RESUMO
BACKGROUND: Although there is a rationale supporting that preoperative showering with 2% or 4% chlorhexidine gluconate (CHG) would decrease skin bacterial colonization, there is no consensus that this practice reduces the risk of surgical site infection (SSI). OBJECTIVES: Analyze the skin concentration of CHG after preoperative showering associated with the traditional skin preparation with CHG 4% for breast surgery. METHODS: Randomized controlled trial that included 45 patients, all candidates for augmentation mammaplasty, allocated into three groups (A: no preoperative showering; B: one preoperative showering; C: two preoperative showering with CHG 4%) in a 1:1:1 ratio. Skin swabs collection was performed right before the surgical incision. The samples were, then, sent to spectrophotometry in order to determine the skin concentration of CHG at the beginning of surgery. RESULTS: The age ranged from 18 to 61 years, with a mean of 37 years old. Group C had the lowest median concentration (0.057) followed by group B (0.060) and group A (0.072), however, with no statistical significance. The areola was the place with the lowest median concentration level (0.045), followed by the axilla (0.061) and the inframammary fold (IMF) (0.069). Still, when comparing the distribution of the sites, a statistically significant difference was found only between the axilla and the areola (p = 0.022). CONCLUSION: Preoperative showering with CHG 4% did not increase the concentration of this agent on the skin surface right before the surgical incision. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .
