, we retrospectively reviewed all charts of patients admitted to the CICU who received linezolid between January 2020 and July 2021. During the intervention cycle, a pharmacist performed antibiotic time-outs during daily rounds. Intervention data was then collected and retrospectively reviewed from August 2021 to February 2022. Statistical analysis was performed using one tailed t-test and a two proportion z-test.

Results: Pre-intervention data (n=96) demonstrated a mean DOT/1000 patient-days of 49 ± 28. Post-intervention data (n=20) showed a mean DOT/1000 patient-days of 27 ±17. This represented a significant decrease in the average length of treatment (p < 0.05). We found a significant decrease in the percentage of inappropriate antibiotic use, as defined by our algorithm, from 79% to 55% (p < 0.01). When analyzing the reason for inappropriate administration, the overall most common reason was lack of contraindication to vancomycin (55%).

Conclusion/Discussion: ASPs have been shown to be an efficacious way to combat the growing problem of antibiotic overuse. We identified linezolid as a frequently used broad-spectrum antibiotic within our CICU and aimed to both decrease total and inappropriate use. When comparing our pre- and post-intervention data, we found a significant difference within both of these parameters. Although we did find statistical significance, we noted variability from month to month (as reflected by wide standard deviations of the mean) of DOT/1000-patient days, indicating a need for further data collection to follow the trend over time. This project is ongoing, and we will continue to have periodic educational sessions, with the final objective of bringing the use of Linezolid in our institution to national average. Given that our most common reason for inappropriate administration was lack of vancomycin contraindication, our next cycle will focus on these key points specifically to further decrease misuse and combat antimicrobial resistance while maintaining patient outcomes.