Short for hemodialysis, dialysis is the most common treatment for chronic kidney failure. Healthy kidneys effectively remove excess fluid, minerals and waste from the blood to keep it clean and prevent disease. When the kidneys fail, they can no longer filter wastes from the blood. Dialysis does the kidneys’ job for them: blood is removed from a vein in the patient’s arm or leg, circulated through a filtering machine, and returned to the body through an artery.
Because veins tend to have weak blood flow, doctors often connect one of the patient’s nearby arteries to the vein being accessed for dialysis. This increases blood flow and strengthens the vein, which in turn allows more blood to flow. The vein’s increased strength and capacity helps create a durable access site and provide ample blood flow for patients undergoing long-term dialysis.
Dialysis treatments are usually administered three times a week for three to five hours. When beginning treatment, it is important for patients to determine the most appropriate point of vascular access with their doctor, which is the site on the body where blood is removed and returned during dialysis. This area is usually prepared a few weeks before dialysis begins to allow for more efficient removal and replacement of your blood with fewer complications.
There are three basic kinds of vascular access for dialysis treatments, including: arteriovenous (AV) fistula, AV graft and venous catheter. Your doctor will determine which type of access is most appropriate for you based on a thorough evaluation of your condition.
An AV (arteriovenous) fistula is the surgical connection of an artery to a vein to create a stable access site and provide ample blood flow for patients undergoing long-term dialysis treatments. They are created during a minor outpatient procedure that is performed under local anesthesia.
Although they typically take three to six months to mature, fistulas are considered the “gold standard” option for dialysis access. Doctors prefer to use fistulas over alternative methods such as artificial grafts and catheters because fistulas tend to be more durable and have a lower risk of complications.
If you have small veins that won’t develop properly into a fistula, you can get a vascular access that connects an artery to a vein using a synthetic tube, or graft, implanted under the skin in your arm. The graft becomes an artificial vein that can be used repeatedly for needle placement and blood access during hemodialysis. A graft doesn’t need to develop as a fistula does, so it can be used sooner after placement, often within 2 or 3 weeks.
Venous Catheters for Temporary Access
If your kidney disease has progressed quickly, you may not have time to get a permanent vascular access before you start hemodialysis treatments. You may need to use a venous catheter as a temporary access. Catheters are not ideal for permanent access.
As with any type of treatment, there are certain risks associated with all three types of vascular access, including infection, blood clotting, and low blood flow. These complications are considered minor and tend to occur most often in venous catheters. Your doctor may prescribe medications to correct these problems or may need to remove the access point with additional surgery.
Our doctors have many years of experience performing dialysis access procedures, and take certain precautions to reduce the risk of complications.