Preoperative Skin Cleansing With Chlorhexidine Gluconate

Jane C. Rothrock, DNSc, MSN, BSN, CNOR, FAAN


March 11, 2010


How effective is the 2% CHG solution for preop bathing? Are 2 baths with 2% CHG sufficient for skin antisepsis?

Response from Jane C. Rothrock, DNSc, MSN, BSN, CNOR, FAAN
Professor and Director, Perioperative Programs, Delaware County Community College, Media, Pennsylvania

An estimated 500,000 surgical site infections (SSIs) occur each year. Patients with a SSI have a 2-11 times greater risk for death than surgical patients without a SSI, and spend approximately 7-10 more days in the hospital at additional costs of $3000 to $29,000.[1] The use of an antimicrobial skin agent such as chlorhexidine gluconate (CHG) with a bath or shower works in 2 ways to prevent SSI. The simple act of mechanical friction and rinsing removes transient skin microbes. The addition of an agent such as CHG provides persistent activity, which further reduces the level of the patient’s own skin flora. For patients scheduled for a surgical procedure, the recommendation from the Association of periOperative Nurses is to use 4% CHG for bathing or showering the night before and the morning of the scheduled procedure.[2] The details of that recommendation have been previously reviewed in an article about preoperative showers and baths.[3] It is probably safe to say that using aqueous 2% CHG for 2 baths or showers is an adequate way to begin skin antisepsis in patients scheduled for surgery. This practice has been studied in relation to vascular catheter-related infection and shown to be effective.[4] Although the discussion about the addition of alcohol to the product used for cleaning the vascular catheter insertion site is ongoing, (because alcohol is an effective and rapid-acting skin antiseptic), the 2% aqueous solution is less irritating for patients to use in a shower or bath.

As noted above, controversy exists about the use of 2% CHG-based preparations for cleansing vascular catheter insertion sites. In their 2002 Guidelines for the Prevention of Intravascular Catheter-Related Infections, O'Grady and associates note that a 2% chlorhexidine-based preparation is preferred.[5] This recommendation was based on the 1991 study by Maki and colleagues that demonstrated that 2% aqueous CHG was more effective than aqueous povidone-iodine in reducing catheter-related infections.[4] During the public comment period for the 2009 updated draft guidelines for the Prevention of Intravascular Catheter-Related Infections a suggestion that practitioners "...use a greater than 0.5% alcoholic chlorhexidine gluconate-based preparation for skin antisepsis" was made.[6] Two new studies support this suggestion.

Because the patient's skin is a major source of pathogens, preoperative skin cleansing has been of great interest in the prevention of SSIs. Which skin antiseptic to use remains a topic of research. A recent prospective randomized trial involving 6 hospitals posed the hypothesis that preoperative skin cleansing with CHG and alcohol would be more protective against infection than povidone-iodine.[7] Patients scheduled for clean-contaminated surgery were randomly assigned to preoperative antisepsis with 2% CHG-alcohol (n = 409) or povidone-iodine (n = 440). Data analysis confirmed that patients in the CHG-alcohol group had a significantly lower overall SSI rate than those in the povidone-iodine group -- 9.5% vs 16.1%. The 2% CHG-alcohol was significantly more protective than povidone-iodine against both superficial-incisional (4.2% vs 8.6%) and deep incisional (1% vs 3%) infections, but not against organ-space infections (4.4% vs 4.5%). The researchers concluded that preoperative skin cleansing with CHG-alcohol is superior to povidone-iodine for preventing surgical-site infection after clean-contaminated surgery.

In a study with a different approach, a randomized, double-blind, controlled, multicenter trial was conducted to determine whether rapid identification of Staphylococcus aureus nasal carriers at the time of admission, followed by treatment with mupirocin nasal ointment twice a day for 5 days and daily baths with CHG soap would reduce the risk of hospital-associated S aureus infections.[8] The study was prompted by the knowledge that nasal carriers of high numbers of S aureus bacteria have a 3-6 times higher risk for healthcare-associated infections with this organism. Intranasal application of mupirocin has previously been shown to be effective for decolonization of S aureus and prevention of invasive infections.

Study results demonstrated a rate of S aureus infection of 3.4% (17 of 504 patients) in the mupirocin-CHG group compared with 7.7% (32 of 413 patients) in the placebo group. The effect of mupirocin-CHG treatment was most pronounced for deep SSIs -- 0.9% for the mupirocin-CHG group vs 4.4% for the placebo group. Thus, these researchers from The Netherlands drew the conclusion that rapid nasal screening for S aureus followed by decolonization of the nose and skin with mupirocin ointment and CHG soap significantly reduced hospital-acquired S aureus infections. In an accompanying editorial, infection control expert Richard Wenzel, MD, suggested that the screening protocol could be reserved for patients having cardiac surgery, receiving implants, or who are immunocompromised.[10]

To conclude, your question is a very thoughtful one. I believe it is safe to say that the use of aqueous 2% CHG for the 2 recommended preoperative baths or showers is indeed adequate to begin the process of surgical skin antisepsis.