Comparing the Sterility and Visibility of Surgical Marking Pens Available in Australia

Six volunteers will have both anterior thighs marked with 12 surgical marking pens. The pens will be marking pens sold from the following companies: Pentel (N50), Artline (90), Sharpie (Super), Covdien, DeRoyal, Viscot, Concord, Sandel, Matrix, Aspen, Medline and SMI. The lines will be 5cm in length in parallel. Each thigh will be washed with one of four alcohol-based surgical preparation liquids. Each wash will be performed using sterile gauze swabs and forceps in a simulated operation setting. A first coat will be allowed to dry, followed by a second coat. The volume of liquid will be approximately 150mL. The liquids will be brown tinted 1% Iodine (w/v) with 70% isopropyl alcohol (v/v), pink tinted 0.5% chlorhexidine gluconate (w/v) with 70% isopropyl alcohol (v/v), red tinted 2% chlorhexidine gluconate (w/v) with 70% isopropyl alcohol (v/v) and untinted 70% isopropyl alcohol (v/v). The assignment will be quasi-randomised. Volunteers will be marked and washed in a random order at volunteer discretion, and liquids will be selected at random at investigator discretion, ensuring three limbs are washed with each liquid. The study will take place in a surgical operating theatre in a private hospital in Melbourne, Australia. The study will be conducted by an orthopaedic registrar who will apply the pen marks and surgical prep.