Blood culture contamination rates after skin antisepsis with chlorhexidine gluconate versus povidone-iodine in a pediatric emergency department

Abstract

Objective: To determine blood culture contamination rates after skin antisepsis with chlorhexidine, compared with povidone-iodine.

Design: Retrospective, quasi-experimental study.

Setting: Emergency department of a tertiary care children's hospital.

Patients: Children aged 2-36 months with peripheral blood culture results from February 2004 to June 2008. Control patients were children younger than 2 months with peripheral blood culture results.

Methods: Blood culture contamination rates were compared using segmented regression analysis of time-series data among 3 patient groups: (1) patients aged 2-36 months during the 26-month preintervention period, in which 10% povidone-iodine was used for skin antisepsis before blood culture; (2) patients aged 2-36 months during the 26-month postintervention period, in which 3% chlorhexidine gluconate was used; and (3) patients younger than 2 months not exposed to the chlorhexidine intervention (ie, the control group).

Results: Results from 11,595 eligible blood cultures were reviewed (4,942 from the preintervention group, 4,274 from the postintervention group, and 2,379 from the control group). For children aged 2-36 months, the blood culture contamination rate decreased from 24.81 to 17.19 contaminated cultures per 1,000 cultures (P < .05) after implementation of chlorhexidine. This decrease of 7.62 contaminated cultures per 1,000 cultures (95% confidence interval, -0.781 to -15.16) represented a 30% relative decrease from the preintervention period and was sustained over the entire postintervention period. No change in contamination rate was observed in the control group (P = .337).

Conclusion: Skin antisepsis with chlorhexidine significantly reduces the blood culture contamination rate among young children, as compared with povidone-iodine.