placed in the main pulmonary artery immediately proximal to its bifurcation. Occasionally the inter-atrial groove must be developed to increase the size of left atrial cuff on the right pulmonary veins. Lung procurement proceeds as follows:

1. A bolus injection of prostaglandin E1 (500 ^g) is administered directly into the main pulmonary artery alongside the cannula;

2. Double ligation of the SVC and clamping of the IVC at the diaphragm achieve inflow occlusion;

3. Cross-clamping of the ascending aorta and administration of cardioplegic solution;

4. Venting of the right heart (cardioplegic solution is vented through the IVC by transecting the IVC above the clamp; this necessitates a prior request to the abdominal procurement team to cannulate the abdominal segment of the IVC, so that their effluent flush can drain off the table);

5. Pulmonary flush is initiated: with the lungs continuously ventilated, pulmonary artery flushing is achieved with 50 ml/kg of modified Euro-Collins solution delivered at a pressure of 30 cmH20. Alternative preservation solutions include Perfadex and UW solutions.

6. Venting the left heart by amputating the tip of the left atrial appendage allows drainage of the pulmonary flush into both pleural spaces

7. Topical lung hypothermia is supplemented saline slush and ice.

8. The lungs are gently ventilated throughout to prevent atelectasis.

After completion of cardioplegia administration and lung flush, the heart is extracted first. The SVC is divided between the previously placed ligatures. The aorta is divided distal to the cardioplegia cannula. The main pulmonary artery is divided through the cannulation site, typically just proximal to the bifurcation. The heart is then elevated and retracted to the right. The left atrium is opened midway between the coronary sinus and inferior pulmonary veins. The left atrial incision is then continued toward the right. The right side of the left atrial wall is then divided, taking care to preserve a rim of atrial muscle on the pulmonary vein side. This completes the cardiac excision.

The lungs are extracted en block by:

1. Digitally encircling the trachea and dividing it between two applications of the TA-30 stapling device well above the carina keeping the lungs moderately inflated;

2. Division of the great vessels at the apex of the chest

3. Division of the esophagus superiorly and inferiorly by sequential application of the GIA stapler; and

4. Transection of the descending thoracic aorta at the level of the diaphragm.

The lung allografts are then immersed in cold crystalloid solution in the semi-inflated state. If the two lungs are to be used at separate centers, they can be divided at the donor hospital. This is done by dividing the posterior pericardium, the middle of the left atrium separating the pulmonary vein cuffs, transecting the pulmonary artery at its bifurcation, dividing the residual mediastinal tissue, and finally dividing the left main bronchus at its origin with a cutting stapling device. The double lung block or two separate lungs are then triple-bagged and transported in an ice chest (at 0-1°C).

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