| Objective:To aid in the development of minimally-invasive surgical hemostatic clips and how to use vascular clips correctly,we determined the accuracy of an improved formula for determining the minimum occlusive force(MOF)of a vascular clamp on rats’ abdominal aortas,to compare our findings with the calculated theoretical MOF.And examined the injury and recovery of the rat abdominal aorta using two kinds of arterial hemostatic clips.Methods:This experiment is divided into two parts:1、We created a vessel closure model and developed a formula for calculating the theoretical MOF of arterial vessels when they are occluded,the formula utilising the blood pressure in the blood vessel,its diameter,and the width of the vascular clamp.We then measured the actual MOF in 24 rat abdominal aortic segments with different diameters and different blood pressures,and compared the theoretical and actual MOF.2、Sprague–Dawley rats(n=108)were divided into a metal microscopic hemostatic clip group or a new disposable minimally-invasive hemostatic clip group.Each group included four subgroups,with clamping force of 30 g,60 g,90 g,or 120 g.Intimal injury of blood vessels was examined by scanning electron microscopy,histomorphology,and immunohistochemistry.Results:The first part of the experiment:Statistical analysis of the experimental data showed a probability of 0.315,which means that,under the condition of normal distribution,the difference between theoretical(MOF=2×(1/2×π×D×W×BP))and actual MOF is not significant at the α=0.05 level.The second part of the experiment:The metal hemostatic clip at 60 g had a vascular injury grade of 3,with an average immunohistochemical score of 5.87±1.17,and positive P-selectin expression.Both hemostatic clips at 90 g had vascular injury grades of 3,with averaged immunohistochemical scores of 7.03±1.47(disposable hemostatic clip)and 7.93±2.97(metal hemostatic clip),and positive P-selectin expression.The disposable hemostatic clip and metal hemostatic clip injury at120 g had vascular injury grades of 3 and 4,respectively,with averaged immunohistochemical scores of 9.8±1.75 and 10.06±1.87,respectively,and strong P-selectin expression.In healing experiments,the injury was grade 1 with intimal cell proliferation,the surface of vascular intima was colorless with positive cells accounting for ≤10%,and there was negative P-selectin expression on the intima surface.Conclusion:The actual measured MOF tended to be consistent with the theoretical MOF calculated by the formula we developed.According to the theoretical formula of the minimum clamping force,a safe and appropriate vascular clamp can be selected,and the safe range of the actual minimum clamping force can be predicted for clinical reference.And the disposable hemostatic clip causes less injury to the arterial wall during clamping than the metal hemostatic clip,which is advantageous for clinical application.Further,blood vessel can repair hemostatic clips injury. |
