Last week MedLearn Media published an article by Bryan Nordley titled “Defend Against IR Dialysis Circuit Denials: Expert Coding Tips to Promote Success in 2026.”
I encourage you, especially those performing CPT® coding for these encounters, to check it out. It was my inspiration for today’s coding report, through which I’d like to outline an answer to a critical question: what is the dialysis circuit, and how is an AV fistula different from an AV graft?
A dialysis circuit is simply surgically created access that allows the filtration of the kidneys via a dialysis machine. Dialysis filters the kidneys when the patient no longer has the kidney function needed to adequately filter the blood. This access can be accomplished by an AV (arteriovenous) fistula or an AV graft. In emergency situations, a vascular catheter can be used until an AV fistula or graft can be performed.
How is an AV fistula different from an AV graft? An AV fistula connects a native artery to a native vein. This is usually in the patient’s arm, and frequently done in a side-by-side manner. This means they take the side of the artery and attach it to the side of the vein (the end of the vein can also be attached to the side of the artery, and would still constitute an AV fistula). An AV graft, on the other hand, is performed using a synthetic piece of tubing, where one end is inserted into the side of an artery and the other end is inserted into the side of a vein.
The National Kidney Foundation (NKF), in their publication “Hemodialysis Access: What You Need to Know,” identifies some important pros and cons between the AV fistula and the AV graft. The NKF notes that the pros of using an AV fistula include that they last longer, they are not prone to infection, and they provide excellent blood flow once the fistula is ready for use. The organization also notes that AV fistulas are less likely to develop blood clots and become blocked, certainly a positive for those patients requiring dialysis. Finally, they note that the patient can take a shower with an AV fistula – that is, once the access has fully healed following surgery. Noted as a negative is the need for an AV fistula to mature between one to four months before it can be used. It also notes that needles are needed to connect an AV fistula to the dialysis machine.
An AV graft, like an AV fistula, provides excellent blood flow once it is ready for use. Also similarly, patients are able to shower with an AV graft once it has fully healed. The negatives of an AV graft include that it is more prone to infection than an AV fistula. It also lasts less time than an AV fistula. An AV graft needs at least two weeks before it can be used.
The NKF notes that clotting can also be a problem with AV grafts. This complication may need to be corrected with surgery or other treatment. Finally, like the AV fistula, needles are needed to connect the AV graft to the dialysis machine.
For our PCS coding, the root operation used for the creation of either an AV fistula or an AV graft would be Bypass. Remember, bypass procedures are coded by identifying the body part bypassed “from” and the body part bypassed “to.” The fourth-character body part specifies the body part bypassed from, while the qualifier specifies the body part bypassed to.
