【摘要】 目的:心脏转流辅助时为克服引流管道的阻力常需在血泵入口端引入负压区,但目前尚不了解负压对血细胞机械损伤过程的影响。本文观察了负压对机械转流管道中血流溶血过程的影响。方法:应用离心式血泵建立体外模拟的循环路线,循环液体为新鲜猪血液2L,血球压积30％,循环速度0.7L/min。调节流入管道液柱高度以引入不同程度的负压区,其中A组:-5mmHg,B组:-45mmHg,C组:-90mmHg,循环时间30分钟。分阶段测定血浆游离血红蛋白浓度,计算和比较转流后溶血指数(HI)。结果:转流过程中游离血红蛋白浓度逐步升高,各组变化趋势一致,组间无显著差异。转流后HI分别为A:23.76±0.1mg/L、B:23.75±0.09mg/L、C:22.76±0.07mg/L,各组间无显著差异。结论:短期转流时负压区的存在不会对红细胞机械损伤过程产生可察觉的影响。临床中应用机械性辅助装置时可通过增加负压值安全地增加引流量。更多还原

【Abstract】 Aim: To evaluate the effects of negative pressure on Haemolysis within bypass pipe under CPB. Clinical material and method; Copied CPB was supported by a centrifugal assist pump in which fresh procine blood was used with volume of 2L, Hct of 30% and circulating speed of 0. 7L/min. Adjust the liquid-column height of afferent pipe to produce three groups of different negative pressures; Group A - 5mmHg, Group B - 45mmHg, Group C - 90mmHg. The circuiting time was 30 min. Haemolytic Index (HI) was calculated and compared after circulation according to the values of free haemoglobin concentrations measured periodically. Results; The concentrations of free haemoglobin increased gadually druing CPB and the changing tendency of each group was consistent without clinical significance. HI of each group were, A 23. 76±0.1mg/L,B 23. 75 ± 0. 09mg/L,22. 76±0. 07mg/ L, having no significant different. Conclusion; The existence of negative pressure has no perceivable effects on the mechanical injury of red blood cells (erythrocytes) in short-period bypass. Volume of CPB can be increased safely by increasing the negative pressure in clinical application of mechanical assist.更多还原