Environmental contamination of a new general surgical ward

Hospital cleaning: past, present, and future

INTRODUCTION

The importance of hospital cleaning for controlling healthcare-associated infection (HAI) has taken years to acknowledge. This is mainly because the removal of dirt is inextricably entwined with gender and social status, along with lack of evidence and confusion over HAI definitions. Reducing so-called endogenous infection due to human carriage entails patient screening, decolonisation and/or prophylaxis, whereas adequate ventilation, plumbing and cleaning are needed to reduce exogenous infection. These infection types remain difficult to separate and quantitate. Patients themselves demonstrate wide-ranging vulnerability to infection, which further complicates attempted ranking of control interventions, including cleaning. There has been disproportionate attention towards endogenous infection with less interest in managing environmental reservoirs.

QUANTIFYING CLEANING AND CLEANLINESS

Finding evidence for cleaning is compromised by the fact that modelling HAI rates against arbitrary measurements of cleaning/cleanliness requires universal standards and these are not yet established. Furthermore, the distinction between cleaning (soil removal) and cleanliness (soil remaining) is usually overlooked. Tangible bench marking for both cleaning methods and all surface types within different units, with modification according to patient status, would be invaluable for domestic planning, monitoring and specification.

AIMS AND OBJECTIVES

This narrative review will focus on recent history and current status of cleaning in hospitals. While its importance is now generally accepted, cleaning practices still need attention in order to determine how, when and where to clean. Renewed interest in removal and monitoring of surface bioburden would help to embed risk-based practice in hospitals across the world.

Role of MRSA reservoirs in the acute care setting

Background  Nosocomial infection remains the most common complication of hospitalisation. Despite infection control efforts, nosocomial methicillin-resistant Staphylococcus aureus (MRSA) transmission continues to rise. The associated costs of increased hospital stay and patient mortality cause considerable burden to the health system. Objectives  This review sought to evaluate the role of reservoirs, particularly the environment and equipment commonly found in the clinical area, in the transmission of MRSA within the acute hospital. This review updates a review previously completed by the authors and published by the Joanna Briggs Institute (2002). Search strategy  A systematic search for relevant published or unpublished literature was undertaken using electronic databases, the reference lists of retrieved papers and the Internet. This extended the search published in the original review. Databases searched included  Medline (1966-August Week 1 2005), CINAHL (1982-August Week 1 2005), EMBASE (1996-Week 33), as well as the Cochrane Library (Issue 3, 2005) and the Joanna Briggs Institute Evidence Library (August 2005). Selection criteria  All research reports published between 1990 and August 2005 in the English language that focused on the role of the environment and equipment commonly found in the clinical area on the nosocomial MRSA transmission in adult, paediatric or neonatal acute care settings were considered. Data collection and analysis  Two reviewers assessed each paper against the inclusion criteria and a validated quality scale. Studies that scored less than the mean quality score were excluded from the review. Data extraction was undertaken using a tool designed specifically for this review. Statistical comparisons of findings were not possible, so findings are presented in a narrative form. Results  Forty-two papers met the review inclusion criteria, of which 18 obtained a quality score above the threshold and are included in this review. Seven studies reported general investigations of MRSA in the clinical environment and 11 studies explored specific environmental aspects. All studies used exploratory, descriptive or comparative designs. The evidence suggests that MRSA strains within the environment often match those found in patients within that environment. MRSA can be found in the air around MRSA colonised or infected patients. The degree of airborne contamination is significantly increased by activities that promote airflow. Although the site of MRSA colonisation or infection can influence the degree of environmental contamination, these data are inconsistent. Therefore, there is limited evidence for tailoring infection control interventions based on the sites of MRSA colonisation or infection. The evidence suggests that the type of materials used in clinical equipment can influence the effectiveness of cleaning techniques. Current routine cleaning practices, including conventional terminal cleaning, do not necessarily effectively eradicate MRSA from the environment. This review demonstrates that there is a link between the environment and hospital equipment and the transmission of MRSA within the acute hospital setting. Further well-designed research is urgently required to explore the efficacy of specific cleaning and decontamination methods, staff compliance with infection control practices and the range of factors that affect the incidence of MRSA contamination of the environment and equipment commonly found in the clinical area.

Role of MRSA reservoirs in the acute care setting

BACKGROUND

Nosocomial infection remains the most common complication of hospitalisation. Despite infection control efforts, nosocomial methicillin-resistant Staphylococcus aureus (MRSA) transmission continues to rise. The associated costs of increased hospital stay and patient mortality cause considerable burden to the health system.

OBJECTIVES

This review sought to evaluate the role of reservoirs, particularly the environment and equipment commonly found in the clinical area, in the transmission of MRSA within the acute hospital. This review updates a review previously completed by the authors and published by the Joanna Briggs Institute (2002).

SEARCH STRATEGY

A systematic search for relevant published or unpublished literature was undertaken using electronic databases, the reference lists of retrieved papers and the Internet. This extended the search published in the original review.Databases searched included Medline (1966-August Week 1 2005), CINAHL (1982-August Week 1 2005), EMBASE (1996-Week 33), as well as the Cochrane Library (Issue 3, 2005) and the Joanna Briggs Institute Evidence Library (August 2005).

SELECTION CRITERIA

All research reports published between 1990 and August 2005 in the English language that focused on the role of the environment and equipment commonly found in the clinical area on the nosocomial MRSA transmission in adult, paediatric or neonatal acute care settings were considered.

DATA COLLECTION AND ANALYSIS

Two reviewers assessed each paper against the inclusion criteria and a validated quality scale. Studies that scored less than the mean quality score were excluded from the review. Data extraction was undertaken using a tool designed specifically for this review. Statistical comparisons of findings were not possible, so findings are presented in a narrative form.

RESULTS

Forty-two papers met the review inclusion criteria, of which 18 obtained a quality score above the threshold and are included in this review. Seven studies reported general investigations of MRSA in the clinical environment and 11 studies explored specific environmental aspects. All studies used exploratory, descriptive or comparative designs. The evidence suggests that MRSA strains within the environment often match those found in patients within that environment. MRSA can be found in the air around MRSA colonised or infected patients. The degree of airborne contamination is significantly increased by activities that promote airflow. Although the site of MRSA colonisation or infection can influence the degree of environmental contamination, these data are inconsistent. Therefore, there is limited evidence for tailoring infection control interventions based on the sites of MRSA colonisation or infection. The evidence suggests that the type of materials used in clinical equipment can influence the effectiveness of cleaning techniques. Current routine cleaning practices, including conventional terminal cleaning, do not necessarily effectively eradicate MRSA from the environment. This review demonstrates that there is a link between the environment and hospital equipment and the transmission of MRSA within the acute hospital setting. Further well-designed research is urgently required to explore the efficacy of specific cleaning and decontamination methods, staff compliance with infection control practices and the range of factors that affect the incidence of MRSA contamination of the environment and equipment commonly found in the clinical area.

Rapid recontamination with MRSA of the environment of an intensive care unit after decontamination with hydrogen peroxide vapour

Meticillin-resistant Staphylococcus aureus (MRSA) persists in the hospital environment and conventional cleaning procedures do not necessarily eliminate contamination. A prospective study was conducted on an intensive care unit to establish the level of environmental contamination with MRSA, assess the effectiveness of hydrogen peroxide vapour (HPV) decontamination and determine the rate of environmental recontamination. MRSA was isolated from 11.2% of environmental sites in the three months preceding the use of HPV and epidemiological typing revealed that the types circulating within the environment were similar to those colonising patients. After patient discharge and terminal cleaning using conventional methods, MRSA was isolated from five sites (17.2%). After HPV decontamination but before the readmission of patients, MRSA was not isolated from the environment. Twenty-four hours after readmitting patients, including two colonized with MRSA, the organism was isolated from five sites. The strains were indistinguishable from a strain with which a patient was colonized but were not all confined to the immediate vicinity of the colonized patient. In the eight weeks after the use of HPV, the environment was sampled on a weekly basis and MRSA was isolated from 16.3% sites. Hydrogen peroxide vapour is effective in eliminating bacteria from the environment but the rapid rate of recontamination suggests that it is not an effective means of maintaining low levels of environmental contamination in an open-plan intensive care unit.

A purpose built MRSA cohort unit

The control of hospital-acquired infection, in particular methicillin-resistant Staphylococcus aureus (MRSA) remains a challenge. Our hospital has established a purpose built 11-bed cohort unit with on-site rehabilitation for care of patients colonized with MRSA, in an attempt to improve their quality of care. Prior to the opening of this unit a number of concerns were voiced and the aim of this study was to address these. First, to establish if patient cohorting reduces the likelihood of successful decolonization, second, to evaluate the risk of staff colonization, and finally to see if successful environmental control of MRSA is possible.A patient database was established detailing patient demographics, infection rates, eradication and reacquisition rates. Staff screening was performed weekly, at the start of a period of duty. Sixty environmental sites were screened before unit opening, at 48h, six weeks and at six months. There were 88 admissions in the first six months; 62 patients were colonized with MRSA, and 26 patients (10 surgical, 16 medical) had MRSA infections. Twenty-three of 88 patients (26%) were successfully decolonized, which compares favourably with an eradication rate of 20% for the rest of the hospital. Twenty staff members participated in weekly screening. Five staff members colonized with MRSA were detected and all were successfully decolonized. Environmental control was achieved with a combination of a daily detergent clean and a once weekly clean with phenolic disinfectant. Our preliminary data suggest that, despite cohorting patients colonized with MRSA, with proper education and supervised cleaning protocols, it is possible to control environmental MRSA load, successfully decolonize patients and limit the risk of staff colonization.

Mopping up hospital infection

Hospital cleaning is a neglected component of infection control. In the UK, financial constraints have forced managers to re-evaluate domestic services and general cleaning has been reduced to the bare minimum. Services have been contracted out in some hospitals, which has further lowered standards of hygiene. Control of infection personnel believe that cleaning is important in preventing hospital-acquired infections but they do not manage domestic budgets and have failed to stop their erosion. It is difficult to defend high levels of hygiene when there is little scientific evidence to support cleaning practices. This review examines the common micro-organisms associated with hospital-acquired infection and their ability to survive in the hospital environment. It also describes studies which suggest that comprehensive cleaning disrupts the chain of infection between these organisms and patients. It is likely that restoring hygienic standards in hospitals would be a cost-effective method of controlling hospital-acquired infection. Furthermore, good cleaning is achievable whereas the enforcement of hand washing and good antibiotic prescribing are not.