Establishment Of Canine Portal Vein Thrombosis Model

Objective: Through the method of "portal vein catheterization implanted subcutaneously plus autologous thrombus injection plus thrombin injection",to establish a canine portal vein thrombosis model and to provide a selectable large animal thrombus model for diagnosis and treatment of portal vein thrombosis diseases.Methods: Ten adult hybrid dogs(from 16 to 20Kg)were adopted.The median abdominal incision was taken to find the superior posterior duodenum vein of portal vein branch.Above the superior posterior duodenum vein,which was a branch of portal vein,a catheter was inserted into the portal vein trunk.After catheterization,portal vein antegrade angiography was performed and portal vein pressure was measured as a control.A 10 ml syringe was used at the tail end of the catheter to draw 3ml,3ml and 10 ml of blood successively into the blood collection vessel.They were used to detect fibrinogen,D dimer and to prepare autologous thrombus respectively.Thrombin injection 10 ml plus autologous thrombus 4ml were injected into the catheter.The catheter was ligated and fixed with silk thread at the puncture site.And the catheter was detained subcutaneously as a venography pathway.The general conditions(appetite,mental state)of dogs before and after operation were observed.At 30 min,12h,24 h,48h,72 h after modeling,portal vein pressure value was measured by catheter retained in the portal vein and blood was drawn to detect changes in coagulation function and D-dimer index.At the same time,at 30 min,12h,24 h,48h,72 h after modeling,the patency of the portal vein and its branches was understood by antegrade venography through the catheter retained in the portal vein.72 h after the modeling,the dogs after successful modeling were executed.Thrombus segment of portal vein was dissected for pathological analysis.Result: In the ten dogs,seven dogs were successfully modeled.The success rate of the model was seventy percent.After successful modeling,the animal dogs suffered from poor mental state,decreased appetite and other situations.D-dimer test in dogs: the results of 30 min,12h,24 h,48h and 72 h after operation were higher than those before operation(p<0.05).The results of 72 h after operation were significantly higher than those of 30 min,12h,24 h and 48 h after operation(p<0.05).Fibrinogen of dogs: the results of 30 min,12h,24 h,48h and 72 h were higher than those before operation(p<0.05).And the results of 72 h after operation were significantly higher than those of 30 min,12h,24 h and 48 h after operation(p<0.05).Portal vein pressure value of dogs: the results of 30 min,12h,24 h,48h and 72 h after operation were higher than those before operation(p<0.05).The results of 72 h after operation were significantly higher than those of 30 min,12h,24 h and 48 h after operation(p<0.05).30 min after modeling,anterograde venography was performed,showing portal vein trunk filling defect,which indicated that portal vein thrombosis formed and the volume of filling defect gradually increased with the increase of time,which indicated that portal vein thrombosis became more and more obvious with the increase of time.HE staining of portal vein specimens 72 hours after operation: Thrombosis was obviously visible in portal vein lumen,thrombus adhered to the wall of the tube and was not easy to separate.And the boundary was not clear.Thrombosis was filled with a large amount of fibrin and platelet trabeculae.A large number of red blood cells could be seen in the mesh formed by fibrin.Conclusion:1.Animal dogs canine portal vein thrombosis model can be successfully constructed by the method of " portal vein catheterization implanted subcutaneously plus autologous thrombus injection plus thrombin injection".2.This model has the characteristics of stability,fast forming,high forming rate and easy operation.3.In this model,the subcutaneously implanted portal vein catheter has the functions of repeatable angiography,blood sampling,pressure measurement and drug delivery channel.