Chlorhexidine Baths Protect Patients in the ICU

Yael Waknine

February 08, 2013

Bathing hospital patients with chlorhexidine-impregnated wipes improves infection control in critical care units plagued by methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococcus (VRE), according to a study published online February 6 in the New England Journal of Medicine.

Michael Climo, MD, from the Hunter Holmes McGuire Veterans Affairs Medical Center and the Virginia Commonwealth University Medical Center, Richmond, Virginia, and colleagues found that the daily chlorhexidine bathing decreased cases of MRSA and VRE colonization or infection by 23% (5.10 vs 6.60 cases per 1000 patient-days; P = .03) compared with daily bathing using nonantibacterial washcloths. The intervention also reduced the incidence of nosocomial bacteremia by 28% (4.78 vs 6.60 cases per 1000 patient-days; P = .007).

"Based on our results, daily chlorhexidine bathing constitutes a simple, low-cost measure that is easy to implement and is effective in combating the growing problem of drug-resistant bacteria," study author Edward Wong, MD, also from the Hunter Holmes McGuire Veterans Affairs Medical Center and the Virginia Commonwealth University Medical Center, said in a Veterans Affairs news release.

"Although the practical improvement is not huge, every little bit helps, and the risk of the treatment is nearly zero. So here you have modest benefit for essentially no risk, generally a good trade-off," said Christopher Johnson, MD, who was not involved in the study.

"If I practiced in a unit that had high infection rates I'd consider [using] it," Dr. Johnson told Medscape Medical News. "I'd also consider it for patients who have prolonged stays in the [intensive care unit (ICU)] because their risk of colonization with bad bugs goes up relentlessly the longer they are there."

Dr. Johnson is president of Pediatric Intensive Care Associates, PC, in Santa Fe, New Mexico, and medical director of the pediatric ICU of CentraCare Health Systems in St. Cloud, Minnesota.

Cumulative Benefit

For the study, 9 ICUs (including 1 bone marrow transplant unit) in 6 hospitals were randomly assigned to use 2% chlorhexidine-soaked washcloths or nonantimicrobial washcloths when bathing patients during a 6-month period; units then switched over to the other method for 6 months. Samples were obtained from 7727 participants up to 48 hours postadmission and on discharge.

Results showed that the intervention significantly decreased the overall rate of VRE acquisition by 25% (3.21 vs 4.28 cases per 1000 patient-days; P = .05); MRSA acquisition dropped by 19%, but the effect did not reach statistical significance (1.89 vs 2.32 cases per 1000 patient-days; P = .29).

Use of chlorhexidine wipes was linked to a 31% decrease in the overall incidence of primary bacteremia (3.61 vs 5.24 cases per 1000 patient-days; P = .006), and Kaplan-Meier estimates revealed a significant cumulative benefit (P = .02). The relative risk of primary infection after 1 week was 0.69 (95% CI, 0.47 - 0.99) for patients in the intervention group compared with those in the control group. For patients in the ICU for more than 14 days, the relative risk was 0.51 (95% confidence interval [CI], 0.30 - 0.87) in the intervention group compared with in the control group.

"This makes good sense, because we know the longer a patient is critically ill in the ICU (often getting broad-spectrum antibiotics), the more likely it is this colonization happens. And colonization is the first step to invasive infection," Dr. Johnson noted.

Among patients with central lines, use of chlorhexidine reduced the risk for bacteremia by 53% (1.55 vs 3.30 cases per 1000 catheter-days; P = .004), including infections caused by gram-positive organisms (0.89 vs 1.76 cases per 1000 catheter-days; P = .05) and those involving fungi (0.07 vs 0.77 cases per 1000 catheter-days; P < .001).

This study was supported by the Centers for Disease Control and Prevention and Sage Products. Dr. Climo received grant support from Sage Products. One coauthor received fees from Centene, C.R. Bard, Cardinal Health, Sagentia, and 3M Health Care and grant support from Cubist Pharmaceuticals and bioMérieux; one coauthor has disclosed board memberships for Hospira and Pfizer and received grant support from Merck; and one coauthor served as an unpaid consultant for Sage Products and received grant support from the Foglia Family Foundation. The other authors and Dr. Johnson have disclosed no relevant financial relationships.

N Engl J Med. 2013;368:533-542. Abstract