By Shawn Gentry
It has been well established that measures to prevent nosocomial infectionsbegin well before the surgical procedure. During the preoperative phase, hairremoval and the proper use of topical antiseptics for bathing, hand scrubbing,and site preparation are considered important in reducing the opportunity for anosocomial infection.
Some of the preoperative measures performed in or near the operating room arehelping to keep the postoperative hospital stay short and uneventful, as relatedto nosocomial infections. First, it is now recommended to avoid hair removal or,if necessary, remove hair with clippers or depilatories rather than a razor.Studies indicate that shaving with a razor can injure the skin and increase therisk of infection. If shaving is necessary, it should be performed immediatelybefore the operation and followed with the use of a preoperative antiseptic.Secondly, the skin at the operative site is thoroughly cleaned to removesuperficial flora, soil, and debris before the operation to reduce the risk ofcontaminating the wound with a patient's skin flora. Finally, immediately beforethe surgery, a preoperative antimicrobial skin preparation is applied to thepatient's skin to kill or inhibit more adherent, deep, resident flora. A patientpreoperative skin preparation is defined by the U.S. Food and DrugAdministration (FDA) as "a fast-acting, broad-spectrum and persistentantiseptic containing preparation that significantly reduces the number ofmicro-organisms on intact skin."
The list of antimicrobial agents commercially available as principal activeingredients for use in patient preoperative skin-preparation products isrelatively short and currently includes alcohols, chlorhexidine gluconate (CHG),and iodophors such as povidone iodine (PVPI). Only two of these antimicrobialclasses, 1) alcohols (specifically ethyl alcohol and isopropyl alcohol) and 2)iodine and iodophors, are currently classified Category 1 (safe and effective)and allowed for patient preoperative skin preparation under the FDA's TentativeFinal Monograph for Healthcare Antiseptics.
Alcohol
While very effective antimicrobial agents when used in sufficientconcentration (60-90%), alcohols appear to act by rapid denaturation ofbiomolecules (DNA, RNA, lipids, etc.) essential to microbial growth anddevelopment. Alcohols prove very effective against a broad spectrum ofmicroorganisms, including gram-negative and gram-positive bacteria, fungi, andviruses, including the HIV, hepatitis B, and respiratory syncytial viruses.Alcohol application provides the fastest and greatest reduction in microbialcounts on the skin. A one-minute immersion, or scrub, with alcohol proves aseffective as four- to seven-minute applications of other antiseptics andrequires hours for the bioburden to return to pre-scrub levels. Bacterialresistance to alcohols at high concentrations is extremely low to almostnon-existent.
With respect to their use in surgical site preparation or skin antisepsis,three alcohols have been studied extensively: ethyl alcohol, isopropyl alcohol,and n-propyl alcohol. Studies conclusively show greater antimicrobialeffectiveness for n-propyl alcohol than for isopropyl or ethyl alcohol atconcentrations below 60 percent; however, at higher concentrations, structuraldifferences become less of a factor in relative efficacy. Safety profiles forthese alcohols have been well characterized, and although toxicity has beenreported when sponging febrile children with isopropyl alcohol, alcohols aregenerally considered among the safest antiseptics for topical use.
In Europe, alcohol-based preparations, recognized as having greater immediateantimicrobial action than all other active ingredients, are often used forsurgical preparation of the hands. Until very recently, alcohols have not beenwidely used in the United States as surgical scrub ingredients because, despitetheir excellent, quick, and thorough antimicrobial action, they do not have anysignificant detergency for the removal of organic debris or antimicrobialpersistence in the stratum corneum. They also tend to be very drying to theskin. However, very recent developments have produced at least one surgicalscrub product (TriSeptin®) that while alcohol-based, has detergentaction, contains emollients for hand conditioning, and other factors thatproduce antimicrobial persistence beyond 24 hours. These same properties havebeen incorporated into a surgical site preparation. The resulting suspension isskin friendly, rapid acting, long-lasting, and fast drying.
