The Effect On Arterial Pressure Of Internal Iliac Artery Net After Internal Iliac Artery Or Abdominal Aorta Blockade:An Experiment Study

Objective: With the development of society, the incidence of pelvic fractures for high-energy injury increase dramatically.The patients presenting with significant hemodynamically unstable pelvic fractures have serious life menace and high mortality.Arterial bleeding is an important reason of hemodynamically unstable pelvic fractures. Pelvic fractures secondary to arterial bleeding are present in only about 5% to 10% of the cases,however, pelvic arterial bleeding is brisk and difficult to control. Controlling pelvic arterial hemorrhage can be a challenging problem to orthopedic surgeons.At first ligation of internal iliac artery could be lifesaving. Margolies et al. firstly reported using angiography to diagnose and treat pelvic arterial hemorrhage. Angiographic embolisation can be considered as a most effective approach to the pelvic fractures treatment for arterial bleeding and is widely used at home and abroad after doctors'exploration and practice now.Recently the scholars of our country treat massive bleeding of pelvic fractures with temporary occlusion of abdominal aorta successfully. Internal iliac artery blockade includes the ligation of internal iliac artery and the angiographic embolization.The purpose of this experiment is to have a depth and intuitionistic understanding of pressure changes after the artery blockade and to solide theoretical basis and provide reference for further clinical application.Methods: Five healthy goats were selected,including two male goats and three female goats.They were the goats aged 9-15months with a mean(12.53±2.24 )months and the weight of 25-30kg with a mean (28.17±1.86) kg.All goats were provided by the department of animal laboratory,the third hospital of Hebei medical university.All goats should be applied to abrosia before operation.The goats were anesthetized by intramuscular injection of ketamine ,diazepam and 3% pentobarbital sodium.They were fastened to the operation table by the ropes,which lay on their back. We established a venous access on the hind leg.After opening the circuit, lactated Ringer solutions should be infused to maintain blood volume.Abdomen was open through a midline incision.Abdominal aorta could be visible after incision skin,subcutaneous tissue, abdominal muscle,peritoneum.Then the common iliac artery, bilateral external iliac arteries and internal iliac arteries could be found. Abdominal aorta and internal iliac arteries should be separated by blunt dissection carefully. A indwelling needle was inserted into internal iliac artery toward heart at 2.5cm distance from the initial site of internal iliac artery and connected to a invasive arterial pressure instrument of Philips.Then we could measure normal internal iliac artery pressure.Firstly we measured the pressure of unilateral internal iliac artery blockade and the pressure of bilateral internal iliac artery blockade after contralateral internal iliac artery blockade with bulldog clamp blocking. Then we measured the pressure after abdominal aorta and bilateral internal iliac artery blockade with bulldog clamp blocking abdominal aorta again.At last we could measure the pressure of abdominal aorta blockade after loosing bulldog clamp. The experimental methods of five goats was the same with recording the mean value of all pressures. During the operation,the solutions volume should be adjusted with the amount of bleeding.The narcotic should be added base on goats'reaction to keep the goats silence,which could make the measure more accurate.Finally the data was organized. All statistical analysis were performed using SPSS for Windows,version 13.0.Randomized block design was used and P value was set at 0.05 for the statistical significance.Result: Normal internal iliac artery pressure was(57.84±13.46)mmHg and the pressure of unilateral internal iliac artery blockade was(38.40±17.39)mmHg. The drop in mean pressure with unilateral internal iliac artery blockade was 33.61% compared with normal internal iliac artery pressure. The pressure of bilateral internal iliac artety blockade was(29.70± 12.16)mmHg. The drop in mean pressure with bilateral internal iliac artery blockade was 48.65 % compared with normal internal iliac artery pressure.The pressure of abdominal aorta and bilateral internal iliac artery blockade(32.80±17.02)mmHg. The drop in mean pressure with abdominal aorta and bilateral internal iliac artery blockade was 43.29%compared with normal internal iliac artery pressure.The pressure of abdominal aorta blockade was (29.20±18.52)mmHg. The drop in mean pressure with abdominal aorta blockade was 49.51% compared with normal internal iliac artery pressure. The study showed the pressures of internal iliac artery dropped with different meathods significantly after randomized block design and there was significant difference statistically(P<0.05).But there was no significant difference among different meathods(P>0.05).Conclusion: Our experimental results show the pressure of internal iliac artery drops significantly after abdominal aorta or internal iliac artery blockade,while there was no significant different among different meathods. The pressure values of internal iliac artery do not drop to 0mmHg with any meathods of abdominal aorta or internal iliac artery blockade and a little of blood can continue to flow.According to actual situation clinically, we can choice appropriate method aimed at controlling arterial hemorrhage.