The risk of cross-infection when marking surgical patients prior to surgery - review of two types of marking pens.

Introduction: Two types of marker pens were compared to find whether they produced different risks of infection transmission over different time intervals.

Patients And Methods: Twenty-four patients were marked according to the type of surgery: each had a set of new dry white-board marker (DWM) and a permanent marker (PM) pen. Once used, their tips were used to inoculate blood agar plates at different time intervals.

Results: At 0 min, 96% of the DWM pens and 29% of the PM pens were positive of growth. At 3 and 10 min, all of the DWM pens remained positive. The rate dropped to 16.67% in 3 min down to none at 10 min for the PM pens.

Conclusions: DWM pens carry a significant risk of transmitting infection between patients. It is recommended that they are not used in marking. PM pens should not be used between patients in less than a 10-min interval.