Effects of polymyxin B-immobilized fibers in normothermic cardiopulmonary bypass.

(实验一)目的：探讨多粘菌素B固定化纤维(PMX)直接血液灌流对猪常温心脏手术的影响。方法：将10对猪随机分为两组。麻醉动物后，按常规方式建立常温体外循环。对照组动物用常温体外循环循环灌流。PMX组动物使用含有多粘菌素B-胆管纤维的内毒素清除柱进行灌流，从体外循环以80ml/min的速度进入，直到实验结束。采用间断顺行温血停搏液心脏骤停。主动脉阻断时间为34min。分别于CPB前和CPB结束后2小时测定最大心室弹性(Emax)、心输出量(CO)、左心室压(LVP)、左心室压最大上升和下降速率(LVdp/dt)和动脉血气。心功能恢复率以…百分比表示CPB前价值的年龄越大。结果：PMX组Emax、LVP、CO、-LV dp/dt、PaO2均明显优于对照组。PMX组心肌组织病理损伤轻于对照组。结论：在常温体外循环条件下，使用多粘菌素B固定的纤维直接血液灌流可以改善心肺缺血再灌注损伤。(实验2)目的：在先前的研究中，我们报道了抑制促炎症细胞因子，如肿瘤坏死因子-α和白介素1-α，改善了移植后的效果。在这项研究中，我们评估了使用我们的冠脉持续灌注器进行长期保存，结合抑制促炎细胞因子，是否改善了移植后的供心功能。方法：选用成年杂种犬。心脏骤停后用威斯康星大学(UW)溶液冲洗冠状动脉血管床。然后切除心脏，使用保存仪进行浸泡和冠脉灌流相结合的保存12h。成年杂种犬分为冠脉灌注组(CP组)和FR167653组(FR-CP组)。CP组采用4℃UW溶液浸泡和冠脉灌注。FR-CP组用4℃UW液加20 mg/L抗炎剂进行浸泡和冠脉灌注。在原位移植后2、3h，将供体动物的血流动力学参数与术前比较。比较两组冠状静脉窦血中肿瘤坏死因子-α水平及电子显微镜检查结果。结果：移植后3h，FR-CP组的心输出量(CO)、左室压(LVP)和-LVdp/dt显著高于CP组。超微结构观察显示，FR-CP组较CP组糖原保存良好。FR-CP组血清肿瘤坏死因子-α水平明显低于CP组。结论：FR-CP组移植后血流动力学明显优于CP组。使用本装置的持续预融合和浸泡联合抑制促炎细胞因子的联合保存方法改善了移植后的供心功能。较少

(Experiment 1)Purpose : The purpose of this study was to investigate the effects of direct hemoperfusion using polymyxin B-immobilized fiber (PMX) on normothermic cardiac surgery in pigs. Methods : Ten pairs of pigs were divided into two groups. After anesthesia of animals, Normothermic CPB was established in a usual fashion. Control group animals were perfused using a normothermic CPB circuit. PMX group animals were perfused using an endotoxin removal column containing polymyxin B-imrhobilized fiber, which was introduced at a flow rate of 80ml/min from CPB to the end of experiment. Cardiac arrest was obtained by intermittent antegrade warm blood cardioplegia. Aortic cross clamping time was 34 min. Maximal ventricular elastance (Emax), cardiac output(CO), left ventricular pressure(LVP), the maximum rate of increase and decrease of LVP (LV dP/dt), and arterial blood gas were measured at pre-CPB and 2hr after weaning from CPB. Cardiac functional recovery rates were expressed as a percent … More age of pre-CPB values. Results : Emax,LVP,CO,-LV dP/dt and PaO_2 were significantly better in the PMX group than in the control group. Histopathological tissue damage of the myocardium was milder in the PMX group than in the control group. Conclusion : Direct hemoperfusion using polymyxin B-immobilized fiber in the condition of normothermic CPB ameliorates ischemia-reperfusion injury of the heart and lung.(Experiment 2)Purpose : In a previous study, we reported that suppression of proinflammatory cytokines, such as tumor necrosis factor-α(TNF-α) and interleukin-1β(IL-1β), improved results after transplantation. In this study, we evaluated whether long-term preservation using our apparatus for continuous coronary perfusion, combined with suppression of proinflammatory cytokines, improves donor heart function following transplantation. Methods : Adult mongrel dogs were used. Coronary vascular beds were washed out with University of Wisconsin(UW) solution following cardiac arrest obtained. The heart was then excised and preserved for 12 h with a combination of immersion and coronary perfusion using a preservation apparatus. Adult mongrel dogs were divided into two groups : the coronary perfusion(CP) group and the FR167653 (FR-CP) group. In the CP group, a 4℃ UW solution was used for both immersion and coronary perfusion. In the FR-CP group, a 4℃ UW solution supplemented with 20 mg/L of the anti-inflammatory agent FR167653 was used for both immersion and coronary perfusion. At 2 and 3 h after orthotopic transplantation, hemodynamic parameters were compared with preoperative values of donor animals. Serum levels of TNF-αin blood from the coronary sinus and electron microscopic studies were compared between the two groups. Results : Three hours after transplantation, cardiac output(CO), left ventricular pressure(LVP) and-LV dp/dt were significantly higher in the FR-CP group than in the CP group. Electron microscopic studies showed that glycogen was well preserved in the FR-CP group as compared with the CP group. Serum levels of TNF-α were significantly reduced in the FR-CP group relative to the CP group. Conclusion : Hemodynamics following transplantation was significantly better in the FR-CP group than in the CP group. The combined preservation method of continuous per fusion and immersion using our apparatus in conjunction with suppression of proinflammatory cytokines improves donor heart function following transplantation. Less