Author: Wong, Hoi Wan
Title: Assessment of near patient environmental contamination levels and contamination of personal stethoscopes used for patients in isolation rooms : Staphylococcus aureus and methicillin-resistant Staphylococcus aureus (MRSA)
Degree: M.Sc.
Year: 2012
Subject: Staphylococcus aureus -- Prevention.
Stethoscopes.
Isolation (Hospital care)
Hong Kong Polytechnic University -- Dissertations
Nosocomial infections -- Prevention.
Hospitals -- Sanitation.
Department: Faculty of Health and Social Sciences
Pages: ix, 76 leaves : ill. ; 30 cm.
Language: English
Abstract: Background: Environmental surfaces and equipment such as stethoscopes in hospitals serve as a reservoir for pathogenic organisms and increase the potential of infection transmission. Visual assessment commonly used to assess the cleanliness of the hospital environment is not reliable and is subjective. Objective assessment method is more appropriate. Also, use of designated equipment is also important to prevent transmission of pathogens. Objectives: 1) To assess the effectiveness of routine environmental cleansing in single isolation rooms of an infectious disease ward. 2) To assess the compliance of doctors routinely using patient-designated stethoscopes. 3) To determine contamination of doctors' personal stethoscopes for doctors not using patient-designated stethoscopes. Methods: A prospective, longitudinal and descriptive study was conducted in an isolation ward in a Hong Kong hospital. Swabs of bed rails and over bed tables were taken before and after every morning cleaning after patients were admitted to the single isolation rooms. A maximum of 4 days swabs were taken for each patient. In addition, swabs were collected from designated stethoscopes before doctors' morning rounds. The designated stethoscope was sampled again after morning rounds if the doctor had used it. If doctors did not use the designated stethoscope and used their personal stethoscopes during morning round, swabs on personal stethoscopes were taken. All swabs were cultured for Staphylcoccus aureus (S. aureus) and methicillin-resistant Staphylococcus aureus (MRSA) using agar--chromo IDTM S. aureus (SAID) (Biomerieux) and chromIDTM MRSA (Biomerieux). The agar plates were spread and incubated for 18-24 hours at 37°C. The green colony on the agar representing S. aureus and MRSA was identified and categorized into six microbial growth categories (no growth, very scanty, scanty, few, many and numerous) after adjusting the size factors of the swabbing area.
Results: Both bed rails and over bed tables were more contaminated with S. aureus than with MRSA before and after cleaning of twenty five patients' rooms. Before cleaning, contamination levels of bed rails and over bed tables were not related. They were related after cleaning, but their association was weak (rs=0.265, p=0.022). Although over bed tables were more contaminated than bed rails before cleaning, they were more effectively cleaned than bed rails. 44% of isolation rooms were considered contaminated, but they were effectively cleaned (p<0.001, McNemar test). It was also noted that 98.7% of doctors did not use the designated stethoscopes. Conclusion: The results of this study indicate that cleaning of the near patient environment using disinfectant may not result in clean surfaces. The compliance of doctors using patient-designated stethoscopes was poor. And MRSA was found on designated stethoscopes and personal stethoscopes. It is essential to make sure the cleaning staffs clean the environment using appropriate methods. Also, it is important to encourage doctors and other healthcare workers (HCWs) to use the designated stethoscopes and strictly follow hand hygiene practice in order to prevent transmission of pathogens in hospitals.
Rights: All rights reserved
Access: restricted access

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