Objective:TEstablishing the model of the Chinese miniature pigs during cardiopulmonary bypass(CPB),and to observe the effects of cardiopulmonary bypass on porcine mesenteric microcirculation.Methods:A total of 18 healthy Chinese miniature pigs were separated into A,B two groups randomly,9 pigs were served as trials and another 9 pigs were served as controls.The two groups were both injected 5％azo-blue 0.lml/kg into jugular veins after the intravenous anesthesia.All pigs were operated by mid-sternal thoracotomy,and establish the model of cardiopulmonary bypass by ascending aorta and right atrium intubations.The A,B two groups were both operated by cardiac intubations after the intravenous anesthesia.A group was connected with the CPB machine and circulated two hours.The diameters and velocities of the mesenteric arterioles of the two groups were calculated and recorded by BI-2000 at the point of CPB 30min,CPB 60min and CPB 120min.The blood visible components(WBC,RBC and PLTs)of the two groups were recorded before CPB and at the point of CPB 120min.The pathological changes of the partial mesentery tissues were also observed under the light microscope.Results:The diameters of the arterioles in the experimental group were(267.1±10.1),(225.0±5.1),(183.5±5.9)/(×10-5/m),(151.7±5.1)/(× 10-5/m)at the point of before CPB,CPB 30min,CPB 60min and CPB 120min.With the prolongation of CPB,the diameters of the arterioles gradually decreased,and the difference was statistically significant(P＜0.05),and except for before CPB,the diameters of the arterioles at all other time points in the experimental group were significantly smaller than that of the control group(P＜0.05).The blood flow velocities of the arterioles in the experimental group were(20.8±0.6),(18.7±0.4),(15.6±0.5)/(×10-4 m/s),(13.7±0.4)/(×10-4 m/s),at the point of before CPB,CPB 30min,CPB 60min and CPB 120min.With the prolongation of CPB,the blood flow velocities of the arterioles gradually decreased,and the difference was statistically significant(P＜0.05),and except for before CPB,the blood flow velocities of the arterioles at all other time points in the experimental group were significantly smaller than that of the control group(P＜0.05).The OD value of the experimental group was(4.4±0.7)×10-3,while the OD value of the control group was(2.3±0.6)×10-3.The capillary permeability of the experimental group was significantly higher than that of the control group(P＜0.05).The red blood cells,white blood cells,and platelets in the experimental group were(30.8±0.9),(154.9±10.5),(2 062.7±150.4)/(×108/L),respectively at the point of CPB 120min.The number of red blood cells and platelets was significantly lower than that of the control group,while the number of white blood cells was higher than that of the control group(P＜0.05).The mesenteric tissues of the experimental group showed significant pathological changes under the light microscopy compared to the control group,characterized by blood cell aggregation and wall adhesion.Conclusions:CPB can cause significant damage to the mesenteric microcirculation in Chinese miniature pigs.
维普
万方数据