AV fistula for hemodialysis
What is hemodialysis
Hemodialysis is a procedure where a dialysis machine and a special filter called an artificial kidney, or a dialyzer, are used to clean your blood. This procedure is done when you have a severe kidney failure.
Healthy kidneys work as filters for ridding the body of waste and toxic substances, and returning vitamins, amino acids, glucose, hormones and other vital substances into the bloodstream. Among other things this kidney function helps regulate your blood pressure and balance important minerals, such as potassium, sodium, and calcium, in your blood.
When your kidneys don’t function properly this affects the whole organism and body needs outside help – hemodialysis.
What is AV fistula – arteriovenous fistula
AV fistula (arteriovenous fistula) is an artificial connection made between artery and vein. This connection is usually made in your arm, but sometimes it can be in your leg.
With an AV fistula, blood flows from the artery directly into the vein, increasing the blood pressure and amount of blood flow through the vein. The increased flow and pressure causes the veins to enlarge and then they are capable of delivering the amount of blood flow necessary to provide an adequate hemodialysis treatment.
AV fistulas are the preferred vascular access for long-term dialysis because they last longer than any other dialysis access types, are less prone to infection and clotting, and can be relied upon for predictable performance.
How is an AV fistula created
The first step in AV fistula creation is to evaluate your blood vessels (veins and arteries), to ensure they are healthy enough to support a fistula. This is done by physical exam and ultrasound, or possibly and angiogram.
These tests are often referred to as “vessel mapping” and they will determine whether or not your blood vessels are able to support an AV fistula.
To create an AV fistula, the doctor will administer local anesthesia to the chosen access site. Next, he will make a small incision, allowing access to the selected arteries and veins after which he will make a surgical connection between an artery and a vein. After the AV fistula has been created, it will take several weeks, in some cases a month or longer, for the fistula to mature to the point where it will be able to be used for your hemodialysis treatments.
How should you prepare for this procedure
It’s important to tell your doctor if you are on any blood thinner medications such as Aspirin, Warfarin, Clopidogrel, DOACs etc.
The night before the procedure you should have a light meal. You shouldn’t drink any alcoholic beverages at least 24h before the procedure. Do not eat any solid food after midnight.
On the morning of procedure, take only the medications that your doctor told you to take with a sip of water.
Be sure you have someone to take you home. Anesthesia and pain medicine will make it unsafe for you to drive or get home on your own.
Recovering from the procedure
This procedure does not require an overnight hospitalization. In general, you should be able to go home a few hours after the procedure is completed.
You will be instructed to keep your access arm elevated to reduce swelling and pain at the access site. Your physician may also prescribe a painkiller to help manage any post-operative pain.
Before you are sent home, you will be given specific instructions on how to care for your access.
Complications of procedure
- Local complications: bleeding, venous hypertension, Aneurysm/pseudoaneurysm/megafistula. Infection. Neuropathy. Stenosis/Thrombosis.
- Primary failure and failure of mature AV fistula.
- Ischemia and other systemic problems. Dialysis access steal syndrome and ischemic monomelic neuropathy.
How does the patient care for arteriovenous fistula
You will need to protect your access point. Wash the area around your access with soap and warm water every day. Check the area for signs of infection, such as warmth or redness. If you notice any of these signs go to your doctor immediately.