A new checklist surgical hand scrub to replace time-based methods - A pixel intensity analysis

Hand scrubbing is an absolute precaution to avoid surgical site infections. World Health Organization (WHO) recommends 4-min overall scrubbing (4MS) for surgical hand hygiene. However, we hypothesize that the more methodical 10-stroke counting technique (10SS) via locational partitioning of the arm is superior to WHO's superficial guideline dictating only the duration.

The mechanical efficiency of 4MS and 10SS techniques are compared.

24 healthcare professionals were recruited for the study. A novel methodology was devised to quantify the average brightness change of skin-applied UV ink before and after scrubbing via pixel intensity analysis. A black-box setup is constructed with an integrated high-resolution camera to photograph the UV-stained dorsal arm. Each stain was then digitally isolated for brightness comparison.

It was observed that the 10SS technique was overall more successful in removing the UV ink in comparison to the 4MS method (p = 0.014). In addition, a bias was observed in removing more percentage of the proximal stains when compared to middle and distal stains with the 4MS technique (p = 0.0027), while location-based brightness change averages were statistically equal with the 10SS technique (p = 0.423).

10SS provided not only a more mechanically efficient scrubbing but also a more homogenous cleaning than 4MS. We recommend the use of the 10SS technique to achieve more effective pre-surgical hand hygiene.