Chlorhexidine Cleans Up Bloodstream Infections

BloodstreamThe use of no-rinse 2% chlorhexidineimpregnated cloths to bathe patients in the medical intensive-care unit has been found to reduce primary bloodstream infections by 61%, compared with soap and water.

In a 12-month study from Rush Medical Center and Cook County Bureau of Health Services in Chicago, 391 patients were assigned to receive antiseptic skin preparation with chlorhexidine gluconate, and 445 received daily baths with soap and water. The researchers found 31 primary bloodstream infections in 27 patients. Using central-line (IV catheter) days as the denominator, patients in the chlorhexidine arm were at lower risk for primary catheter-associated bloodstream infections (6.4), compared with patients bathed with soap and water (16.8) per 1,000 central-line days.

When the researchers analyzed the distribution of clinical isolates, they found a significantly higher incidence of urine isolates in the soap-and-water patients (13 isolates vs. seven) per 1,000 patient-days. Although this finding was not statistically significant, the soap-and-water arm also had more isolates from blood cultures.
Regardless of the clinical source, bathing with chlorhexidine reduced the incidence of gram-positive bacterial isolates. Recovery of isolates from other microbial categories (such as yeasts, molds, and gram-negative bacteria) was similar in both study arms.

Acknowledging concern about the increased use of antiseptics leading to microbial resistance, the researchers said that blood culture isolates recovered from patients in the chlorhexidine group had slightly higher minimum inhibitory concentrations than the isolates recovered from the soap-and-water arm; however, they add, this was a result of a reduction in the incidence of bloodstream infections by isolates that typically are inhibited by very low chlorhexidine concentrations, such as coagulase-negative staphylococci, rather than by an increase in the number of microorganisms with decreased chlorhexidine susceptibility.

The soap-and-water group of patients had a disproportionate number of primary bloodstream infections caused by coagulase-negative staphylococci. Even though these bacteria may be less virulent than some other microbial species, their recovery can be associated with substantial morbidity and mortality.

(Source: Arch Intern Med 2007;167: 2073-2079.)