OBJECTIVES: Bathing intensive care unit (ICU) patients with chlorhexidine gluconate prevents multiple types of hospital-acquired infections (HAIs). This secondary analysis evaluated the impact of chlorhexidine bathing on antimicrobial utilization in a surgical ICU using data from the chlorhexidine-bath (CHG-BATH) randomized trial.

METHODS: The primary outcome of this study was to compare total antimicrobial defined daily doses (DDDs) per patient-day between two study groups: chlorhexidine bathing every other day versus soap-and-water bathing daily. Systemically distributed antibiotics and antifungals were included in the analysis. Antivirals (except oseltamivir), antiparasitics, and prophylaxis antimicrobials were excluded. DDDs were calculated using the World Health Organization Anatomical Therapeutic Chemical/DDD 2018 Index. In the original CHG-BATH trial, HAIs were observed from 48 hours after randomization to 48 hours after the end of interventions, to account for latency period of HAIs. In this study, the observation period for antimicrobial utilization started 48 hours after randomization and ended 14 days after end of CHG-BATH trial follow-up, to account for completion of antimicrobial regimens, or hospital discharge, or death, whichever occurred first. The primary outcome was analyzed using unadjusted Mann-Whitney U Test. Two-sided p-value of 0.05 or lower indicated statistical significance.

RESULTS: Of 325 patients previously enrolled in the CHG-BATH trial, 312 (96%, 157 in soap-and-water, 155 in chlorhexidine) were included in this analysis. The median (inter quartile range [IQR]) of total DDDs per patient-days were 1.4(0.8-2.4) in soap-and-water and 1.4(0.5-2.2) in chlorhexidine (p=0.5). The median (IQR) of total DDDs per patient were 12.2(3.3-30.8) in soap-and-water and 12.0(3.1-24.9) in chlorhexidine (p=0.6).

CONCLUSIONS: Compared with daily soap and water bathing, 2% chlorhexidine bathing every other day was not associated with a decrease in antimicrobial utilization using the DDD per patient-day metric. Further analyses are needed to determine differences in total antimicrobial days, acquisition cost, and subgroups of antimicrobial classes and agents.