Abstract
Introduction
Deep prosthetic joint infection is a major cause of morbidity. Previous work has shown that infected skin scales shed by members of staff in the operating theatre are the key source of infection. Much attention has been given to the design of ultra clean operating theatres but remarkably little attention has been given to factors controlling skin scale shedding.
The aim of this study was to develop a novel method of direct visualisation and quantification of skin scales and to assess the effect of a simple skin care regimen on skin scales.
Patients/Materials & Methods
Direct visualisation of the skin surface at high power is difficult due to the depth of surface contours in relation to microscope depth of field. A Zeiss stereo compound Axio-Zoom microscope was used containing a stage on which subjects’ upper or lower limbs could be comfortably placed. A reflected light source allowed direct visualisation of a magnified image of the skin surface. Real-time digital manipulation of multiple z-stacked images on a linked computer created a composite three dimensional image of the skin surface. Density of skin scales was then calculated from this image.
We tested the effect of a standardised skincare regime consisting of washing, exfoliation and moisturisation on skin scale density at multiple sites and contralateral controls.
Results
The z-stack images provided excellent visualisation of the skin. There was considerable variation in skin scale density between individuals. Our data demonstrated a reduction in skin scale density at a study site during each successive stage of the skin care regimen. This effect was sustained even when the regimen was performed 12 hours prior to image acquisition. There was a marked reduction in skin scale density in treated compared to untreated contralateral sites, which was maintained over a period of hours.
Discussion
This study demonstrates a practical reproducible method of direct visualisation of the skin and quantification of skin scales. The method is suitable for a larger scale study of orthopaedic theatre staff during a working day and to measure the effect of the simple skin care regimen in this population. We have also conducted a pilot study in a clean room and we use surface microscopy to help study the relationship between skincare, clothing and contamination measured in CFU/cubic meter of air.
Conclusion
It is hypothesised that a daily skin care regimen comprising washing, exfoliating and moisturising for operating theatre staff would be expected to reduce intraoperative skin scale shedding and consequently prosthetic joint infection rates. Regular exfoliation by surgical staff is likely to substantially reduce airborne contamination in clean air theatres.
