Facts about AVF Creation for Dialysis
After a patient has been diagnosed as suffering from acute or chronic kidney failure, and dialysis has been recommended, the nephrologist will determine if the arteriovenous (AV) fistula is the ideal form of vascular access based on patient’s general health condition and the condition of the veins.
Benefits of AV fistula for kidney disease
Arteriovenous fistulas have proven to be the longest lasting, safest method of gaining vascular access for dialysis.
Normally, blood flows from arteries into capillaries and then into veins. When an arteriovenous fistula is present, blood flows directly from an artery into a vein, bypassing the capillaries. An arteriovenous fistula for kidney dialysis is the connection of a vein and an artery in order to create a long lasting site accessing the vascular system for dialysis.
AV fistulas used for kidney dialysis have been shown to improve the survival rates of patients with chronic renal failure and reduce complication rates. The AV fistula creation uses patients own veins and arteries without use of artificial material, thus lowering the risk of infection and complications.
AVF creation for dialysis
- The arteriovenous fistula is prepared by a surgeon several weeks or months before dialysis is started.
- Several weeks before the surgery the patient will be examined for circulatory abnormalities. They may be asked to undergo testing such as a Venogram (X Ray of the veins), Duplex Ultrasound (to monitor blood flow and blood vessels) or Pulse Volume Recording (measurement of blood flow through the arteries).
- The preparation of the arteriovenous fistula for kidney dialysis is done via surgery. The connection of the vein and artery provide a site through which blood can be filtered and cleaned during dialysis.
- The site of the AV fistula is usually the arm or in rarer occasions, a.The arteriovenous fistula can sit in either arms, and can be placed in the wrist, forearm, inner elbow or upper arm.
- For surgery, a local anesthetic is usually injected at the proposed site for the fistula, and the patient will be given a form of sedation for relaxation.
- A small incision will be made by the surgeon and the blood vessels will be blocked in order to stop blood flow during the procedure.
- The procedure typically takes 30-60 minutes, and is done on an outpatient basis.
- The procedure diverts a portion of the venous blood through the artery. After the vein and artery are joined the blood flow through them will increase, making the vein thicker and stronger. The connection will begin to strengthen, growing over a period of several weeks until the fistula has developed.
- The AV fistula must mature before it can be used, the process usually takes between 4 weeks to 6 months, occasionally longer. After said period of time the fistula should be strong enough to accept a dialysis needle.
- The strength of the fistula generally depends on the size and strength of the patient’s blood vessels and on the patient’s general health.
- When the fistula develops the thickened vein can be seen in the arm and a pulse can be felt. The vibration like sensation that is felt is caused by blood flowing through the fistula. It is usually felt just above the incision line, and is called a “thrill”. The thrill indicates the AV fistula is working, and should be felt for several times daily.
AV fistula Complications
Some patients may suffer complications from the AV fistula procedure, such as infection, bleeding, arm swelling and/or tingling in the fingers. Please contact medical team if such complications arise.