CPT® Code 36835

1. Indications

The insertion of a Thomas shunt is indicated for patients requiring long-term access to the vascular system for hemodialysis. This procedure is typically performed in individuals who have compromised vascular access due to previous dialysis treatments or other medical conditions that affect the veins and arteries. The Thomas shunt provides a reliable means of accessing the bloodstream, which is essential for effective hemodialysis therapy.

• Long-term Hemodialysis Access Patients who need repeated access to the vascular system for hemodialysis due to chronic kidney disease or renal failure.
• Compromised Vascular Access Individuals with previous vascular access failures or those who have developed complications from other access methods.

2. Procedure

The procedure for inserting a Thomas shunt involves several critical steps to ensure proper placement and functionality of the device. First, the surgeon prepares the patient and marks the incision sites over the femoral artery and vein. This is followed by the administration of local anesthesia to minimize discomfort during the procedure.

• Step 1: Incision and Exposure Small incisions are made over the femoral artery and vein to expose these blood vessels. The surgeon carefully dissects the surrounding tissue to gain access to the vessels without causing damage.
• Step 2: Vessel Incision Once the vessels are adequately exposed, the surgeon incises the femoral artery and vein. This step is crucial as it allows for the insertion of the silastic cannulas.
• Step 3: Cannula Placement The Dacron patch at the end of one silastic cannula is sutured to the femoral artery, while the other silastic cannula is sutured to the femoral vein using the Dacron patch. This technique helps to secure the cannulas in place and prevents occlusion of the vessels.
• Step 4: Tunneling The two cannulas are then tunneled subcutaneously to the anterointernal aspect of the thigh, exiting through two separate skin incisions. This tunneling minimizes the risk of infection and provides a discreet access point for dialysis.
• Step 5: Connector Assembly The tips of the two external cannulas are joined with a Teflon connector, forming a closed loop. This connector is designed to be easily removed during dialysis procedures, allowing for quick and efficient access to the vascular system.
• Step 6: Post-Procedure Connection During hemodialysis, the Teflon connector is removed, and the cannulas are connected to the hemodialysis tubing. After the dialysis session, the Teflon connector is replaced on the silastic cannulas to maintain the closed system when not in use.

3. Post-Procedure

After the insertion of the Thomas shunt, patients are typically monitored for any immediate complications, such as bleeding or infection at the incision sites. Post-procedure care includes keeping the incisions clean and dry, as well as following any specific instructions provided by the healthcare team regarding activity restrictions and signs of potential complications. Patients may be advised to avoid heavy lifting or strenuous activities for a period of time to ensure proper healing. Regular follow-up appointments are essential to assess the functionality of the shunt and to address any issues that may arise during its use for hemodialysis.