| Objective To study the method of creating a porcine model with various degrees of intrahepatic portal vein injuries under ultrasonographic guidance. To discuss the clinical efficacy of local injection of hemostatics and radiofrequency coagulation therapy in the treatment of portal vein rupture under contrast enhanced ultrasonography (CEUS).Materials and methods①Laparotomy was performed during general anaesthesia in 16 healthy swine. After conventional ultrasound examinations on the segmental and subsegmental branches of hepatic portal vein, four lesions of portal venous injures per animal were produced under the ultrasonographic guidance with the diameter and flow rate of the portal vein measured previously.②The diameter(d) of the lesions produced in each animal ranged as followed:d<1mm, (1≤d<2)mm, (2≤d<3) mm and d>3mm, according which the lesions were assigned into group 1, group 2, group 3 and group 4.③The lesions were classified according the Liver Injury Scale of American Association for the Surgery of Trauma (AAST), with the area of ongoing hemorrhage and lesions measured under CEUS and the volume of per minute blood flow calculated by the diameter and flow rate.④The portal venous injuries in the same degree were randomized into two groups which were treated with local injection of hemostatics or radiofrequency coagulation therapy. The bleeding time, the dosage of hemostatics and the output power of radiofrequency coagulation therapy were all recorded.⑤CEUS were performed 10 minutes after treatment to validate the exist of ongoing hemorrhage and the ultrasonic data were compared to operative photographs. The gross examinations were performed 2 weeks after treatment. Results①All the 64 lesions of portal venous injuries in the 16 animals were successfully produced with ongoing hemorrhage observed. The injuries were demonstrated as the abnormal local collection and enhancement.②The average flow rate of group 1 and group 2 were significantly lower than those of group 3 and group 4, (P<0.05).③The bleed flow per minute were as followed:(3.8±0.5)ml in group 1, (12.6±3.7)ml in group 2, (46.3±12.5)ml in group 3 and (86.7±21.5)ml in group 4, increasing with the increase of the diameter of lesions.④The area of lesions under CEUS examination showed significant correlation with the classification according to the liver injury scale of AAST, (P<0.05).⑤The average dosage of a-cyanoacrylate used in group 4 was (6.6±2.4)ml, which was significantly larger than the other three groups, (P<0.05).⑥Successful rate of the active hemorrhage treated with local injection of hemostatics in four groups were 100%(8/8),100%(8/8),62.5%(5/8) and 0%(0/8) respectively, however, those treated with radiofrequency were all 100%. The efficiency of radiofrequency coagulation therapy was significantly higher than that of local injection therapy in group 4, (P<0.05).⑦The average bleeding time in lesions treated with local injection were (16.7±2.0)s in group 1, (23.0±3.7)s in group 2 and (24.0±7.2)s in group 3 which were significantly shorter than those treated with radiofrequency coagulation, (98.5±16.8)s in group 1, (110.8±24.1)s in group 2 and (137.2±31.3)s in group 3, (P<0.05).⑧Liver section showed inflammatory cells infiltrated into periportal region after local injection of hemostatics, on the other hand, preserved liver parenchyma surrounded by inflamed granulated tissue after radiofrequency coagulation therapy.Conclusions Hepatic traumatic model with portal vein injuries could be successfully created under ultrasonographic guidance. The radiofrequency coagulation therapy under ultrasonographic guidance is effective in treatment of segmental and subsegmental portal vein injuries, and the injection of hemostatics is effective in treating injuries of which the diameter is less than 3mm.
|
PDF Full Text Request