Combined Donor Cardiectomy And Pneumonectomy

Prior to operative extraction of the lung block, a flexible fiberoptic bronchoscopic examinaton of the trachea, lobar, and segmental bronchi is performed. The airways are inspected for evidence of gastroesophageal aspiration including gross purulence, mucosal erythema, blood, foreign bodies, or gastric contents. Minor purulent endobronchial secretions that clear easily with bronchial lavage and are not associated with mucosal inflammation are not considered a contraindication to transplantation. Careful inspection of the endobronchial tree is performed looking for tumors and extrinsic compression of the airways.

The initial operative procedure for combined heart and lung retrieval is similar to that for isolated donor cardiectomy. The use of bone wax is discouraged to avoid embolization to the pulmonary microvasculature. The pleurae are opened widely to allow visual inspection and palpation of both lungs, lysis of minor pleural

Cardiectomy

Fig. 9.4. Placement of pulmonary artery catheter proximal to the confluence of the branch pulmonary arteries for combined heart and lung procurement. The pulmonary artery will be divided at the level of cannulation. (From Baumgartner WA, Reitz BA, Achuff SC. Heart and Heart-Lung Transplantation. Copyright 1990 Philadelphia W.B. Saunders co. Harcourt Brace Jovanovich, Inc. p.114, with modifications)

Fig. 9.4. Placement of pulmonary artery catheter proximal to the confluence of the branch pulmonary arteries for combined heart and lung procurement. The pulmonary artery will be divided at the level of cannulation. (From Baumgartner WA, Reitz BA, Achuff SC. Heart and Heart-Lung Transplantation. Copyright 1990 Philadelphia W.B. Saunders co. Harcourt Brace Jovanovich, Inc. p.114, with modifications)

adhesions, and release of the inferior pulmonary ligaments bilaterally. Careful systematic inspection of the visceral pleura is made for evidence of significant pulmonary contusion, consolidation, laceration, or hemorrhage. Atelectatic portions of the lung can be reexpanded by having the anesthesiologist hyperinflate the lungs.

The main pulmonary artery and lesser curvature of the aorta are dissected from each other. The main pulmonary artery is cannulated near its bifurcation (Fig 9.4). A competent pulmonic valve will allow equal pressurization of both branch pulmonary arteries, avoiding the need for clamping of the pulmonary artery. The right pulmonary artery is dissected free from the superior vena cava. The interatrial groove (Watterston's groove) is dissected to allow an adequate atrial cuff to be distributed between the donor heart and lung organ blocks. Thymectomy and division of the innominate vein (only if the CVP line enters from the right side) greatly improves exposure of the great vessels for later division.

After the other organ procurement teams have completed their preparations and systemic heparinization is achieved (3 mg/kg), 500 micrograms of prostaglandin El (Prostin VR) diluted in 30-50 ml of D5W is administered centrally over 60 seconds. This will cause acute pulmonary and systemic vasodilatation and hypotension and should not be given until all organs are ready for immediate perfusion and extraction.

Donor cardiectomy is initiated by ligating or clamping the superior vena cava and dividing the inferior vena cava. In contrast with the standard donor cardiectomy, the warm effluent from the inferior vena cava is not vented into the pleural

space to prevent uneven cooling of the lungs. A suction catheter is placed directly into the inferior vena cava to evacuate any blood or abdominal organ perfusate. The ascending aorta is cross clamped and 20 mL/kg of cold cardiac perfusate is delivered antegrade into the aortic root. The pulmonary perfusate (4-6 liters) is delivered simultaneously into the main pulmonary artery from an infusion bag which is elevated not more than 30 inches above the level of the chest. The tip of the left atrial appendage is amputated immediately to prevent pulmonary venous hypertension and left heart distension. The interatrial groove may also be incised to further vent the left heart and lungs. Topical cooling with an iced slush bath is performed and the lungs are visually inspected to ensure adequate blanching and uniform distribution of the perfusate. Ventilation is continued with 50%-100% oxygen delivered at a peak airway pressure of 20-25 cm H20. The lungs are removed while inflated to prevent atelectasis, while avoiding hyperinflation.

The donor cardiectomy is performed prior to removal of the lung block. The superior vena cava is divided above the azygous followed by division of the distal ascending aorta. The main pulmonary artery is transected through the pulmonary cannulation site at the level of the bifurcation. The cuff of left atrial tissue is left attached to the left pulmonary veins by incising the left atrium at a point midway between the left pulmonary veins and the coronary sinus while leaving the left atrial appendage with the heart. Similarly, a cuff of left atrial tissue is left attached to the right pulmonary veins by incising a portion of the dissected in-teratrial groove. The heart is then able to be removed from the mediastinum and prepared for transport.

The donor pneumonectomy is completed by exposing the trachea through the posterior pericardium behind the ascending aorta and above the right pulmonary artery. The trachea is dissected from the esophagus lying posteriorly taking care to avoid injury to the membranous trachea and bronchi. The endotracheal tube is partially withdrawn while maintaining gentle insufflation of the lungs. The distal trachea is occluded proximally with a TA-30 stapling device to prevent contamination of the mediastinum, and distally at a point 2-3 cm above the carina with the lungs inflated. The trachea is then divided between the staple lines. The nasogastric tube is removed and the upper thoracic esophagus is divided with a GIA stapler. Suprahilar attachments are divided followed by the inferior pericardium and inferior pulmonary ligaments. The lower thoracic esophagus is divided with a GIA stapler along with the distal thoracic aorta which are left attached to the lung block. After removal of the remaining posterior vertebral attachments, the combined lung block is removed to a back table and immersed into an iced saline bath. If both lungs are being procured for the same patient, they may simply be stored together for transport in nonrigid plastic bags filled with chilled lung perfusate, and placed on ice. If each lung is destined to separate recipients, the lung block is divided on the back table by division of the juxtacarinal left main bronchus, using a double application of a stapling device.

Blood Pressure Health

Blood Pressure Health

Your heart pumps blood throughout your body using a network of tubing called arteries and capillaries which return the blood back to your heart via your veins. Blood pressure is the force of the blood pushing against the walls of your arteries as your heart beats.Learn more...

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