瓣膜置换术——围体外循环心脏直视手术血液流变特性的变化

Valvular Replacement——Changes of Blood Rheological Properties by Open Heart Surgery with Extracorporal Circulation

瓣膜置换病例[31例]在围手术期的血液流变特性变化规律与ASD、VSD病例不同之处甚多,即这类患者血液流变特性的改变除与体外循环心脏直视手术本身有关外,还与疾患种类、手术方式等因素有关。其主要特征为: 1.该类病例术前的血液粘、弹指标和RBC聚集指标多已高于正常水平,说明瓣膜疾患对患者血液流变特性有重大影响; 2.术前,患者的血小板计数及粘附率均略低于ASD、VSD病例,但仍在正常范围;体外凝血实验亦正常; 3.术中,各血液流变参数的变化大体上与ASD、VSD病例一致,表示血液稀释和人工心肺机的影响仍是患者血液流变特性发生变化的主因; 4.术后,患者血液流变特性变化的一个最显著的特点是,粘、弹指标回升幅度小,且反复波动,缓慢上升趋势可持续10天以上; 5.血小板计数指标在术后72小时内明显低于ASD、VSD病例,且术后5天以上方能与术前水平相当,但其在整个围手术期的变化规律则与ASD、VSD病例相似; 6.血小板粘附功能明显受到抑制,表现在其达到术前水平的时间及其高峰日多被推迟。 与前文中ASD、VSD病例相较,可发现瓣膜置换病例有许多特殊的病理生理过程影响着围手术期的患者血液流变特性。深入研究患者血液流变特性的变化及其原因,必将有助于加深对该疾患的认识,并为临床诊、疗、监护提供参考。

The rules of hemorheology property changes in valvular replacement cases are quite different from those of ASD & VSD repair ones, during perioperative period. That means the variations of patients' hemorheological properties closely related not only to open heart surgery itself, but also to other factors.In 31 cases of valvular replacement, the main characteristics of patients' hemorheological properties were as follows:A. before operation, many parameters, such as blood viscosity, viscoelasticity and index of RBC aggregation were deviated from normal range; these phenomena imply that valvular disease could affect patients' hemorheological properties significantly;B. platelets count and adhesive rate of platelets were a little bit lower than those cases with ASD & VSD, but still within normal ranges, The test of coagulation in vitro was also normal, in perioperative period;C. during operation, the phenomena that almost all changes of the patients'. hemorheological parameters were similar to those With ASD & VSD meant that the effects of hemedilution and artificial heart-lung machine had still been the most-important factors;D. after operation, the most significant characteristics of patient's hemorheological properties were the blood viscoelasticity and viscocity returned slowly and wavedly;E. the platelet count was lower than that in cases with ASD & VSD during the first 72 hours postoperatively, but the changing rule of similar to that in cases of ASD & VSD in perioperative period;F. platelet adhesive function was markedely inhibited for a long period of time postoperatively either its peak time or the time when it returned to perioperative level was postponed.Comparing these cases with ASD & VSD ones reported earlier, we found that there were many special pathological courses which would affect hemorheological properties in valvular replacement cases, during perioperation. Studying of these changes and their causes with hemerheological methods, might be able to have a deeper understanding on the very disease and improve the diagnosis and treatment of the disease.