A Rat Model of Orthotopic Liver Transplantation Using a Novel Magnetic Anastomosis Technique for Suprahepatic Vena Cava Reconstruction

The reconstruction of the suprahepatic vena cava (SHVC) remains a difficult step in rat orthotopic liver transplantation. In this article, we show a step-by-step protocol for SHVC reconstruction in rats using a novel magnetic anastomosis technique.

The overall goal of this protocol is to introduce a rat orthotopical liver transplantation model using a magnetic anastomosis technique for suprahepatic vena cava reconstruction. This method can help answer key question in the liver transplantation model about suprahepatic vena cava reconstruction. The main advantage of this technique is that it reduces the anhepatic phase of liver transplantation and greatly improves the postoperative survival rate.

First, shave the entire abdominal skin of the rat. Disinfect the corresponding skin with a povidone-iodine solution. Dissect the falciform ligament around the liver.

Next, isolate and ligate the left inferior phrenic vein. Perform a V incision on the anterior wall. Insert the stent into the lumen of the bile duct.

Make sure at least half of the stent lies outside the bile duct. Secure the stent with a 6-0 silk suture. Cut one end of the suture.

Keep the other one to hold during later anastomosis. Isolate the infrahepatic vena cava down to the left renal vein level. Dissect it until the infrahepatic vena cava is skeletonized.

Separate and ligate the right suprarenal vein. Separate and ligate the right renal vein. Heparinize the rat through the dorsal vein of the penis.

Insert a 22-gauge catheter into the abdominal aorta below the left renal vein. Perform a thoracotomy. Clamp the thoracic aorta using a microforceps.

Perfuse the donor liver through the catheter in the aorta. Transect the suprahepatic vena cava. In the meantime, cut the vena cava below the right renal veins to allow the perfusate flowing out of the liver.

Dissect the connective tissue surrounding the portal vein. Ligate and divide the pyloric vein. Transect the portal vein at the level of the splenic vein.

Transect the infrahepatic vena cava at the level of the left renal vein. Liver graft preparations are performed in four degree Celsius saline bath. Insert the infrahepatic vena cava into its cuff, with the cuff extension pointing towards to the liver.

Evert the distal end of the infrahepatic vena cava over the cuff body. Secure the edge with a 6-0 silk suture. Repeat the above steps on the portal vein to attach a cuff to the donor's portal vein.

Pull the diaphragm through the forceps, and trim the suprahepatic vena cava. Pass the suprahepatic vena cava through the magnetic ring. Evert the distal end of the suprahepatic vena cava over the ring.

And secure the ring with a 6-0 silk suture. Then, remove the excess diaphragm around the liver. Place a 6-0 silk suture, and ligate the common bile duct.

Isolate the common bile duct from the first hepatic portal. Ligate and divide the right adrenal vein. Place a strap in the suprahepatic vena cava of the liver.

Clamp the infrahepatic vena cava just above the right renal vein with microvessel clips. Clamp the portal vein at the level of pyloric vein. Inject two milliliter normal saline through the portal vein slowly to flush the blood out of the liver.

Drag down the liver by pulling the previous placed strap. Clamp the suprahepatic vena cava and part of the diaphragm with a Satinsky clamp. Excise the liver by transecting the suprahepatic vena cava just above the liver.

Transect the infrahepatic vena cava close to the parenchyma and the portal vein at the porta hepatis. Insert the recipient's remaining suprahepatic vena cava into a magnetic ring. Fix the magnetic ring on a Satinsky clamp by magnetic attraction.

Evert the suprahepatic vena cava over the magnetic ring. Place the donor liver graft orthotopically, and fill the lumen with normal saline solution, coupling the magnetic rings to fulfill the vessel construction. Reconstruct the portal vein.

Fill the lumen of the portal vein with normal saline. Insert the cuff body of the donor's portal vein into the recipient's portal vein. And secure that with a circumferential 6-0 silk ligature.

Remove the Satinsky clamp from the suprahepatic vena cava. Incise a V on the anterior wall of the common bile duct. Insert the donor stent into the lumen of the recipient bile duct.

And fix it with a 6-0 silk circumferential suture. Pull the sutures on the two bile ducts together, and tie the sutures to bring the bile ducts close to each other. The angiography two weeks POD showed a patent blood flow of the suprahepatic vena cava anastomosis.

The post-transplant survival rate was up to 85%to day 30 POD. The magnetic anastomosis technique makes easy and fast suprahepatic vena cava reconstruction in rats possible. After watching this video, without advanced microsurgical skills, can produce reliable and reproducible results using this rat model of liver transplantation.