Central venous catheters (CVC)

Central venous catheters (CVC) for hemodialysis may be nontunneled (designed for acute episodes and temporary duration) or tunneled (for more chronic use over a longer duration). Acute CVC are designed to be placed with a minimum amount of effort. They generally have double lumens, no subcutaneous cuff or locking device and utilize a short linear tunnel. Tunneled CVC are dual lumen most often composed of silicone, polyurethane, polyethylene or polytetrafluethylene (PTFE) and contain a subcutaneous Dacron cuff for tissue in-growth or a plastic ‘‘grommet’’ to immobilize the catheter below the skin surface¹. CVC are typically placed percutaneously into a large central vein (internal jugular or subclavian vein) through the superior vena cava (SVC) with the goal of placing the tips of the catheter at the junction of the SVC and the right atrium1. Alternative venous access points are external jugular, subclavian, and femoral veins. Right sided catheters malfunction less often than left sided catheters and subclavian catheters should be avoided to help prevent subclavian stenosis².

CVC afford the luxury of immediate access to the circulation without the requirement for cannulation; however, these devices are plagued by their propensity for infection, thrombosis, inadequate blood flow, damage to large central veins, overall cost and increased mortality risk which make their use problematic. Patients with catheters have a significantly higher mortality risk than patients with arteriovenous fistula (AVF) or arteriovenous grafts (AVG). In one study of 616 incident dialysis patients, the adjusted relative hazards of death were 1.5 for catheters (95% CI 1.0-2.2) and 1.2 for grafts (95% CI 0.8-1.8) when compared to AVF^{3, 4}. An analysis of the HEMO study, using time-dependent Cox regression adjusted for clinical center and the seven predefined clinical variables, found a significantly higher likelihood of infection-related death among patients dialyzing with CVC compared with those dialyzing with AVF (RR, 2.30 [95% CI, 1.45 to 3.64]; p < 0.001). Similarly, the likelihood of first infection-related hospitalization or infection-related death was significantly higher for patients dialyzing with CVC compared with those dialyzing with AVF (RR, 1.85 [95% CI, 1.47, 2.33]; p < 0.001)⁵. CVC related bacteremia averages between 3.4 and 5.5 incidences per 1000 catheter days with the resultant potential for the development of complications including paravertebral abscess, endocarditis and death⁶. CVC are associated not only with greater mortality and hospitalization rates due to sepsis, but also with greater rates of all-cause hospitalization. The annual Medicare expenditures for patients with a CVC average approximately $20,000 more than for patients with a AVF^{7, 8, 9}. For these reasons, CVC reduction is one of the primary actionable targets for improving overall hemodialysis patient outcomes.

References:

1. Ash SR. The evolution and function of central venous catheters for dialysis. Sem in Dial 14:416-424, 2004
2. KDOQI Clinical Practice Guidelines for Vascular Access. Am J Kidney Dis 48(Suppl 1):S176-S273, 2006
3. Oliver MJ. Chronic hemodialysis vascular access: Types and placement. Retrieved from www.uptodate.com on January 14, 2009
4. Astor BC, Eustace JA, Powe NR, Klag MJ, Fink NE, Coresh J. Type of vascular access and survival among incident hemodialysis patients: The choices for healthy outcomes in caring for ESRD (CHOICE) study. J Am Soc Nephrol 16:1449-1455, 2005
5. Allon M, Depner TA, Radeva M, Bailey J, Beddhu S, Butterly D, Coyne DW, Gassman JJ, Kaufman AM, Kaysen GA, Lewis JA and Schwab SJ. Impact of dialysis dose and membrane on infection-related hospitalization and death: Results of the HEMO study. J Am Soc Nephrol 14:1863-1870, 2003
6. Nassar GM, Ayus JC. Infectious complications of the hemodialysis access. Kidney Int 60:1-13, 2001
7. Lacson E, Lazarus JM, Himmelfarb J, Ikizler TA, Hakim RM. Balancing fistula first with catheters last. Am J Kidney Dis 50:379-395, 2007
8. Manns B, Tonelli M, Yilmaz S, Lee H, Laupland K, Klarenbach S, Radkevich V, Murphy B. Establishment and maintenance of vascular access in incident hemodialysis patients: A prospective cost analysis. J Am Soc Nephrol 16:201–209, 2005
9. USRDS 2006 Annual Data Report: Atlas of Chronic Kidney Disease and End-Stage Renal Disease in the United States, National Institutes of Health, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD, 2006

 
P/N 101042-01 03/2009