Creation of reversible cholestatic rat model. Hello everyone. I'm Goulash General Surgery resident from Providence Hospital and Medical Centers in Southfield, Michigan.
Today I will demonstrate the creation of a reversible cholestatic rat model set up. The rat is anesthetized using isof fluorine in the chamber and later on with a mask During the procedure, a polyester tube with the outer diameter of 0.9 millimeter and inner diameter of 0.6 millimeter is used with one end be well and other end sealed instruments used include a standard rat pack microsurgical instruments, ophthalmic spears Q-tips Eight oh nylon. The procedure is Performed using operating microscope.
It can alternatively be performed using Surgical loops. A steady drape is being applied here. This procedure is performed under all sterile precautions.
Operative steps at two centimeter midline incision is placed starting from the zip sternum. The subcutaneous tissue and fascia is being cut open using scissors. The peritoneum is being cut open here exposing the liver.
Hemostasis ensure using a handheld cautery. This is the median and the left lobe of the liver Rat biliary anatomy. This is a schematic diagram of rat biliary anatomy.
The rat liver is divided into the right median left and chordate lobes. This is the nu and the stomach and this is the bile duct. Here you see that a significant portion of the bile duct is not associated with the portal vein and hepatic artery.
It is this portion of bile duct, which is used for hooking and creation of cholestasis. The liver lobes are retracted using send retractor and Q-tip is used to pull the num down. The bile duct is then hooked using a microsurgical instrument close to theum.
This is the same step of hooking the bile duct, which is being demonstrated in in a different rat model. And again, this is the same step of hooking the bile duct, which has been recorded from outside the operating microscope. Cholestasis creation, a file polys sub suture is then passed beneath the bile duct and the bile duct is put under traction.
This is the bile duct under traction. This is a zoom in view. The bile duct is being cut open here.
The peoplel edge of the poly tube is then passed into this bile duct. We use a tube feeder microsurgical instrument to help us in this process. Care has to be taken that the tube is pushed in gently.
A window is then made in the proximal bile duct. Eight nylon suture is then passed in this window. The ATO suture is then tied off using three square knots to hold the tube in place.
A second window is created beneath the Blac proximal to the first suture. Another ATO suture is used to secure the tube proximally. A window is then made in the distal part of the bile duct and ATO suture is passed through it.
This is used initially to tie off the bile duct. This suture is then wrapped around the tube and tied around the tube, thus anchoring the tube securely. The suture is being cut Here, the traction suture is then pulled out.
Here we are zooming out again. The tube is then pushed back into the peritoneal cavity and is made to lie comfortably. The abdomen is then washed using two ml of normal saline.
The fluid is then drained off using a two by two gauze. A final look is then taken to confirm the correct comfortable lie of the tube and for hemostasis abdomen closure. The fascia is being closed with five oh poly actin continuous suture.
The skin is then closed with dermal interrupted sutures. Cholestasis reversal cholestasis is reversed by training the polyester cube into the odum cholestasis Reversal is being demonstrated in the rat in the same setting.Here. The skin and the fascia is being cut open with scissors.
The liver is retracted and the deum is being pulled on. With the Q-tips, we identify a spot in the deum for comfortable lay of the polyester tube. We then lay bursting sutures with eight or nylon around the site preselected for placement of the tube.
We ensure that serum muscular bites are taken during each stitch. NEP poly tube is then pulled out from the peritoneal cavity. In cases where the tube has been left for a longer time, there be significant or mental audation around the tube, which has to be gently freed up.
The tube is then cut with the scissors over a swab to soak the bile drainage. In cases where the tube has been left for longer duration, we see significant amount of bile pouring out. When the tube is cut open, the durum is then cut open at the center of the pulse string suture with a scissor ensuring that all thickness of the durum has been cut open.
The tube is then pushed into the nu and we ensure that it lays comfortably and it's aligned in the right direction. The post stringing suture is then tighten with the three squire knots to anchor the tube in the dynam. The wound is then irrigated to clear up the bile, which would've leak during the procedure, and the ADOS then closed the ensure that the tube is laying comfortably and there's good hemostasis before closure.
Demonstration of biliary drainage here, just for demonstration purposes, we are pulling the tube out from the Jordan to demonstrate that there's free drainage of bile from the tube Application Of this model, application of this model. This model can be used in studying the physiological pathological and histological changes in the biliary system and gastrointestinal tract associated with cholestasis. This model can be used to study the effects of cholestasis on liver surgery and it can also be used to study the changes in the nutritional status associated with cholestasis.