CPT® Code 0494T

Surgical preparation and cannulation of marginal (extended) cadaver donor lung(s) to ex vivo organ perfusion system, including decannulation, separation from the perfusion system, and cold preservation of the allograft prior to implantation, when performed

Ex vivo lung perfusion (EVLP) is a specialized technique utilized in the preservation and assessment of cadaver donor lungs, particularly those sourced from high-risk donor pools. This method allows for the evaluation of lung viability outside the body before transplantation. The procedure involves a sophisticated circuit that includes a hard shell reservoir, a centrifugal pump, a leukocyte filter, and a hollow-fiber oxygenator, which is equipped with a gas and heat exchanger. The process begins with the standardized harvesting of the donor lungs, which are then perfused with a cold solution containing low molecular dextran, calcium chloride (CaCl2), tromethamine, and epoprostenol sodium. This solution is critical for maintaining the lungs' viability during the assessment phase. During the procedure, the main pulmonary artery and trachea are carefully dissected, and the left atrial cuff is trimmed and sutured to a cannula that incorporates a transducer for pressure monitoring. The main pulmonary artery is subsequently cannulated to facilitate perfusion. A flexible bronchoscopy is performed to inspect the airways, and a bronchoalveolar lavage is conducted to collect samples for gram staining and cultures, which are essential for assessing the presence of infection. An endotracheal tube is then inserted into the trachea and secured, allowing for controlled ventilation. The lungs are placed within a humidity and temperature-controlled EVLP dome, where they are connected to the EVLP system. An antegrade perfusion is initiated using a solution that includes THAM buffer, heparin, methylprednisolone, and antibiotics tailored to the donor and recipient's gram stain and culture results. The perfusion process is meticulously monitored, ensuring that the lungs are adequately oxygenated and warmed to mimic normal physiological conditions. Throughout the procedure, various parameters such as cardiac index, pulmonary artery pressure, and left atrial pressures are continuously assessed to determine lung function. Once the lungs reach a temperature of 32° C, ventilation through the endotracheal tube commences. A chest x-ray is performed to check for any complications such as atelectasis, consolidation, or pulmonary edema. If one lung is found to be non-viable during the EVLP process, the perfusion of the contralateral lung continues to assess its viability for transplantation. After the evaluation and warming phase, the lungs are decannulated, separated from the EVLP system, and placed into a cold storage unit, awaiting transplantation into the recipient.