Dialysis Access for Hemodialysis
What is dialysis access?
Dialysis access is an entrance-way into your bloodstream that lies beneath your skin and is easy to use. The access is usually in your arm or leg, and allows blood to be removed and returned quickly, efficiently, and safely during dialysis.
Dialysis, also called hemodialysis, is the most common treatment for kidney failure. A dialysis machine is an artificial kidney designed to remove impurities from your blood. During dialysis physicians use the dialysis access to circulate your blood through the machine to remove impurities and regulate fluid and chemical balances. The purified blood is then returned to you again through the dialysis access.
Creating the access portal is a minor surgical procedure. There are two types of portals:
- Fistula, which your vascular surgeon constructs by joining an artery to a vein.
- Graft, which is a man-made tube that your vascular surgeon inserts to connect an artery to a vein.
For both fistulas and grafts, the connection between your artery and vein increases blood flow through the vein. In response, your vein stretches and becomes strengthened. This allows an even greater amount of blood to pass through the vein and allows your dialysis to proceed efficiently.
In the weeks after surgery, the dialysis fistula begins to mature. The vein increases in size and may look like a cord under your skin. The whole process typically takes 3 to 6 months. Some fistulas take as long as a year or more to develop fully, but this is unusual. Once matured, a fistula should be large and strong enough for dialysis technicians and nurses to insert the large dialysis needles easily. If it fails to mature in a reasonable period of time, you may need another fistula.
You can usually begin using a dialysis graft in 2 to 6 weeks, when it is healed sufficiently. Usually fistulas are preferred to grafts because fistulas are constructed using your own tissue, which is more durable and resistant to infection than are grafts. However, if your veins are too small to use, the graft provides a good alternative.
Grafts mature more quickly than fistulas depending upon the size of the vein initially. Grafts are more likely than fistulas to become infected. Grafts usually last about 1 to 2 years, which is less than fistulas. Fistulas can often last up to 3 to 7 years. If you care properly for your graft, however, you can help it last for many years.
Typically you will have the procedure on an outpatient basis, or spend the night and go home early the next day. In most cases, your anesthesiologist will put you to sleep for this procedure. In some cases, you will be sedated and the anesthesiologist or surgeon will numb the area where the fistula or graft will go before doing the surgery.
Depending upon the quality of your artery and vein, your surgeon will try to construct the fistula with one incision using the arm that you do not use as frequently. For example, if you're left handed, your physician will place the fistula in your right arm, if possible. To perform the surgery, your physician joins an artery and a large vein under the skin. The physician divides your vein and sews it to an opening made in the side of the artery.
If you cannot receive a fistula because the vein is too small, your physician may construct a graft using a tube of man-made material. Your physician sews the graft to one of your veins and connects the other end to an artery. Your physician may place the graft material straight or form a loop under the skin either in your arm or leg.
After the operation, you should initially keep the access area raised above your heart to reduce swelling and pain. Your surgeon may recommend an over-the-counter painkiller to relieve pain, if necessary.
Complications with dialysis access include clotting, narrowing, aneurysm formation in the access itself,infection, and bleeding.
Post-surgery instructions to keep your access working
- Keep the incision dry for at least 2 days after the procedure and do not soak or scrub the incision until it has healed.
- Avoid lifting more than about 15 pounds or other activities that stressor compress the access area.
- Report pain, swelling, or bleeding immediately to your physician, especially if these symptoms are becoming worse. Some pain or swelling is common and not worrisome if decreasing, but you should tell your physician if you have bleeding, drainage or a fever higher than 101 degrees Fahrenheit.
- Continue to elevate your access area above your heart for several weeks.
You may feel some coolness or numbness in the hand with the fistula. These sensations usually lessen in a few weeks as your circulation compensates for the fistula. However, if these sensations are severe, tell your physician as soon as possible, because the fistula may be causing too much blood to flow away from your hand, a condition physicians call a “steal.”
You should perform exercises to grow and strengthen your fistula, after the pain from the surgery decreases, to make dialysis faster and easier. Your Nephrologist will recommend these exercises.
What YOU can do to keep your dialysis access healthy and functioning
DO check several times each day to make sure the access is functioning.
DO NOT carry heavy items with the arm that has the access.
DO NOT sleep on that arm.
DO NOT wear any clothing or jewelry that binds that arm.
DO NOT let anyone take blood pressure, place an IV, give injections, or draw blood from that arm.
DO keep the site of the fistula or graft clean.
DO monitor the access for signs of infection after dialysis, such as swelling.
Copyright by the Society for Vascular Surgery and NorthPoint Domain