Extent and predictors of microbial hand contamination in a tertiary care ophthalmic outpatient practice

by Lam, Fung

Abstract (Summary)
(Uncorrected OCR) Abstract of thesis entitled "Extent and Predictors of Microbial Hand Contamination in a Tertiary Care Ophthalmic Outpatient Practice" submitted by Lam Fung, Robert for the degree of Master of Public Health at The University of Hong Kong in August 2005 Objectives: Combining microbiological laboratory and epidemiological techniques, this study aims to 1) describe the hand cleansing practices among ophthalmologists, to identify factors associated with inadequate hand washing and to examine the relationship with potential risk behaviours and environmental factors; 2) quantify the extent of microbial hand contamination among ophthalmologists during routine clinic practice; 3) review relevant literature from other hospital settings and to provide recommendations on hand cleansing practices based on the microbiological and epidemiological evidence. Setting: Ophthalmic outpatient clinic, Hong Kong Eye Hospital, a tertiary teaching facility in Hong Kong. Methods: This was a single-masked cross-sectional study of hand flora of ophthalmologists before and after patient contact, and after hand washing by agar imprints of the dominant hand. All growths were identified, counted and classified as '* resident or transient flora according to pre-specified criteria. Standardised questionnaires were used to collect information concerning the hand cleansing practices, patient load, glove use, and self-reported factors for poor adherence to hand cleansing. All cultures were obtained without direct observation in order to minimise the Hawthorne's phenomenon. Stepwise multiple linear regression models were constructed to determine the most robust predictors for resident and transient floral load. Results: The mean number of patients seen per hand washing and hand cleansing episode were 14.2 ?14.1 (range 1 - 52) and 11.2 ?13.3 (range 1 - 52) respectively. Over 80% of ophthalmologists believed their hand washing practices were inadequate, with "too busy" and "poor tolerability of hand washing agents" perceived as the most important barriers. Of the 108 cultures, 107 (99.1%) were culture positive, yielding 15 separate organisms. Coagulase negative Staphylococcal species and gram negative bacilli were the commonest resident and transient flora respectively. Thirty-five (97.2%) and 8 ophthalmologists (22.2%) were culture positive for at least one resident and transient organism respectively before patient contact Regression models showed alcohol-based hand rub use, transient and resident floral load before patient contact, and patient load collectively explained 58.7% of the variance in resident floral load after patient contact Hand washing with chlorhexidine was a significant predictor for transient floral load after hand washing (un-standardized 0 = -17.2, 95% CI = -10.2 to -24.2, P< 0.01). Conclusions: Hand washing might not be the most practical method in the prevention of microbial hand contamination, and the emphasis should be shifted from traditional hand washing to hand anti-sepsis with alcohol-based hand rubs. More rapid access to hand decontamination offered by these rubs had the potential to improve adherence, while maintaining good in vivo activity and tolerability against microbial contamination. Actual hand washing, in contrast, should be performed with chlorhexidine gluconate, as it had been shown to significantly reduce the transient flora, with documented persistent activity. Future research should focus on 1) evaluation of the above recommendations in terms of improving hand cleansing adherence, microbial hand contamination, tolerability and the ultimate prevention of nosocomial infections; 2) the determinants of microbial hand contamination prior to patient contact; 3) dissecting out the barriers for hand cleansing adherence at individual levels. Word Count for abstract: 499
Bibliographical Information:


School:The University of Hong Kong

School Location:China - Hong Kong SAR

Source Type:Master's Thesis

Keywords:hand washing china hong kong ophthalmology practice


Date of Publication:01/01/2005

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