Impact of an Automatic Stop Order for Meropenem Use in Patients with Sepsis at the Inpatient Department of Warin Chamrap Hospital

Abstract

Background: Prolonged and inappropriate meropenem use can contribute to antimicrobial resistance and increase healthcare costs. Warin Chamrap Hospital implemented an automatic stop order (ASO) requiring infectious diseases physician approval for continuation of meropenem treatment.

Objective: To compare meropenem consumption, duration of therapy, clinical outcomes, length of stay, and costs before and after ASO implementation.

Methods: A quasi-experimental pre-post study included patients aged ≥18 years with sepsis who received meropenem for ≥24 hours. A total of 300 patients were equally divided into pre-implementation (November 2023–December 2024) and post-implementation (January 2025–February 2026) groups. Data were retrieved from electronic health records. Continuous and categorical data were compared using the Pearson chi-square, Fisher’s exact, and Mann–Whitney U tests, as appropriate. Associations between study period and clinical outcomes were assessed using separate multivariable Firth penalized logistic regression models. Adjusted odds ratios (aORs) and 95% profile likelihood confidence intervals (CIs) were reported, with the pre-ASO period as the reference. Statistical significance was set at p-value < 0.05.

Results: Following ASO implementation, cumulative meropenem consumption per patient decreased from 14.00 to 12.00 g (p-value = 0.035). Median DDDs per 1,000 patient-days decreased from 444.44 to 333.33 (p-value = 0.006), and DOT per 1,000 patient-days decreased from 600.00 to 535.90 (p-value = 0.019). After adjustment, no significant between-group differences were observed in clinical improvement, clinical worsening, mortality, or treatment refusal. However, the adjusted odds of patient transfer were lower in the post-implementation group (aOR 0.28; 95% CI: 0.12–0.62, p-value = 0.001). Length of stay did not differ significantly (10 vs 11 days; p-value = 0.270), while total meropenem expenditure decreased by 86,530 Thai baht.

Conclusions: ASO implementation was associated with reduced meropenem utilization and expenditure without evidence of increased adverse clinical outcomes. Although patient transfer was less likely after adjustment for age, sex, ward type, underlying diseases, and infection sites, disease severity and unmeasured confounders were not accounted for. Therefore, these findings indicate an association rather than a causal relationship.