Methods for evaluating changes in skin condition due to the effects of antimicrobial hand cleansers: Two studies comparing a new waterless chlorhexidine gluconate/ethanol-emollient antiseptic preparation with a conventional water-applied product

Background: Hand-cleansing products that are milder to the skin of health care personnel are being developed. but the available methodologies to appropriately evaluate these products and quantify differences are not generally being applied in well-controlled studies. Methods: Two randomized, blinded, bilateral comparison studies evaluated skin condition during use of 2 antiseptic hand preparation products: a new 1% chlorhexidine gluconate (CHG)/61% wt/wt ethanol antiseptic hand preparation in a unique emollient system for waterless/brushless application and a conventional 4% CHG antimicrobial product that is applied with water and a scrub brush. Trained technicians applied treatments 6 times (for a surgical scrub study) or 24 times (for a personnel handwash study) daily to the hands of healthy volunteers during 5 days of controlled washing. An expert grader evaluated skin for dryness, erythema, and roughness. Subjects completed a self-assessment questionnaire on skin condition. Transepidermal water loss was measured by an evaporimeter, and the skin Surface hydration level was measured by an electrical conductance meter. Results: Fifty-eight subjects were enrolled in the 2 studies and received both treatments. In general, skin treated with the waterless CHG/ethanol product scored significantly (P < .004) better on evaluations of visual dryness and erythema and showed greater improvement in the level of hydration (P < .003). In the health care personnel handwash study, transepidermal water loss was less than that for skin treated with the conventional CHG product (P < .002). Subject assessments showed similar results (total score, P < .007). Conclusions: All 3 approaches of expert grader evaluation, subject assessment, and instrumentation were in concordance, demonstrating that the waterless CHG/ethanol product was gentler to skin than the conventional CHG product.