Vena Cava Filter Implantation And Its Effect Research In Goats

Objective:In order to provide theoretical basis for veterinary clinical use and related research of vena cava filter(VCF),we explored the implantation method and clinic effect of VCF guided by ultrasound in goat.Methods:Twelve healthy goats weighing 41.52±4.56 kg were randomly divided into two groups.The experimental group,one side of jugular vein puncture was performed and the vena cava filter was implanted by the guidance of ultrasound.In the control group,the same side of jugular vein puncture was performed without vena cava filter.After the filter was implanted,ultrasonography and X-ray were used to observe whether the filter was fully deployed and shifted.The 12th days after operation,autologous thrombus was injected and the filter was removed the 14th days after operation for observed the catch of thrombus by the filter.The animals were sacrificed for tissue dissection and the veins of the filter implantation site were fixed,the pathological sections were stained with HE.The intimal hyperplasia thickness and inflammatory cell infiltration of veins in the two groups were compared.Routine blood test and blood coagulation tests were carried out from cephalic vein at the 1st day before operation,and the 1-7 days after operation.The dection parameters were as follows:total white blood cell count(WBC),lymphocyte count(LYM),central granulocyte count(GRAN),activated partial thromboplastin time(APTT),thrombin time(TT),prothrombin time(PT)and fibrinogen.Results:The experimental results were as follows:1.Ultrasonography of vena cava filterUltrasonography showed that the transverse section of jugular vein in goats was circular and well-defined hypoechoic image with an average diameter of 10.15±1.08 mm.Ultrasound guided implantation of vena cava filter showed artifacts at the tip of the catheter sheath was high echo The vena cava filter showed reticular medium echo image.The implanted vena cava filter was well developed.The foot of the filter did not cause deformation and damage to the vascular wall.The size of the filter was measured at 14.5×31.7 mm.2.X-ray imagingX-ray imaging showed that the implanted filter presented a conical high density image.One filter was released outside the blood vessel,it was not fully deployed.3.Thrombus capturingThe thrombus could be captured by the filter after thrombus injection.The average weight of the autologous thrombus which was injected into to the jugular vein was 3.14±0.29 g,the thrombus was captured by the filter weighed 3.06±0.56 g after autopsy,which showed that the implanted filter had good ability to capture thrombus.4.Changes of leukocyte parametersThe WBC count at the 1st day and the 2nd day after operation were 14.37±1.78×10~9/L,13.95±0.95×10~9/L,which was significantly higher than baseline value,it returned to baseline value at the 4th day after operation.The WBC count of the control group were13.87±0.74×10~9/L and 13.17±0.75×10~9/L at the 1st and the 2nd days after operation,respectively,which were significantly higher than baseline value,and returned to normal level on the 3rd day after operation.5.Changes of four parameters of hemagglutinationThe values of APTT,PT and TT in the control group were significantly shorter than those at the 1st day after operation,and recovered to the baseline values at the 5th day after operation.The values of APTT,PT and TT in the experimental group were significantly shorter than those in the 1st day after operation,and recovered to the baseline values at the 5th to 7th day after operation.The FIB content in the control group increased extremely significantly at the 1st day after operation;in the experimental group it increased extremely significantly at the 1st day after operation,at the 2nd day after operation it was significantly higher than that at the 1st day before operation,the FIB content in two groups were recovered to the baseline values at the 3rd to 4th day after operation.6.Anatomical observationThe filter implanted into the blood vessel was fully deployed,the filter did not tilt,there were clots attached to the filter mesh.Visible intimal damage at the site of filter attachment were not observed at the site of filter implantation.One filter was implanted into muscle,it was wrapped and ill-expanded.The appearance of the lungs and heart was normal,their texture was uniform without embolism.7.Changes of vascular intima at vena cava filter implantation siteTissue section showed that the vein tissue structure of the control group was normal,and inflammatory cell infiltration was not observed in the intima,media and adventitia of the blood vessel.Intimal hyperplasia was not found in the filter implantation site of the experimental group,and inflammatory cell infiltration was not found in all layers of the blood vessel wall.Conclusions:The vena cava filter could be successfully implanted into the jugular vein of goats by the guidance of B-ultrasound.It could effectively catch thrombus,and without pulmonary embolism occurred in experimental animals.The inflammatory reaction of the body was mild and there was a little affection on coagulation function.