The Animal Experimental Studies On Organic Protection Undergoing Video-Assisted Thoracoscopic Cardiac Surgery

【Purpose】1,To compare the perfusion pressure between cardiopulmonary bypass through improved intubations of femoral artery-femoral vein and routine in identical flow on organic perfusion such as brain,lung,liver,kidney,intestines,etc.2,To observe the extent of lung tissue damage after undergoing extracorporeal circulation for video-assistant thorascopic operation in dogs.3,To observe the state of myocardial damage and study the myocardial protective effect of aprotinin after extracorporeal circulation of video-assisted thorascopic operation in dogs.【Methods and Result】Three sections were included in our study.PartⅠ:The observation of effect on organic perfusion undergoing Video-Assisted Thoracoscopic cardiac Surgery.Methods :Twenty dogs with body weight from 10-15kg were randomly divided into two groups: thoracoscope group (group A .n=10), routine group (group B .n=10). Group A's CPB was set up by the right femoral artery -femoral venous for completely video assisted cardiac operations, while group B's CPB was set up by the aorta - caval vein.The perfusion pressure of innominate artery and left common artery,superior mesenteric artery,renal artery,homonymy and opposite side popliteal artery and the pressure of concomitant vein were measured at the following time points:instantly after induction of anesthesia(T1),before aortic clamping(T2),fifteen minutes after aortic clamping(T3),fifteen minutes after aortic opening(T4),twenty minutes after stop(T5).The venous blood samples were collected at the previously mentioned time points and venous oxygen saturation were measured. Results: There were no significant differences between the two groups in the arterial perfusion pressure ,besides thoracoscope group have higher perfusion pressure than routine group at homonymy popliteal artery(P<0.01). Thoracoscope group's venous pressure in superior mesenteric vein,renal vein,homonymy and opposite side popliteal vein were higher than routine group's at the following time points :before aortic clamping,fifteen minutes after aortic clamping and fifteen minutes after aortic opening(P<0.05). Thoracoscope group's venous oxygen saturation in superior mesenteric vein,renal vein,homonymy and opposite side popliteal vein were higher than routine group's at the following time points :before aortic clamping,fifteen minutes after aortic clamping and fifteen minutes after aortic opening(P<0.05).PartⅡ:The observation of lung tissue damage undergoing Video-Assisted Thoracoscopic cardiac Surgery.Methods :Thirty immature dogs with a body weight of 10-15kg were randomly divided into three group s, 10 dogs each group,the route group (A group) , the thorascope group(B group) and the control group (A group). The route l group's ECC was established as route and the thorascope group's was set up by the right femoral artery,femoral venous. The control group only takes the breathing machine without operation. Hemodynamics, lung compliance,airway resistance,and arterial blood gas were assessed at the following time points:after induction of anesthesia(T1),half an hour after aortic opening(T2),one hour after aortic opening(T3)one half an hour after aortic opening(T4). Then artery-alveolar O2 pressure ratio(PaO2/PAO2),pulmonary vascular resistance index(PVRI),oxygenation index(OI) were calculated. Lung water and malondialdehyde content were assessed.Histological evaluation was also made. Results: PartⅡ: There were no significant differences on pulmonary function parameters between A and B groups after operation, though contrast with A group, In the B group, airway resistance and pulmonary vascular resistance index were higher , lung compliance ,artery-alveolar O2 pressure ratio and oxygenation index(OI)were lower, less lung water was observed and the malondialdehyde content in the pulmonary tissue was lower. There were no significant differences on pulmonary function parameters in C group. But with contrast A and B,airway resistance , pulmonary vascular resistance index , lung water and malondialdehyde were lower , lung compliance ,artery-alveolar O2 pressure ratio and oxygenation index(OI) were higher in C group. Under the optical microscope, pulmonary architecture was destroyed, abundant intraalveolar neutrophils,interstitial edema were seen in two group, but all of histological change in B group is more serious than A group. The pulmonary architecture was normal in C group.PartⅢ: The observation of Myocardial protection on aprotinin undergoing Video-Assisted Thoracoscopic cardiac Surgery.Methods :Twenty puppies with weight 10-15kg were randomly divided into 2 groups. CPB was set up by the right femoral artery,femoral venous. The control group(Group A) don't use any drug . aprotinin was administered to the experimental group(Group B) in CPB.The radial arterial blood samples were collected at the following time points:after induction of anesthesia(T1), ten minutes after aortic clamping(T2),half an hour after aortic clamping(T3), half an hour after aortic opening(T4), two hours after CPB(T5), twelve hours after CPB ( T6 ). The cardiac troponin I(cTnI) , MB isoenzyme of creatine kinase(CKMB) ,,interleukin-8(IL-8) , tumor necrosis factor-α(TNF-α) and interleukin-10(IL-10) were measured . Results:There were no significant differences between two groups on the levels of CKMB, cTnI, TNF-α, IL-8 and IL-10 before aortic clamping(P>0.05). The concentration of CKMB,cTnI,TNF-α,IL-8 gradually raised(P<0.05) and arrived to the highest two hour after CPB in group A and then fell.While the persistence of cTnI behaved otherwise, maintaining a high level.But All above mentioned after aortic clamping were higher significantly than T1 .The level of CKMB, cTnI, TNF-αand IL-8 in group B were lower than that of group A after aortic clamping(P<0.05),but IL-10 in group B was remarkably higher(P<0.05). The level of cTnI declined at T5 in group B(P<0.05).【Conclusions】It demonstrated the improved femoral CPB has a similar perfusion pressure with routine CPB and a higher vein pressure than routine CPB below inferior vena cava after aortic intubations.So this experiment provided theoretical evidence for the organic protection of infants'thorascopic extracorporeal circulation.. lung injury caused by extracorporeal circulation for video-assistant thorascopic and route extracorporeal circulation in dogs showed similar effct. Degree of myocardial damage of the children undergoing extracorporeal circulation of video-assisted thorascopic operation was conspicuous about two hour after stop, but did not deteriorate.Aprotinin has satisfactory effect of myocardial protection from the postoperative inflammatory reaction caused by extracorporeal circulation of thorascopy.