CPT® Code 0494T

1. Indications

The procedure of ex vivo lung perfusion (EVLP) is indicated for the assessment and preservation of cadaver donor lungs, particularly those obtained from high-risk donor pools. The following conditions warrant the use of EVLP:

• High-Risk Donor Lungs Lungs from donors who may have compromised function or are otherwise considered unsuitable for immediate transplantation.
• Assessment of Lung Viability To evaluate the functional status of the lungs prior to transplantation, ensuring that only viable organs are used.
• Preservation of Donor Organs To maintain the integrity and function of the lungs during the period between harvesting and transplantation.

2. Procedure

The procedure for ex vivo lung perfusion (EVLP) involves several critical steps to ensure the successful assessment and preservation of donor lungs:

• Step 1: Surgical Preparation The procedure begins with the surgical preparation of the cadaver donor lungs, which includes the careful dissection of the main pulmonary artery and trachea. The left atrial cuff is trimmed to facilitate anastomosis with a cannula that contains an integrated transducer tool for pressure monitoring.
• Step 2: Cannulation The main pulmonary artery is cannulated to allow for the perfusion of the lungs. This step is crucial for establishing a connection to the EVLP system.
• Step 3: Bronchoscopy and Lavage A flexible bronchoscopy is performed to evaluate the airways, followed by a bronchoalveolar lavage to obtain samples for gram staining and cultures, which are essential for assessing potential infections.
• Step 4: Endotracheal Tube Insertion An endotracheal tube is inserted into the trachea and secured with sutures or ties, allowing for controlled ventilation during the perfusion process.
• Step 5: Placement in EVLP Dome The lungs are placed into a humidity and temperature-controlled EVLP dome, which is designed to maintain optimal conditions for the organs during the assessment.
• Step 6: Connection to EVLP System The pulmonary cannula is connected to the EVLP system, and antegrade perfusion of the lungs 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.
• Step 7: Monitoring and Ventilation The lungs are monitored for various parameters, including cardiac index, pulmonary artery pressure, and left atrial pressures. Ventilation through the endotracheal tube begins once the lungs reach a temperature of 32° C.
• Step 8: Imaging and Evaluation A chest x-ray is obtained to evaluate for complications such as atelectasis, consolidation, or pulmonary edema. If one lung is found to be non-viable, perfusion of the contralateral lung continues to assess its viability.
• Step 9: Decannulation and Cold Storage Following the assessment, the lungs are decannulated and separated from the EVLP system. A final chest x-ray is performed, and the lungs are then placed into a cold storage unit until the recipient is prepared for transplantation.

3. Post-Procedure

After the completion of the ex vivo lung perfusion (EVLP) procedure, several post-procedure considerations are essential. The lungs are carefully monitored for any signs of complications, and a chest x-ray is performed to ensure that there are no issues such as atelectasis or pulmonary edema. The lungs are then placed into a cold storage unit, where they are preserved until the recipient is ready for transplantation. It is crucial to maintain the appropriate storage conditions to ensure the viability of the lungs for successful transplantation. The timing of the transplant is critical, as the preservation period must be managed to optimize outcomes for the recipient.