Alternatives to Hemodialysis Catheters
When kidneys fail, it is necessary to find alternative ways to remove toxins and excess fluid from the body, imitating kidney function. This is done either by hemodialysis, circulating the blood through a machine external to the body, filtering it and then returning the clean blood to the body, or via peritoneal dialysis, using blood vessels in the abdomen to substitute for the kidneys.
Hemodialysis requires access to blood vessels. These vessels must be strong enough to withstand repeated cannulation. Vascular access can be achieved via catheter, graft or fistula placement.
Catheters – Because dialysis catheters are straight forward, available for immediate use and have minimal short term complications, the catheters are generally used as a temporary central venous access. Cuffed or tunneled catheters may also be used in cases where the patient does not have a functional permanent dialysis access. In the long term, catheters carry a high risk of infection and of thrombosis and stenosis, often causing permanent damage to the blood vessel, and are considered to be the least favorable option for long term vascular access. Catheters are removed once fistula or graft can be used reliably. The rate of catheter infection is 8 times higher than with a fistula, and 4 times higher than with a graft.
Because of the high infection rate and morbidity, alternatives to catheters should be used as permanent vascular access during hemodialysis.
Common Alternatives to catheters during hemodialysis
Grafts – An arteriovenous (AV) graft is a method of gaining vascular access for patients without the suitable veins needed for fistula creation. An artery and vein are surgically connected using a piece of artificial tubing. The AV graft will be placed in the arm or leg depending on the size and condition of the arteries and veins. The AV graft can be used 2-3 weeks after the surgery, and have a life span of approximately 3 years. There is a relatively high risk of infection and clotting with an AV graft and special care and monitoring should be done.
Fistulas – Arteriovenous (AV) fistulas are considered to be the gold standard for vascular access in hemodialysis patients, and the first choice whenever possible. The AV fistula is created by surgically attaching a vein to an artery. The increased blood flow allows the vein to grow larger and stronger in a process called maturation. After approximately 4-12 weeks, the vein is strong enough to undergo repeated cannulation. AV fistulas have the fewest complications and hospitalizations, in comparison to other access modes. However, despite its clear benefits, AV fistulas have some risks and early fistula failure occurs in over 40% of fistulas. In an attempt to attack the problem of non-maturation VasQ™ was designed. VasQ™ provides external support, allowing for the regulation of blood flow by constraining and shaping optimal geometrical parameters of the fistula, reinforcing and shielding the perianastomotic vein against high pressure, wall tension, and flow levels. In a safe and effective way VasQ™ enhances maturation and improves patency, thus reducing the risk of fistulas failing to mature. Read more about VasQ™ and improving AV fistula maturation at our website.