The clinical effectiveness and cost-effectiveness of central venous catheters treated with anti-infective agents in preventing bloodstream infections: a systematic review and economic evaluation.

OBJECTIVES: To assess the clinical effectiveness and cost-effectiveness of central venous catheters (CVCs) treated with anti-infective agents in preventing catheter-related bloodstream infection (CRBSI). DATA SOURCES: Major electronic databases were searched from 1985 to August 2005. REVIEW
METHODS: The systematic clinical and economic reviews were conducted according to accepted procedures. Only full economic evaluations (synthesis of costs and benefits) comparing the use of anti-infective central venous catheters (AI-CVCs) with untreated CVCs or other treated catheters were selected for inclusion in the economic review.
RESULTS: A total of 32 trials met the clinical inclusion criteria. Seven different types of AI-CVC were identified, with the most frequently tested being chlorhexidine and silver sulfadiazine (CHSS) (externally treated), CHSS (externally and internally treated) and minocycline rifampicin (internally and externally treated). In general, the trials were of a poor quality in terms of reported methodology, microbiological relevance and control of confounding variables. The pooled result suggests a statistically significant advantage for AI-CVCs in comparison to standard catheters in reducing CRBSI [odds ratio (OR) 0.45, 95% confidence interval (CI) 0.34 to 0.60, 24 studies, I-squared = 0%, fixed effects]. Analysis by subgroups of catheters demonstrates that antibiotic-treated catheters and catheters treated internally and externally decrease CRBSI rates significantly (OR 0.26, 95% CI 0.15 to 0.46, six studies, I-squared = 0%, fixed effects, and OR 0.43, 95% CI 0.26 to 0.70, nine studies, I-squared = 0%, fixed effects, respectively). Catheters treated only externally demonstrate a wider CI and non-significant effect (OR 0.67, 95% CI 0.43 to 1.06, nine studies, I-squared = 0%, fixed effects). A treatment effect was also found for trials with an average duration of between 5 and 12 days, and for the one study with a mean duration of over 20 days. There was a statistically significant treatment effect for both femoral and jugular insertion sites and for those studies reporting a mix of insertion sites. The treatment effect was not observed in trials using exclusively subclavian insertion sites. Of the four trials that compared treated catheters, one reported a benefit of antibiotic-treated catheters over catheters treated externally with CHSS. All three sensitivity analyses testing for study design differences reported a statistically significant treatment effect. The review was limited owing to the quality of the trials included, marked differences in the definitions and methods of diagnosis of CRBSI, and inconsistent reporting of risk factors and patient population factors. Furthermore, two-thirds of trials were commercially funded. The economic performance (cost-effectiveness and potential cost-savings) of using AI-CVCs to reduce the number of CRBSIs in patients requiring a CVC was also reviewed. Results show that the use of AI-CVCs instead of standard CVCs can lead to a reduction in CRBSIs and decreased medical costs. To complement the reviews, a basic decision-analytic model was constructed to explore a range of possible scenarios for the NHS in England and Wales. Results show that for every patient who receives an AI-CVC there is an estimated cost-saving of 138.20 pounds. The multivariate sensitivity analyses estimate potentially large cost-savings, depending on the size of the population, under a wide range of cost and clinical assumptions. However, those considering the purchase of AI-CVCs should ensure that their patient populations and the important characteristics of local clinical practice are indeed similar to those described in this economic evaluation.
CONCLUSIONS: Overall, AI-CVCs are clinically effective and relatively inexpensive and therefore their integration into clinical practice can be justified. However, the use of these anti-infective catheters without the appropriate use of other practical care initiatives will have only a limited success on the prevention of CRBSIs. Comparative trials are required to determine which, if any, of the treated catheters is the most effective. Pragmatic research related to the effectiveness of bundles of care that may reduce rates of CRBSI is also warranted.