Dialysis access is achieved through one of three procedures used to prepare a patient for dialysis treatments. The procedures include insertion of a fistula, graft or catheter that will be used to connect dialysis equipment to the patient’s blood supply.
The most common type of dialysis access is a fistula. A fistula is created during a minor surgical procedure and creates a passageway using the patient’s own tissue to connect a vein to an artery that is nearby. It is typically in the arm. This creates a large blood vessel which increases the speed of the blood flow and improves the efficiency and expediency of dialysis; a treatment for removing waste and extra fluid from the blood when the patient’s kidneys have failed—usually as result of kidney disease.
Needles are used to remove the blood so it can be filtered through the dialysis machine and the purified blood is quickly returned to the patient by needle insertion. It must be placed several months before a patient begins dialysis in order to ensure the vein has time to mature and provide increased blood flow. The time period for maturation of the fistula is typically between three and six months.
Because the fistula is created with the patient’s own tissue, this procedure is likely than the others to encounter issues with infection and clotting and is generally the preferred choice for permanent vascular access.
A graft is the second most common choice for dialysis access. A minor surgical procedure is needed to place a small surgical tube which connects the vein and a nearby artery. The graft is usually inserted in the bend of the arm or the upper arm, but it may also be placed in the leg or chest wall. A graft is normally healed and ready for dialysis use in two to six weeks following placement. Grafts are often used when a patient has small veins that will not develop a fistula properly.
The third option for dialysis access is placement of a catheter. A catheter is often used for temporary access in cases where patients must start dialysis immediately and there is not time to wait for the more permanent vascular access that is granted with a fistula and graft. A catheter is a tube that is inserted in the vein of the chest, neck or leg (near the groin) of a patient. It is two-chambered and allows for two-way flow of blood which eliminates the necessity of needle insertion.
It is not ideal for permanent access due to the higher risk of infection and clotting – as compared to fistula and graft placement. However, it can be used for extended periods of time when fistula and graft surgery is unsuccessful. In these cases the catheter will be tunneled under the skin to increase comfort and reduce infection risk, but a tunneled catheter is still prone to infection.
To reduce risk of infection for fistula and graft access, it is important that a patient takes special care of the site. Patients must monitor the site for signs of infection, redness, and excess bleeding. It is also a good idea to wash the site with antibacterial soap daily and try to prevent scratching or damage to the skin surrounding the site. If anything unusual is noted like redness, swelling and heat, a patient should contact the dialysis care provider at once.
As for catheter care, patients must ensure the site stays clean and dry and that a clean dressing is applied daily. A protective cover should be used when the patient showers. It is important to notify the dialysis care provider immediately if the patience notices that the catheter’s placement has changed or if the edge (cuff) is showing from under the skin.