As the incidence of hemodialysis increases worldwide and with renal/kidney failure patients living longer. Adequate dialysis access management has become imperative. This helps in keeping access sites viable for long-term dialysis treatments.
Hemodialysis is a method of routing blood through a dialysis machine. A dialysis machine filters the blood to remove waste. It is a lifeline for the majority of patients with renal failure. For patients who need dialysis, adequate access is often the leading factor in delivering dialysis therapy. Dialysis occurs via a central venous catheter or an access circuit (fistula or graft).
Central Venous Catheter
A central venous catheter, also called a central line, is a long, thin, flexible tube used to give medicines, fluids, nutrients, or blood products over a long period of time, usually several weeks or more. A catheter is often inserted in the arm or chest through the skin into a large vein.
Dialysis Grafts and Fistulas
A dialysis graft is created surgically in the arm or groin by connecting an artery to a vein with a tube made of woven plastic. After a month, the graft can be accessed with two needles at dialysis. While the graft is healing, most patients will need a catheter to receive dialysis. Grafts have lower infection rates than catheters, especially in the last two to three years before clotting off.
A dialysis fistula is created surgically in the arm by connecting an artery directly to a vein without the use of any plastic graft material. The vein near the connection to the artery will enlarge over a month before it becomes big enough to access with needles at dialysis. While the fistula is maturing (enlarging), patients will typically need a dialysis catheter to receive dialysis. In some cases, the vein does not enlarge on its own and must be opened using balloon angioplasty. Although fistulas are more difficult to create, they can last up to 10 years. For this reason, a dialysis fistula is preferred over a dialysis graft or tunneled dialysis catheter.
Because of the short natural lifespan of AV fistulae, many patients have historically run out of access options during prolonged chronic hemodialysis therapy. Dialysis access management of these sites may salvage sites that were historically abandoned, prolong the effective life of the access sites, save money, and prevent complications.
When a dialysis fistula or graft cannot supply the dialysis machine with a high enough flow rate to clean the blood, a fistulogram can be performed. In this procedure, IV contrast is injected through the graft to identify areas where the blood vessel is narrow. Once these narrowings are located, a small balloon is inserted into the fistula or graft and expanded to widen the blood vessel. This process is called balloon angioplasty. If angioplasty does not improve the narrowing, a metallic stent can be placed. Stents are small, metallic tubes that are used to hold the blood vessel open.
When a fistula or graft becomes completely clotted off, a de-clot procedure can be performed. The clotted graft is accessed, and contrast is injected to see the extent of the clot formation. Then several technologies can be used to remove the clot from the clotted graft or fistula. Once the clot is removed, there is usually a narrowing identified that caused the access to clot. This narrowing is usually treated with angioplasty or stenting. If a fistula or graft clots off repeatedly in a short time, a dialysis catheter will need to be surgically placed to create a new access point.
What to Expect After Dialysis Maintenance Procedures
After the procedure, you will be observed to make sure the medications have worn off.
In some cases, the site where the procedure was performed will require stitches. These will be removed before you leave the hospital. Most central venous catheters are placed with image guidance. Catheters are not ideal for long-term dialysis because of the risk for infection and blockage of the vein.
Dialysis access management also plays an important role in maintenance of an established dialysis circuit by treating narrowed segments with angioplasty balloons and stents, thereby extending the longevity of the access for dialysis. For clotted access, your doctors may restore blood flow through the circuit via a de-clot procedure. If you’re suffering from chronic renal failure, contact us at Coastal Vascular Center today. We have a range of treatment options for you.