In France about 32% of hospitalized patients have a vascular access placement. However, a common complication associated with these is catheter-related bloodstream infection (CRBI) due to the introduction of microorganisms from the skin during catheter insertion.

There is no consensus on the best way to clean the skin prior to catheter insertion, which could be a key element of CRBI prevention. The two techniques most commonly used to apply antiseptic to the skin are the concentric circle and back-and-forth techniques, but these have not been compared in clinical trials. Hence, this study conducted this comparison.

This single-center, non-comparative, randomized, matched pilot study investigated the levels of cutaneous microorganisms before and after antiseptic application using both techniques in a population of healthy French volunteers. The two application methods were used on each participant's arms at the elbow fold, with randomization for the application side (right or left). Quantification of cutaneous microorganisms was performed in a blinded manner with regard to the technique used.

From April 8 to July 17, 2019, 132 healthy volunteers participated in the study. For the whole study population, the mean initial colonization level was 2.68 log10 colony forming units (CFU)/mL (SD 0.82) before the back-and-forth technique, and 2.66 log10 CFU/mL (SD 0.85) before the concentric circle technique. The mean differences in number of microorganisms between the initial sample and the final sample were 2.45 log10 CFU/mL (95% CI: 2.29 to 2.61) for the back-and-forth technique and 2.43 log10 CFU/mL (95% CI: 2.27 to 2.59) for the concentric circle technique.

The mean difference in reduction in microorganisms between the back-and-forth technique and the concentric circle technique was 0.02 log10 CFU/mL (95% CI: –0.11 to 0.15).

There was no clinically difference in reduction of microorganisms between the concentric circle and back-and-forth techniques at the bend of the healthy volunteer's elbow, after the 30 s of drying of the antiseptic. These findings have a significant impact on time required to achieve antiseptic application before catheter insertion because there is yet no argument to justify application for 30 s, because a single concentric circle pass was much faster with similar results. Future studies should investigate the impact of skin application technique on the prevention of infectious risk associated with catheter insertion on admission to health care facilities (conventional, outpatient, or emergency) and throughout the period of stay in a health care facility.