Efficacy of surgical preparation solutions in shoulder surgery.

Background: Deep infection following shoulder surgery is a rare but devastating problem. The use of an effective skin-preparation solution may be an important step in preventing infection. The purposes of the present study were to examine the native bacteria around the shoulder and to determine the efficacy of three different surgical skin-preparation solutions on the eradication of bacteria from the shoulder.
Methods: A prospective study was undertaken to evaluate 150 consecutive patients undergoing shoulder surgery at one institution. Each shoulder was prepared with one of three randomly selected solutions: ChloraPrep (2% chlorhexidine gluconate and 70% isopropyl alcohol), DuraPrep (0.7% iodophor and 74% isopropyl alcohol), or povidone-iodine scrub and paint (0.75% iodine scrub and 1.0% iodine paint). Aerobic and anaerobic cultures were obtained prior to skin preparation for the first twenty patients, to determine the native bacteria around the shoulder, and following skin preparation for all patients.
Results: Coagulase-negative Staphylococcus and Propionibacterium acnes were the most commonly isolated organisms prior to skin preparation. The overall rate of positive cultures was 31% in the povidone-iodine group, 19% in the DuraPrep group, and 7% in the ChloraPrep group. The positive culture rate for the ChloraPrep group was lower than that for the povidone-iodine group (p < 0.0001) and the DuraPrep group (p = 0.01). ChloraPrep and DuraPrep were more effective than povidone-iodine in eliminating coagulase-negative Staphylococcus from the shoulder region (p < 0.001 for both). No significant difference was detected among the agents in their ability to eliminate Propionibacterium acnes from the shoulder region. No infections occurred in any of the patients treated in this study at a minimum of ten months of follow-up.
Conclusions: ChloraPrep is more effective than DuraPrep and povidone-iodine at eliminating overall bacteria from the shoulder region. Both ChloraPrep and DuraPrep are more effective than povidone-iodine at eliminating coagulase-negative Staphylococcus from the shoulder.