Review of evidence for alcohol-based skin preparation agents.

To the Editor—We report that surgical site infections (SSIs) remain a major problem despite nearly a decade of national efforts to implement various practice-based recommendations targeting SSIs. According to a 2012 US Department of Health and Human Services news release, "Every day, approximately 1 in every 20 patients has an infection related to the patient's hospital care." SSIs exact a huge toll on patients and remain a leading cause of preventable deaths. SSIs are also responsible for escalating healthcare-associated financial costs. Two well-known recommended practices aimed at reducing SSIs are the administration of prophylactic antibiotics prior to surgery and the use of skin preparation agents. The prophylactic antibiotic practices recommended as part of the Centers for Medicare and Medicaid Services Surgical Care Improvement Program have been widely recommended and implemented. Multiple studies have shown that the timing of the initial dose of prophylactic antibiotics, appropriate choice of prophylactic antibiotic, and maintaining adequate serum levels of antibiotics throughout the procedure impact SSIs. However, the impact of prophylactic antibiotic practices is questionable because SSI rates have not shown a significant decline, suggesting that other preventive practices, such as use of skin preparation agents with or without alcohol embedded in them, need to be investigated further. The most commonly used skin preparation agents are iodine (eg, povidone-iodine) and chlorhexidine gluconate (chlorhexidine or CHG). Both are available with or without alcohol embedded in the skin preparation. Alcohol is readily available, inexpensive, and remains the most effective and rapid-acting skin antiseptic. Most antiseptic solutions used for degerming skin contain 1 or a combination of the active ingredients: alcohol, chlorhexidine gluconate, or iodine. Both chlorhexidine and iodophors address broad spectra of antimicrobial activity. Chlorhexidine is not inactivated by blood or serum proteins. However, iodophors may be inactivated by blood or serum proteins but exert a bacteriostatic effect as long as they are present on the skin. Alcohol's principal antimicrobial activity is achieved by denaturing bacterial proteins. Concentrations of alcohol above 60% are most effective. Both gram-negative and gram-positive bacteria are highly susceptible to alcohol. Alcohol does provide a quick germicidal kill but lacks any sustained activity.