Introduction
Antimicrobial products for antiseptic skin preparation are available in both bulk containers and as sterile single-use applications. Bulk antimicrobial solutions are still widely used in hospital environments because substantial quantities are needed, and there is a perceived cost benefit in purchasing in bulk rather than in single unit applicators. There are several indirect contributors to the total cost of a product that often are not considered, however. Handling bulk solutions requires additional procedures to reduce the risk of contamination. These procedures translate into labor costs that are not included in the total product cost. Of greater importance is the risk of contamination presented by improper handling of bulk solutions and the serious consequences on patient care. Recent innovations in sterile single-use applicators provide many advantages compared to bulk solutions. This article reviews advantages of sterile single-use applicators for skin antisepsis.

Bulk antimicrobials
Currently, most hospitals purchase antiseptic solutions in bulk containers because of their lower cost compared to sterile single-use applications. Bulk solutions often are poured into reusable multi-use containers and distributed to locations throughout the hospital. Some bulk solutions must also be diluted to the appropriate strength for skin antisepsis. Although the potential for cost savings and multiple use of bulk solutions appears to be economical and practical, their use has been associated with increased risk for contamination. Previously opened containers of povidone iodine were tested for bacterial contamination in one study. In 40 percent of multiple-use containers either the inside of the bottle cap or the povidone iodine solution was contaminated. Unopened bottles of povidone iodine were cultured as a control and were found to be uncontaminated. The study concluded that the risk for contamination of multiple-use containers increased after they were opened. As expected, the antibacterial activity of contaminated povidone iodine was diminished, resulting in less effective antimicrobial effects and the potential for introducing infection in patients.1 This study supported earlier findings of Serratia marcescens contamination in spray bottles of benzalkonium chloride solution used in a physician office. In that case, the problem of contamination was compounded by the inferior antimicrobial effects of the benzalkonium chloride. Study authors, along with the Centers for Disease Control and Prevention (CDC), concluded that in addition to better container management, the use of a more appropriate skin disinfectant, such as tincture of chlorhexidine, iodophors, or tincture of iodine, should be used.2

Contamination from containers has been linked to serious patient outcomes. An outbreak of S marcescens infection in a neonatal intensive care unit (NICU) was linked to 4-ounce containers of 1% chloroxylenol soap that were left standing in an inverted position in the NICU sink and work areas. DNA analysis determined that bacteria from infected infants, healthcare workers, chloroxylenol containers and sinks were identical. Contaminated chloroxylenol soap containers contributed to S marcescens infection in 32 infants in a 14-month period.3

Effects on hospital routines
Potential contamination of bulk solutions has led to the implementation of internal hospital procedures to minimize risk. Typical procedures are summarized below under Hospital Bulk Antiseptic Container Procedures. Normal handling practices and management of reusable containers raise concerns about product integrity and negative effects on patient care. Every time a container is opened, the risk for contamination is increased. Devices that come into contact with more than one container, such as hand-pumps, can spread contamination to other containers. The optimum approach to ensuring the correct handling of bulk solutions in reusable containers is time consuming, requiring detailed management of containers by dating, labeling and tracking them. Once the solution is discarded, the containers must be thoroughly sanitized before being reused. Some hospitals recommend additional labeling on each container to indicate the sanitation date.4-6 Another consequence of bulk solution use is the need for clean-up due to spillage. Solutions contained in bottles often are spilled onto patient gowns and bedding. Wet containers are set upon surfaces that must then be wiped down. Solution that is spilled onto the floor is messy and slick, potentially causing accidents. Although the primary rationale for purchasing bulk antiseptic solutions is lower direct costs, the indirect cost of labor to track, sanitize and label containers and the cost of cleaning spilled solution is not factored into the total cost of handling bulk solution. The most significant potential cost, however, is associated with the increased possibility of contamination and its associated risk for patient infection.

Sterile single-use applications
Antiseptics provided in sterile single-use applicators offer several advantages over antiseptic solutions. Because they are individually packaged, they are protected from contamination until they are ready to be used. Single-use applicators are produced in many sizes designed for specific uses. They contain only the amount of antiseptic that is needed for the area to be disinfected, so no solution is wasted. This also contributes to standardization of disinfection procedures. Once single applicators are used, they can be discarded without coming into contact with other equipment or surfaces, reducing the risk for contamination and the need for clean-up. Sterile single-use applicators also are expedient, saving time in preparation and application.

From a purchasing perspective, sterile single-use applicators may save time and costs associated with restocking. Because each unit is intended for a single application, it is easier to determine when supplies must be reordered, rather than counting and measuring bulk solution containers. Many different kinds of sterile single-use applicators are available and can be ordered in several types of procedural trays. This expedites appropriate stocking of each location where antiseptics are used and ensures that the correct type and amount of antiseptic is in place with no need to fill, distribute and monitor small containers of solution.

Efficacy of single sterile applicators
The primary concern of anyone using antiseptic solutions is their antimicrobial effects and their efficacy in patient care. Table 1 presents information about the efficacy of the most commonly used antimicrobials.7-9 Many of these antiseptics are available as single agents or in combinations in sterile single-use applicators, the most common being povidone iodine, chlorhexidine gluconate and alcohol preparations. Povidone iodine brands include Persist, DuraPrep, Betadine and Betadine PrepStick Plus. Chlorhexidine and alcohol products include the ChloraPrep line. Each of these agents produces clinically proven wide-spectrum antibacterial activity in sterile single-use applicators, providing the benefits of low contamination risk and rapid, easy use. Until recently, povidone iodine agents were the most commonly used skin preparation products. However, recent data have revealed superior results for chlorhexidine-based antiseptics. A meta-analysis of eight studies of vascular catheter site care demonstrated a 47 percent decrease in risk of catheter bacterial colonization and a 49 percent decrease in CRBSI among patients treated with chlorhexidine compared to povidone iodine.10,11 Costs of care and mortality decreased when chlorhexidine was used. The total healthcare cost was $111 per catheter with chlorhexidine compared to $224 per catheter with povidone iodine.10 In addition, the CDC has published guidelines that state a preference for a 2 percent chlorhexidine-based antiseptic solution for cutaneous antisepsis.12

Conclusions
Bulk solutions have been the standard of care primarily due to their lower costs per unit. Total costs do not include indirect expenditures for labor needed to properly manage antiseptic solution containers and to clean spilled and wasted solution, however. In addition, studies have demonstrated the risk of contamination of opened bulk solution containers and reusable multi-use containers. Sterile single-use applicators offer significant advantages in preventing contamination and saving time during skin preparation procedures. The antiseptic solutions that are most effective and widely used are generally available now in single-unit applications.

Although no formal economic analyses comparing bulk and sterile single-use applications currently exist, purchasing agents may wish to review internal hospital data and procedures to evaluate indirect costs of using bulk solution. Institutions that have not considered switching to single-use applications may find cost savings if they analyze both direct and indirect costs. HPN