An AV fistula (Arteriovenous fistula) is a connection formed between an artery and a vein that occur in abnormal conditions. Arteries are the blood vessels that carry oxygenated blood to body cells and veins carry to collect the deoxygenated blood from cells. Usually, the blood flow starts from the arteries to the capillaries. Then from the capillaries, it flows to the veins. The oxygen and nutrients present in the blood travel from the capillaries to tissues in our body. This is normal physiology. But whereas in the case of an AV fistula, the blood flow directly happens from an artery to a vein bypassing capillaries. It passes only through some capillaries which results in the tissues present below these capillaries receiving less amount of blood. Know more about dialysis fistula.
Legs are the common spot for AV fistulas where it happens usually. But it can grow in any part of our body. For patients with kidney disease, this AV fistula is surgically created for dialysis purposes. This AV fistula which develops naturally in our body has to be treated with medical care. It may grow large and when they are untreated, it paves way for other serious complications. When going through dialysis, the AV fistula which is created by the nephrologist is monitored periodically. An AV fistula is well known to be the most preferred methodology to gain access for vascular circulation in patients who require hemodialysis. The AV fistula which develops in the kidney is termed Renal arteriovenous fistula (AVF)
Kidney dialysis is a medical methodology being followed in kidney patients where the blood is purified, and the toxins are removed manually when the kidneys are not working to carry out this process naturally. A common access point is created by the process of dialysis fistula to carry out this dialysis procedure. An artery and a vein are connected in this procedure. The dialysis fistula is usually created in the forearm. This method is known to be the most preferred method for dialysis as this reduces the risk of blood clotting and other infections.
Procedure for Dialysis Fistula
- The patient will stay awake throughout this procedure, so the patient is given local anesthesia before starting this procedure which prevents the side effects of going for general anesthesia.
- The fistula is usually created in the non-dominant arm which means if you are a right-handed person, then the fistula is created in your left arm.
- A small cut is made in the desired arm. The artery is then joined to the vein which results in a rise in the blood flow in the vein.
- This makes the vein bulge, grow stronger and larger. The open area is then stitched to close it and these stitches are dissolvable and maybe fade within 10 days from the date of surgery.
- Since this dialysis procedure has to be carried out several times a week, it is mandatory to make sure that the vein is strong and large to carry out this process effectively.
- The blood must flow in the vein in a good condition without any interruption. So, the patient should avoid wearing tight clothing over this area. The pulse should be checked daily in the arm where the fistula is created to ensure that there is no interruption or blockage in the vein.
What is the time required for the AV fistula to get cured and ready for the dialysis procedure?
- To make sure the dialysis process goes well in an effective manner, it is mandatory that the vein has to be big, strong, and mature enough to carry out this procedure.
- So usually, the fistula is created 6 months before starting the dialysis procedure, which allows enough time for the vein to become mature.
- In this maturation period, the vein grows bigger, the walls grow stronger, and makes it thick due to the high blood flow created as a result of this fistula.
- It may take around 6 – 8 weeks for the vein to become capable of performing the dialysis.
- The nephrologist or the nurse will check your fistula periodically and they will let you know once the vein is ready.
- Your nurse will educate you about the basic caretaking procedures like how it should feel and sound so that if there is any change in the rhythm, you can figure it out yourself and can be treated at the right time.
Benefits of having a AV Fistula for Dialysis
- AV fistula is known to be the best and effective procedure to carry out haemodialysis for a prolonged time.
- AV fistula is likely to be more helpful for efficient dialysis compared to other procedures. Here the blood flow will be quicker and without any interruptions. This helps for long-term health and increases survival rates.
- AV fistula is internal and reduces the risks of external infections. This allows the patients to swim, have a shower, and involve in water sports.
Risks of having a AV Fistula for Dialysis
- Fistula is generally safe and recommended but still, there are some risks in this. Sometimes the fistula may clot resulting in blockage in the blood flow. In most cases, the blockage can be removed but in rare cases, it cannot be removed. We have to create another fistula in the other arm.
- Steal syndrome: When there is a high blood flow from an artery directly to the vein, there might be chances that the blood supply to the hand and fingers may reduce. This results in the fingers becoming cold and numb causing pain in the fingers. It can also lead to a reduction in the blood supply to the nerves to the hand, which makes the hand weak.
- The cut wound created when creating a fistula might get infected in some cases resulting in the intake of antibiotic injections.
- Sometimes there might be an abnormal swelling in the arms where the AV fistula is created. It can be cured by performing some fistula exercises like raising the arm to above the level of the heart, exercising the fingers, etc.,
Simple AV fistula care tips
- Keep your hands especially the fistula area clean and hygienic. It is advised to wash it repeatedly at regular intervals and especially before dialysis.
- Avoid wearing ornaments and watch in the arm where the fistula is created, avoid wearing tight dresses which may block the blood flow.
- Avoid sleeping by the side of your body and keep your arm free from pressure.
- Check the pulse and vibration of the fistula regularly, if you feel any change in that, immediately reach out to your nephrologist.
- Never take blood tests or check blood pressure in the arm where the fistula is created as it may lead to the AV fistula to damage or clot.
- Avoid putting pressure on the arm, never lift heavy objects which may put heavy pressure on the fistula and they may damage due to this.