Surgical Steps In Bilateral Lung Transplantation
A standard double lung transplantation includes a series of steps involving incision (median sternotomy or clamshell thoracotomy), cardiopulmonary bypass (CPB) in many cases, right and left pneumonectomies of the native lungs, preparation of the donor lungs, and implantation of the donor lungs. For the purposes of this post, I’ll talk about a bilateral lung transplantation with median sternotomy on CPB.
The anesthetic plan for lung transplants includes: general endotracheal anesthesia (+/- lung isolation), arterial line, central venous catheter, and intraoperative transesophageal echocardiography (TEE). Blood products are prepared ahead of time, and close communication is maintained with the surgical and perfusion teams at all times.
After sternotomy, the hilar structures are dissected. The pericardium is opened and exposure is maintained with standard pericardial sutures. Pursestring sutures are placed in the ascending aorta, right atrial appendage, and superior vena cava (SVC) with subsequent bicaval venous cannulation and ascending aorta cannulation after appropriate systemic heparinization. Vents are commonly placed in the main pulmonary artery (PA) and ascending aorta to capture air and maintain a “bloodless” field. After initiating bypass, adhesiolysis and hilar dissection is completed while the donor lungs are prepared.
Explantation of the native lungs is performed by using a vascular staple to transect the pulmonary vessels (superior pulmonary vein, pulmonary artery, and inferior pulmonary vein) with sharp transection of the bronchus of each lung. The donor lungs are implanted beginning with the bronchial anastomosis (4-0 Prolene SH-1), followed by attaching the pulmonary veins to the recipient’s left atrium (4-0 Prolene SH-1) and finally the pulmonary artery anastomosis with 5-0 RB-1 Prolene suture. The PA vent is stopped and low pressure reperfusion of the transplanted lung is permitted with subsequent air liberation from the pulmonary vein anastomosis. A left atrial (LA) vent is often placed across the suture line. The same procedure is performed for each lung. Bronchoscopy is utilized to visualize the bronchial anastomoses of the new lungs. After ventilating the lungs for 10-15 minutes and performing low pressure perfusion, the patient is rewarmed, weaned from CPB and the LA vent is removed after securing the suture line and confirming very little to no air remaining in the LA using TEE.
Protamine is administered with careful surgical hemostasis and removal of the CPB cannulas. TEE is utilized to confirm normal pulmonary vein flows and ventricular function post procedure. Typically five chest drains are placed – the lateral tubes basilar, medial tubes apical and anterior, and the fifth tube in the mediastinum. Stainless steel wires are used to close the sternum and the overlying soft tissue is closed in layers with absorbable suture.