Hemodialysis Arteriovenous Fistula or Graft? Here's What to Know
A vascular access is required in order to have hemodialysis. The three most common types of vascular access are: an arteriovenous fistula (AVF) created by joining a vein and an artery, usually in the arm; an arteriovenous graft (AVG) formed by connecting an artery to a vein with a tube, or a central venous catheter (CVC). Optimally, a fistula or graft will be surgically created several months before dialysis starts, in order to ensure it is ready when it is needed.
To use the graft or fistula for dialysis, two needles are placed into the vessel some distance apart. These needles connect to the dialysis lines. Blood flows out of the body through the arterial needle, through the dialysis machine and back into the body via the venous needle. At the end of dialysis, the needles are removed and bleeding is stopped by applying pressure to the needle site.
Tips for Taking Care of Your Fistula or Graft
- Keep the skin over your fistula/graft clean. Once the arm has healed following surgery, wash it daily with soap and water, and always wash it before dialysis.
- Check the ‘buzz’ or ‘thrill’ daily. Report any loss of flow immediately to your unit.
- Do not obstruct the flow of blood in the arm with the fistula or graft.
- Avoid wearing tight clothing or jewelry, including watches on your fistula/graft arm.
- Don’t loop shopping bags over your fistula/graft arm.
- Avoid sleeping on your fistula or graft.
- Avoid carrying heavy loads with this arm.
- Avoid injury to the fistula/graft arm.
- Don’t have your blood pressure taken on the arm with the fistula or graft.
- Do not allow anyone to take blood (unless during dialysis) or put a cannula in your fistula/graft arm.
Possible complications that should be reported immediately to dialysis staff:
- Bruising or swelling can occur due to the needle piercing the fistula wall after insertion resulting in swelling or bruising.
- Redness or heat, sometimes accompanied by swelling, can indicate infection.
- Allergic Reaction when your fistula becomes red, itchy or sore after applying anesthetic cream or following cleaning.
- An aneurysm or swollen area can develop over time as a result of the needles being repeatedly put in the same small area. Please rotate cannulation sites to prevent this (buttonhole needling can also avoid this). Report if the skin becomes thin and shiny or the pulse can be seen under the skin in an aneurysmal area.
- Steal syndrome will occur if your hand on your fistula arm is not receiving enough blood because it is being used by your fistula. The common symptoms are cold, numbness or pain in the access limb fingers.
- Report if you cannot feel the usual buzzing over the fistula or if it weakens indicating a reduction of blot that may be caused by a narrowing or blood clot.
- A scab over your needle site that does not heal quickly or gets larger puts you at risk of bleeding.
- Bleeding during dialysis: if blood oozes around your needles during dialysis let nurses know immediately, also if it starts taker longer than usual for bleeding to stop after needles are removed.
Profuse bleeding from a fistula or graft site unexpectedly between dialysis sessions is a medical emergency.
- Stay calm; Bleeding can usually be stopped with enough pressure in the right place. It may take more pressure than usual if the bleeding is not easily controlled.
- Seek help urgently from anyone who is around. The blood flow can be fast and make you feel faint so do not delay in alerting others. Dial 999 in the EU (911 in the US) and report “excessive bleeding from a dialysis fistula."
- Apply firm pressure over the bleeding site, use gauze and two fingers, or a bottle top or similar can help localize pressure over the bleeding site.
- Do not use too large a dressing: For example, a towel may stop you applying enough pressure in the right place.
- If the bleeding is not controlled by you pressing on it then lay down and ask someone to help by supporting your arm over your head. Check you are pressing in the right place.
- If bleeding stops before help arrives it is important that your fistula is still checked urgently as bleeding should not happen between dialysis sessions. You should attend hospital so your fistula can be checked by a fistula surgeon. Also tell your dialysis unit.
Reference: https:britishrenal.org; distilled from Information-for-Patients-AVF-and-graft-BRS-Final.pdf