Understanding Dialysis Fistulas: A Complete Guide

Introduction

When it comes to treating kidney diseases, dialysis serves as a life-saving procedure. Hemodialysis, in particular, requires the creation of a reliable access point for blood flow, which is where an arteriovenous (AV) fistula comes into play. The AV fistula, often known as a ‘dialysis fistula,’ is an integral part of the hemodialysis procedure. This comprehensive guide will delve into the specifics of what a dialysis fistula is, why it’s needed, how it works, and how often dialysis is typically done.

What is Fistula in Dialysis?

In the context of dialysis, a ‘fistula’ refers to an arteriovenous (AV) fistula. This term might seem complicated, but it’s simply the name for a connection created surgically between an artery and a vein in the body. This connection is crucial for those who require kidney dialysis as a part of their treatment for kidney disease or kidney failure.

A dialysis fistula is an essential part of this process. The fistula, created usually in the arm by a vascular surgeon, becomes an access point through which blood can be taken from the body, cleaned through the dialysis machine (essentially doing the work of the kidneys), and then returned to the body.

When creating a fistula, the vascular surgeon connects a vein to a nearby artery. This connection allows the higher-pressure blood from the artery to flow into the vein. Over time, this increased blood flow causes the vein to enlarge and thicken, a process known as maturation. The mature fistula can then accommodate the needles used during the dialysis procedure, and it provides a high-flow, long-lasting access point for kidney dialysis treatment.

The use of a fistula for kidney dialysis is generally preferred over other types of vascular access due to its longevity, lower infection rate, and lower tendency to clot. After the fistula has been created, it requires careful maintenance to ensure it remains functional for kidney dialysis for many years. Proper care can help avoid potential complications and ensure a smoother and more efficient dialysis procedure for those living with kidney disease or kidney failure.

Also Read: Why an AV fistula is Considered a Lifeline for Dialysis Patients?

Why is Fistula Needed for Dialysis?

A fistula is crucial for dialysis as it creates a durable and reusable access point for the procedure. During dialysis, blood must be transported from the patient’s body to the dialysis machine, where it is cleansed and then returned to the body. This process requires a robust and reliable access point that can tolerate repeated needle insertions. The fistula’s larger size and higher-pressure arterial blood flow allow for the high blood flow rates necessary for effective hemodialysis.

Furthermore, an AV fistula has a lower risk of complications such as clotting and infections compared to other dialysis access methods, making it the preferred choice for dialysis access whenever feasible.

How Dialysis Fistula Works?

A dialysis fistula works by providing a robust and efficient pathway for blood flow from the patient’s body to the dialysis machine and back.

After the creation of the fistula by a vascular surgeon, it requires a ‘maturation’ period, typically a few weeks to a few months. During this time, the connected vein, exposed to the higher pressure of the arterial blood flow, enlarges and strengthens. Once the fistula matures, it’s ready for use in dialysis.

During a dialysis procedure, two needles are inserted into the fistula. One draws blood to be filtered in the dialysis machine, and the other returns the cleaned blood to the patient’s body.

How Often Dialysis is Done?

What signs during or after dialysis should be of concern?

1. Poor flow
2. High venous pressures and excessive bleeding after dialysis
3. Difficult needling of dialysis fistula
4. Local Redness, swelling and pain, suggestive of infection or clotting.
5. Swelling of entire upper limb suggestive of central vein blockage.
6. Pain and reduced movements of fingers.

Also Read: 8 Tips to Improve Blood Circulation in Legs & Feet