CPT® Code 33766

1. Indications

The classical Glenn procedure (CPT® Code 33766) is indicated for patients experiencing cyanosis due to congenital heart defects. The following conditions may warrant this procedure:

• Tetralogy of Fallot A congenital heart defect characterized by four specific heart abnormalities that result in insufficient oxygenated blood reaching the body.
• Other Cardiac Anomalies Various congenital heart defects that lead to inadequate blood flow and oxygenation, necessitating surgical intervention to alleviate symptoms of cyanosis.

2. Procedure

The classical Glenn procedure involves several critical steps to establish a shunt from the superior vena cava to the right pulmonary artery:

• Step 1: Access and Preparation The procedure begins with a median sternotomy, which allows the surgeon to access the heart and surrounding structures. Cardiopulmonary bypass is then initiated to ensure that blood circulation and oxygenation are maintained during the surgery.
• Step 2: Transection of the Right Pulmonary Artery The right pulmonary artery is carefully transected to prepare for the anastomosis with the superior vena cava. This step is crucial for redirecting blood flow.
• Step 3: Anastomosis Creation An end-to-side anastomosis is performed by connecting the transected right pulmonary artery to the superior vena cava. This allows deoxygenated blood from the superior vena cava to flow directly into the right pulmonary artery.
• Step 4: Ligation of Azygos and Hemiazygos Veins The azygos and hemiazygos veins are ligated to prevent any backflow and to ensure proper blood flow through the newly created shunt.
• Step 5: Clamping and Transection of the Superior Vena Cava The superior vena cava is clamped and transected between the clamps. The cardiac end is then sutured in two layers to secure the connection.
• Step 6: Finalizing the Anastomosis The right pulmonary artery is incised longitudinally, and the superior vena cava is anastomosed in an end-to-side fashion to the right pulmonary artery. This completes the shunt creation.
• Step 7: Weaning Off Cardiopulmonary Bypass Once the anastomosis is complete, the clamps are released, and the patient is gradually weaned off cardiopulmonary bypass. This step is critical for restoring normal blood flow.
• Step 8: Closure Chest tubes are placed as needed to drain any excess fluid, and the chest incision is closed to complete the procedure.

3. Post-Procedure

After the classical Glenn procedure, patients typically require close monitoring in a postoperative setting. Expected recovery includes observation for any complications related to the surgery, such as bleeding or infection. The placement of chest tubes may be necessary to manage fluid accumulation in the chest cavity. Patients may experience a gradual improvement in oxygenation levels as the body adjusts to the new blood flow dynamics. Follow-up care is essential to assess the effectiveness of the shunt and to plan for any further interventions that may be required for the underlying cardiac condition.