Evaluation of donor arm disinfection techniques

Background and Objective To validate a standardized optimal national proced ure for donor arm disinfection. Materials and Methods A direct swabbing and plating technique was used to e numerate bacteria present on the arm pre- and postdisinfection. Twelve dono r arm disinfection techniques were evaluated. Results The Medi-Flex Adapted method, consisting of a two-stage process wit h an initial application of isopropyl alcohol followed by tincture of iodin e, produced the best arm disinfection. A percentage reduction in bacterial counts of 99.79% (logarithmic reduction of 2.67) was obtained. Postdisinfec tion, 70% of donors had bacterial counts of zero, and 98% had counts of 10 or less. Conclusion The Medi-Flex disinfection method offers the English National Bl ood Service a validated, optimal 'best practice' disinfection technique and should contribute significantly to the reduction in risk of transmission o f bacteria by transfusion.