Ahead of Print: Silver-Impregnated Line Vs EVD Randomized Trial
Background: Cerebrospinal fluid (CSF) infections associated with external ventricular drain (EVD) placement attract major consequences. Silver impregnation of catheters attempts to reduce infection.
Objective: To assess the efficacy of silver catheters against CSF infection.
Methods: We performed a randomized controlled trial involving two neurosurgical centers (June 2005 to September 2009). 356 patients requiring an EVD were assessed for eligibility; 325 patients were enrolled and randomized (167 plain, 158 silver). 278 patients were analyzed (140 plain, 138 silver). The primary outcome measure was CSF infection as defined by organisms seen on gram stain or isolated by culture. Secondary outcome measures included ventriculo-peritoneal (VP) shunting.
Results: There was a significant difference in infection risk between the two study arms; 21.4% (30/140) for plain catheters vs 12.3% (17/138) for silver catheters (p = .0427; 95% CI 1.015 – 3.713). Patients who had an EVD infection had more than double the risk of requiring a VP shunt compared to patients without an EVD infection, 45.7% (21/46) vs 19.7% (45/229), respectively (p = .0002; 95% CI 1.766 – 6.682). There was also a significant difference in VP shunt risk with infection – plain (55.2%; 16/29) vs the silver arm (29.4%; 5/17); p = .0244 (95% CI 1.144 – 11.695). A multivariate analysis demonstrated that infection risk was increased by duration of EVD (odds ratio 1.160), spontaneous intracranial haemorrhage (odds ratio 4.958) and decreased by silver catheters (odds ratio .423)
Conclusion: The study provides Class I evidence that silver-impregnated catheters reduce CSF infection.
From: The SILVER (Silver-Impregnated Line Vs EVD Randomized) Trial: A Double-blind, Prospective, Randomized Controlled Trial of an Intervention to Reduce the Rate of External Ventricular Drain Infection by Keong et al.