Coding Arteriovenous FistulaProcedures Can Be Tricky
Peggy Hapner, RRA, CCS
Arteriovenous (AV) fistula procedures can be difficult to understand let alone to assign CPT procedure codes. When an AV graft is created in a patient, the patient often must return to the operating room for declotting, dekinking and/or thrombectomy of the graft. Depending upon the procedure performed, there are several coding options available to be assigned. The following case scenarios will describe a few of the codes available and which code should be used.
Postoperative Diagnosis: Clotted right forearm AV graft
Procedure: Graft thrombectomy, right forearm arteriovenous graft
With the patient in the supine position on the operating table, having received adequate IV sedation, the right arm, axilla and shoulder were sterilely prepped and draped. The old vertical distal upper arm incision was reopened over the Gore-Tex graft. The graft was dissected free of the surrounding tissues over a 3-cm length. The graft was opened transversely and found to be filled with clot.
A #3 Fogarty catheter was passed proximally some 40 cm without meeting any resistance and withdrawn. Propagated clot came with it. After several passes, there was fairly brisk venous back bleeding. The venous limb was flushed with heparinized saline and clamped. A #3 Fogarty was then passed down the arterial limb. The catheter passed without resistance to 50 cm. At 50 cm, there was transient resistance to the #3 Fogarty, but eventually it could be passed its entire length. Multiple passes were made, and a great deal of propagated clot was withdrawn, eventually establishing what I consider fair pulsatile inflow, with no further clot being retrieved.
A #4 Fogarty catheter was then utilized. The catheter could only intermittently be passed its length into the arterial inflow. It was withdrawn without clot. Pulsatile flow remained somewhat tepid. There was some narrowing at the arterial anastomosis. The graft was then closed with running #5-0 Prolene. When the vascular clamps were removed, there was an audible bruit in the medial aspect of the upper arm, as well as good Doppler flow through the graft and through the vein, exiting the graft.
Code assignment: 35875, Thrombectomy of arterial or venous graft
Rationale: The physician used Fogarty catheters and passed the caths through the arteriovenous graft several times and removed some clots. In the last pass through the graft, no clots were returned. The physician did not revise the graft at any time.
Postoperative diagnosis: Thrombosed AV access graft, left arm, end stage renal disease
Procedure: Thrombectomy, revision of AV graft, left arm
The patient was placed on the OR table in the supine position. After establishing adequate IV sedation, the patient was prepped and draped in the usual sterile manner. The skin at the graft to venous anastomosis was then infiltrated with local anesthesia and a skin incision was made by blunt and sharp dissection. The venous anastomosis was identified and vessiloops were passed around the vein and grasped for proximal and distal control. The graft was then opened across the venous anastomisis.
There was obvious significant hyperplasia at the venous anastomosis, and this was carefully removed by applying forceps. The graft was thrombectomized with a Fogarty catheter. It appeared as though the entire thrombus was removed from the arterial end, and digital pressure was applied. The graft was thrombectomized several times with a #4 Fogarty catheter and flushed with heparinized saline solution and clamped just proximal to the opening of the graft. The Fogarty catheter was then used to thrombectomize the vein. The vein was opened a short distance proximal to the anastomosis. This venotomy and opening in the patch obtained from a 7-mm Gore-Tex graft. This was done with a continuous suture of #6-0 Prolene.
Following this, the clamps were re-moved, and there was an excellent continuous thrill established in the graft and in the vein proximal to the anastomosis. The wound was packed with thrombin-soaked Gelform, and hemostasis was allowed to occur. The deeper layers were approximated with interrupted sutures of #3-0 Dexon, and the skin was closed with a continuous suture of #4-0 Prolene. The wound was dressed with a sterile dressing. The patient tolerated the procedure well and left in stable condition.
Code Assignment: 36832, Revision of an arteriovenous fistula, with or without thrombectomy, autogenous or non-autogenous, graft (separate procedure)
Rationale: The AV graft was revised (open and cleaned out), not just declotted. The main emphasis belongs on the required revision for this code assignment.
Other Coding Options
In addition to the above case studies, there are other possible code assignments for declotting of an AV fistula.
* If the clot in the fistula is removed by mechanical means (i.e., balloon catheter), assign CPT code 36861–cannula declotting; with balloon catheter.
* If the physician chooses to use high-pressure pulsed normal saline hydromechanical lysis, then assign CPT code 36860–cannula declotting, without balloon catheter.
* If a thrombolytic agent (urokinase or streptokinase) is administered by intravenous infusion, assign CPT code 37201–transcatheter therapy, infusion other than for thrombolysis, any type.
Peggy M. Hapner is a senior health care consultant and outpatient coding expert at Medical Learning Inc. (MedLearn), St. Paul, MN.