Orthotopic Porcine Kidney Transplantation: A Technique to Transplant Graft Kidney in Porcine Model

Orthotopic kidney autotransplantation is a surgical procedure of transplanting a healthy kidney graft from the same donor at the original anatomical location in the organism's body.

To perform this procedure, take an anesthetized pig with its left kidney removed previously. Place it in the supine position. Make a midline incision exposing the abdominal cavity. Visualize the right kidney and the connected right ureter. Additionally, locate the oxygenated blood-carrying abdominal aorta, which branches to the renal artery. Similarly, the renal vein drains deoxygenated blood from the kidney into the inferior vena cava.

Clamp the ureter and renal vessels. Administer a vasoconstrictor - a chemical that constricts the vessels, reducing the blood flowing through them to prevent excess blood loss in the subsequent steps.

Perform the right kidney nephrectomy - kidney removal from the body. Replace it with the pre-isolated healthy kidney graft from the same pig. Anastomose the renal artery of the graft kidney to the aorta and the renal vein to the inferior vena cava. Unclamp the renal vessels and ureter and apply a vasodilator. These steps help to re-initiate blood flow in the grafted kidney.

Inject a diuretic solution into the kidney that aids urine formation to maintain blood pressure. Suture the abdominal cavity. Use Doppler ultrasound to monitor blood flow in kidneys. A successfully transplanted kidney shows normal blood flow in the renal vessels.

Two to five minutes before vascular clamping, intravenously inject 100 units per kilogram (100 I.U./ kg) of natrium-heparin, and subsequently, remove the contralateral right kidney, as demonstrated. Place the preserved graft kidney into the surgical field, and initiate the administration of 0.1 to 1 microgram per kilogram, per minute (0.1 to 1 µg/kg/min) of norepinephrine as continuous infusion, using the mean arterial blood pressure and heart rate to monitor the efficiency.

For end-to-end anastomosis of the renal vein, use 5-0 polypropylene to place two corner stitches, and suture the back wall in a continuous fashion. After completing the back wall, use one end of the cranial corner stitch to suture the front wall in a cranial-caudal direction, and flush the vein with a 100 international unit per milliliter (100 I.U./mL) of heparinized saline solution. For end-to-end anastomosis of the renal artery, use a 6-0 polypropylene cranial corner stitch, before using the parachute technique to search through the back wall in a continuous fashion, as demonstrated.

Suture the front wall with the other end of the double-armed 6-0 polypropylene suture, and flush the artery with 100 international units per milliliter (100 I.U./mL) of heparinized saline solution. After anastomosis completion, tie the two threads at the caudal corner, and sequentially open the venous vascular and arterial clamps to allow reperfusion of the kidney. Following reperfusion, topically administer 5 milliliters of papaverine to the outside wall of the renal artery, and intravenously administer 250 milliliters of 20% glucose solution in a single 80 milligrams dose of furosemide.

Next, pass a 12-French pediatric urine catheter through the abdominal wall and skin, and use ligatures to secure the catheter to the ureter. Close the peritoneal layer over the kidney, to prevent dislocation of the graph and kinking of the vascular anastomosis, and close the abdomen in four layers as demonstrated.

Finally, use color Doppler ultrasound to ensure adequate arterial and venous perfusion of the kidney graft before returning the fully recumbent animal to the housing facility.