轴流泵式全人工心脏的体外测试及对负荷反应特性  

In vitro evaluation of the load response characteristics of the total artificial heart with axial flow pumps

作　　者：李国荣[1] 朱晓东[1] 田步升[2] 陈海丰 

机构地区：[1]中国医学科学院阜外心血管病医院外科,北京100037 [2]长治医学院附属和平医院,山西长治046002 [3]长治商业医院,山西长治046000

出　　处：《生物医学工程与临床》2011年第3期214-217,共4页Biomedical Engineering and Clinical Medicine

摘　　要：目的 在体外模拟循环台测试轴流泵式全人工心脏的基本负荷反应特性,为探索生理性控制方案提供基础.方法 轴流泵式全人工心脏样机采用2个轴流泵共同设置在刚性外壳中,直径65mm,长度70mm.于模拟循环台上串联组成全人工心脏的2个轴流泵,在外周动脉和肺动脉阻力不变的条件下观测前、后负荷变化对心输出量的影响.结果 在前负荷固定不变的条件下,增加后负荷时心输出量逐步下降,增大泵转速可对抗后负荷对输出量的抑制,泵转速设定为右心泵8500r/min、左心泵11 000r/min时,心输出压为13.30kPa（100mmHg）和输出量6L/min.当后负荷增人到26.70kPa（200mmHg）时心输出量下降为0L/min.在后负荷固定不变的条件下,前负荷的增加不导致心输出量明显改变.设定左心泵转速为11000dmin、右心泵转速8500 r/min时前负荷由0.27 kPa（2 mmHg）增加到1.87 kPa（14 mmHg）,流量基本维持在7 L/min.结论 轴流泵式全人工心脏对后负倚增加表现出明屁的流量抑制趋势,此趋势可通过调节泵转速改善.轴流泵式全人工心脏对前负荷反应不明显,有别于自然心脏,其机制及调节意义尚待进一步研究.Objective To test the total artificial heart with axial flow pumps in a mock circuit, and explore the physiological basis of the control program. Methods The prototype of the total artificial heart was constructed by 2 axial flow pumps as substitute for the left and right heart pump respectively. The two blood pumps were housed in a rigid shell, with diameter of 65 mm and length of 70 mm. The performance of the total artificial heart was tested by concatenating the 2 axial flow pumps in a mock circuit. Results When the preload was fixed, the cardiac output was gradually decreased with the increase in afterload. The inhibitory effect of the afterload on cardiac output was attenuated by increasing the pump flow rate. In the current study, the speed of the left and right pumps were set at 11 000 r/min and 8 500 r/min respectively, which led to a flow rate of 5 L/min against 13.3 kPa（100 mmHg） after load. However, when the afterload increased to 26.7 kPa（200 mmHg）, the flow rate dropped to 0. Improved pump speed could effectively compensate this trend and the increase in preload did not obviously affect the output of artificial heart when the afterload was fixed. It was observed that when the preload was changed from 0.27 kPa（2 mmHg） to 1.87 kPa（14 mmHg）, the output of the total artificial heart maintained at 7 L/min. Conclusion It is demonstrated that the cardiac output of the artificial heart is significantly restrained by the afterload while the preload exhibited little influence on it. Further investigation is needed to explore the significance of the difference in the load response characteristic between the artificial heart employed in the current study and the natural heart.

关 键 词：全人工心脏 轴流泵 心功能衰竭 人工器官 

分 类 号：R318[医药卫生—生物医学工程]