Objectives:Vascularandepiduralcatheter-relatedinfectionscausesignificantmorbiditiesandmortalityin hospitalizedpatients.Thismeta-analysisassessedtheeffectofchlorhexidine-impregnateddressingonthe risk of vascular and epidural catheter bacterial colonization and infection. Methods: Literature search was based on MEDLINE (1966 to 1 November 2005), EMBASE and Cochrane Controlled Trials Register (2005 issue 3) databases. Only randomized controlled clinical trials comparing chlorhexidine-impregnated dressing with placebo or povidine-iodine dressing were included in this meta-analysis. Two reviewers reviewed and extracted the data independently. Results: Eight studies assessing a single type of chlorhexidine-impregnated dressing were identified and subjected to meta-analysis. The chlorhexidine-impregnated dressing reduced the risk of epidural (3.6% versus 35%, odds ratio (OR) 0.07, 95% CI: 0.02-0.31, P = 0.0005) and intravascular catheter or exit-site bacterial colonization (14.8% versus 26.9%, OR 0.47, 95% CI: 0.34-0.65, P < 0.00001) (overall 14.3% versus 27.2%, OR 0.40, 95% CI: 0.26-0.61; P < 0.0001). The use of chlorhexidine-impregnated dressing was associated with a trend towards reduction in catheter-related bloodstream or CNS infections (2.2% versus 3.8%, OR 0.58, 95% CI: 0.29-1.14, P = 0.11). Local cutaneous reactions to chlorhexidine-impregnated dressing were reported in 5.6% of the patients in three studies (OR 8.17, 95% CI: 1.19-56.14, P = 0.04), and 96% of these reactions occurred in neonatal patients. The number needed to prevent one episode of intravascular catheter-related bloodstream infection was 142 for an average period of catheter in situ of 10 days and a change of dressing every 5 days. The cost of preventing one vascular catheter-related bloodstream infection was estimated to be £298 (US$532.5). Conclusions: Chlorhexidine-impregnated dressing is effective in reducing vascular and epidural catheter bacterialcolonizationandisalsoassociatedwithatrendtowardsreductionincatheter-relatedbloodstream or CNS infections. A large randomized controlled trial is needed to confirm whether chlorhexidine- impregnated dressing is cost-effective in preventing bacterial infection related to vascular and epidural catheters.