Impact of universal contact precautions and chlorhexidine bathing on the acquisition of carbapenem-resistant enterobacterales in the intensive care unit: a cohort study.

Abstract

Background: For the prevention of carbapenem-resistant Enterobacterales (CRE) acquisition in the intensive care unit (ICU), the effectiveness of universal contact precautions (UCP) and chlorhexidine gluconate (CHG) bathing is controversial.

Methods: With the aim of evaluating the effectiveness of UCP and CHG on CRE acquisition, this study was conducted in an ICU at a university-affiliated hospital in Seoul. Beginning in April 2017, all patients admitted to the ICU underwent weekly CRE screening and surveillance tests, and beginning in January 2018, UCP and CHG bathing were implemented for all patients. The pre-intervention period spanned from April to December 2017; the post-intervention period spanned from January 2018 to December 2019. The pre- and post-intervention CRE acquisition rates were subsequently compared using Kaplan-Meier analysis and log-rank tests, and independent risk factors for CRE acquisition were analysed using Cox proportional hazard modelling.

Results: Of 1,747 patients, 35 acquired CRE during their ICU stay. The CRE acquisition rate was 1.94 and 1.45 per 1,000 patient-days before and after the intervention, respectively, with no significant difference (p = 0.357). The incidence rate of multidrug-resistant organism (MDRO) colonisation decreased from 19.33 to 13.57 per 1,000 patient-days, with Poisson regression analysis showing a relative risk of 0.85 (95% confidence interval [CI] 0.738-0.945, p = 0.004). Additionally, multivariable Cox regression revealed that CRE acquisition was significantly associated with carbapenem exposure (adjusted hazard ratio [aHR] 2.555, 95% CI 1.208-5.405, p = 0.013) and the presence of more than four patients colonised with CRE during their ICU stay (aHR 2.639, 95% CI 1.157-5.243, p = 0.019). However, UCP and CHG bathing were not significantly associated with CRE acquisition (aHR 0.657, 95% CI 0.301-1.433; p = 0.291).

Conclusions: UCP and CHG bathing did not affect the CRE acquisition rate in the ICU of a low-prevalence area. A multimodal strategy including antibiotic stewardship is necessary for controlling the nosocomial spread of MDROs.