This article details the surgical procedure for porcine heart extraction, emphasizing the steps taken to ensure the organ is preserved for further study. It outlines the techniques used to minimize blood loss and maintain physiological conditions during the extraction process.
For porcine heart extraction, place an anesthetized pig on a surgery platform in a supine position. Shave the chest region and sterilize it. Using a cautery pen, make a midline incision on the chest and open the chest wall to reveal the sternum.
Now, incise the sternum along its midline. Retract the sternum to reveal the pericardium - a fibrous sac enclosing the heart. Next, cut the pericardium and retract it to visualize the heart. Now, deliver heparin to avoid blood clotting. Then, place an IV catheter into the ascending aorta. Begin collecting blood through the catheter in an external reservoir bag. This drains the blood from the organ, a process called exsanguination.
Now, clamp the ascending aorta and superior vena cava to restrict the blood flow. Then, deliver an isotonic electrolyte solution into the aortic root. This solution gradually slows the cardiac activity, bringing the organ to rest and protecting it during storage.
To separate the heart from the adjoining blood vessels, transect the aorta and the pulmonary artery. Further, dissect the superior and inferior venae cavae and incise the pulmonary veins. Finally, excise the heart from the pig and preserve it under physiological conditions.
After confirming a lack of response to noxious stimulus, perform a median sternotomy on the anesthetized pig, and once the heart has been exposed, use Metzenbaum scissors to open the pericardium.
Use 1-0 silk sutures to fix the pericardial edges to the sternum, and gradually collect 750 milliliters of whole blood from the two-stage venous cannula, placed in the right atrium in an autoclaved glass container over a period of 15 minutes, while simultaneously replacing the volume with 1 liter of an isotonic crystalloid solution.
Add the blood to a perfusion circuit primed with 750 milliliters of Krebs-Henseleit buffer supplemented with 8% albumin, and place a 14-gauge cardioplegia needle and cannula into the ascending aorta. Secure the cardioplegia needle on the aorta with a snare, and connect the cardioplegia cannula to the cardioplegia bag.
Add 100 milliliters of blood to 400 milliliters of cardioplegia. After the end of exsanguination, cross-clamp the ascending aorta with an aortic clamp. Next, deliver the cardioplegic solution into the aortic root.
When all of the solution has been administered, remove the clamp and excise the heart, including all of the aortic arch vessels and a segment of the descending aorta.
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