63 Transfer of Multidrug-Resistant Organisms to Healthcare Workers' Gloves and Gowns After Patient Contact Increases with Environmental Contamination

Friday, March 19, 2010: 11:45 AM
International South (Hyatt Regency Atlanta)
Elizabeth T. Rogawski , University of Maryland School of Medicine, Baltimore, MD
Anthony Harris, MD, MPH , University of Maryland School of Medicine, Baltimore, MD
J. Kristie Johnson, PhD , University of Maryland School of Medicine, Baltimore, MD
Kerri Thom, MD, MS , University of Maryland School of Medicine, Baltimore, MD
Eli Perencevich, MD , University of Iowa, Carver College of Medicine and the Iowa City VA Medical Center, Iowa City, IA
Mary S. Lee, BS , University of Maryland School of Medicine, Baltimore, MD
Daniel J. Morgan, MD , University of Maryland School of Medicine, Baltimore, MD

Background: Mechanisms of multidrug-resistant (MDR) bacteria transmission in the hospital are not well understood.  Healthcare worker (HCW) contact with the patient and environment are both thought to contribute to transmission.


Objective:   We determined the frequency, risk factors, and role of environmental contamination on contamination of HCW protective clothing with MDR A. baumannii, vancomycin-resistant Enterococcus (VRE), methicillin-resistant S. aureus (MRSA), imipenem-resistant (IR) P. aeruginosa, and carbapenem-resistant K. pneumoniae (CRKP).

Methods:  Interactions between HCWs and patients on Contact Precautions were observed in 6 intensive care units at the University of Maryland Medical Center, an urban tertiary care academic hospital.  Swabs were cultured from HCWs' hands prior to patient room entry and from gloves, gowns, and hands immediately after exit, before hand washing.  Nine environmental points in the patients' rooms were also swabbed for culture (sink, bed rail, bedside table, vital sign monitor, supply cart, door handle, IV pump, ventilator and floor).


Results:   Excluding 19 (2.8%) observations in which HCWs' hands were contaminated prior to room entry, 136 of 652 (20.9%) interactions resulted in contamination with colonizing MDR bacteria to the HCWs' gloves, gown, and/or hands.  MDR A. baumannii contamination occurred most frequently, 56 of 176 observations (33.5%, 95% confidence intervals (CI) 26.3, 40.7%), followed by IR P. aeruginosa, 16 of 89(18.6%, 95% CI 10.4, 26.8%) observations, MRSA, 25 of 157 (16.4%, 95% CI 10.5, 22.3%) observations,  CRKP, 11 of 68 (16.4%, 95% CI 7.5, 25.5%) observations and VRE, 27 of 181 (15.0%, 95% CI 9.8, 20.2%) observations.  73.5% of rooms had positive environmental cultures for an MDR organism known to be colonizing the patient.  Multivariate regression showed the following variables were associated with contamination with MDR bacteria: positive environmental MDR cultures (odds ratio (OR) 4.9, 95% CI, 3.2-7.5), respiratory therapists compared to nurses (OR 2.7, 95% CI 1.5-5.0), performing physical exam (OR 2.2, 95% CI 1.4-3.5), contact with endotracheal tube (OR 1.7, 95% CI 1.1-2.8) and duration in room >5 minutes (OR 1.7, 95% CI 1.1-2.6).

Conclusions:   The contamination of HCW protective clothing during routine care of patients with MDR organisms is more frequent with A. baumannii than other MDR bacteria. Patients' rooms were commonly contaminated and proved to be the best predictor of transmission to protective equipment.  Our results suggest that Contact Precautions and more aggressive environmental cleaning may decrease transmission.