不同数量血栓栓塞对肺血栓栓塞症犬血流动力学的影响

目的比较不同数量血栓柱栓塞对犬肺血栓栓塞症(PTE)模型血气、血流动力学的影响。方法将长塑胶导管置于左下肺动脉,经塑胶导管注入3段(PTE 1组)或5段(PTE 2组)血栓柱,分别监测栓塞前、栓塞1h及1周后生命体征、血流动力学参数;术后全程肌内注射氨甲环酸。结果PTE 1组栓塞1h后呼吸频率、心率较栓塞前明显加快(P<0.05);PTE 2组PaO_2/FiO_2明显降低、平均肺动脉压(MPAP)及肺血管阻力(PVR)明显升高(P<0.05),但1周后恢复至栓塞前水平。结论用血栓柱栓塞犬肺叶动脉,并用氨甲环酸抑制纤溶,可建立时间较长的PTE模型。在栓塞急性期较多血栓引起生命体征、血气及血流动力学较明显的变化,但1周后这种变化逐渐恢复。

Effects of different quantities of thrombus on blood gases and hemodynamic parameters in canine pulmonary thromboembolism model with selective pulmonary artery embolization

Objective To establish an animal model with pulmonary thromboembolism and to inves- tigate the effects of different quantifies of thrombus on vital signs,blood gases and hemodynamic parameters in the model.Methods 15 canines were embolized with the thrombus cylinders into left lower pulmonary arter- y.The canines were divided into three groups:sham group(n=5),PTE group 1(n=5):embolized with less embolus composed of three thrombus cylinders,PTE group 2 (n=5):embolized with more embolus composed of 5 thrembus cylinders.Swan-Ganz float catheter was used to guide a plastic duct with bore of 5.5 mm se- lectively into the left lower pulmonary artery by X-ray fluoroscopy.Respiratory rate(RR),heart rate(HR), blood pressure(BP) and blood gases were measured at the time before embolization,1 hour and 1 week after embolization.Hemodynamic parameters were recorded.Results RR and HR increased significantly after 1 hour of embolization in the 2 PTE groups(P<0.05);PaO_2/FiO_2,mean pulmonary arterial pressure(MPAP) and pulmonary vascular resistance (PVR) altered significantly than baseline values after one hour of emboli- zation in PTE group 2,with MPAP,PVR increasing and PaO_2/FiO_2 decreasing(P<0.05),and these param- eters returned to baseline values one week later.Conclusion A canine model with pulmonary thromboembo- lism can be established by the guidance of Swan-Ganz float catheter.The gas exchange and hemodynamic parameters are changed with the quantities of thrombus at acute embolic stage.