Case Study: Cardiovascular System Procedure

Vol. 12 •Issue 4 • Page 8
Coding Corner

Case Study: Cardiovascular System Procedure

Preoperative Diagnosis: Thrombosis of right forearm; loop Gore-Tex hemodialysis fistula with no mechanical problem identified.

Postoperative Diagnosis: Thrombosis of right forearm; loop Gore-Tex hemodialysis fistula with no mechanical problem identified.

Procedure Performed: Thrombectomy of right forearm graft.

Anesthesia: Right axillary block.

Extremities: Symmetrical without edema. In the right upper extremity, there is a looped Gore-Tex subcutaneous graft (right forearm) with no palpable pulse, thrill or audible bruit. There is no evidence of erythema, edema or tenderness in the arm.

Operative Findings: The patient had thrombus in the loop Gore-Tex fistula in the right forearm. This is actually the third such loop fistula placed in the concentric fashion. It is the outer most of the three fistulas, and the only one currently functioning. The other two are disconnected.

The patient had calcification in the distal 4-5 cm of the venous limb of the graft; however, there was no narrowing greater than 50 percent noted on the fistulogram. The fistulogram showed adequate arterial end flow with good arterial vessels coming from the brachial artery and through its bifurcation into the forearm. There was a widely patent graft and good venous outflow into the cephalic vein in the arm. There was no evidence of stenosis in the vein in the antecubital fossa. The median cubital vein remained widely patent as it has always been with no evidence of venous outflow stenosis in the vein.

Operative Technique: After induction of a right axillary block without complications, the right upper extremity was prepped with Duraprep solution and draped using sterile towels and sheets.

A 4-cm transverse incision was made with an existing transverse scar in the antecubital fossa. The underlying arterial and venous limbs of the graft were dissected free from surrounding structures, and the patient was given 5,000 units of Heparin IV.

A graftotomy was made transversely in the distal venous limb of the graft and in the first centimeter of the arterial end of the graft. Thrombectomy was accomplished with 3 and 4 Fogarty catheters with brisk arterial end flow and good venous back-bleeding noted. The graftotomy sites were closed using a 5-0 Prolene running suture and a 19-gauge butterfly placed in the venous end of the graft. Venous- and arterial-phase fistulograms were performed using a total of 40 cc of hypaque solution. The arteriograms were read as above.

The butterfly was removed, and the patient was given 30 mg Protamine to reverse the 5,000 units of Heparin given prior to thrombectomy. The subcutaneous tissue was approximated using a 3-0 Vicryl running suture, and the skin edges approximated using 4-0 Prolene running simple skin sutures.

Sponge, needle and instrument counts were reportedly correct. The patient was taken to the recovery room in satisfactory condition.

Coding Rationale

Diagnosis Codes: The preoperative and postoperative diagnoses were the same (i.e., thrombosis of right forearm loop; Gore-Tex hemodialysis fistula with no mechanical problem identified). The same ICD-9-CM code is assigned for both diagnoses.

996.73 Other complication due to renal dialysis device, implant and graft

CPT Codes:

The surgeon states that an incision was made in both limbs of the graft. The clot was removed using Fogarty catheters until brisk flow was returned in both ends of the graft. The incisions were then closed.

Look in the CPT manual index under the terms Thrombectomy, Dialysis Graft and without Revision. The code listed there is 36831, which is the correct choice for both the facility and professional claims. No modifier is required for this procedure.

36831 Thrombectomy, open, arteriovenous fistula without revision, autogenous or non-autogenous dialysis graft

Dawn Seelye is a senior health care consultant for Medical Learning Inc. (MedLearn®), St. Paul, MN.