Development of a thermodynamic control system for the Fontan circulation pulsation device using shape memory alloy fibers
Development of a thermodynamic control system for the Fontan circulation pulsation device using shape memory alloy fibers
复制标题
利用形状记忆合金纤维开发Fontan循环脉动装置热力控制系统
DOI：
10.1007/s10047-015-0827-z
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发表时间：
2015
期刊：
影响因子：
1.3
通讯作者：
Yambe T
中科院分区：
文献类型：
--
作者：
Yamada A;Shiraishi Y;Miura H;Yamagishi M;Yambe T
Fontan手术是儿科先天性心脏病患者循环重建的常见手术治疗方法之一。在方丹循环中，低搏动可能诱发局部肺缺血，并可能损害肺外周内皮细胞的发育。为了促进方潭循环的肺循环，我们开发了一种使用形状记忆合金纤维从全腔肺连接外部附着的儿科肺循环搏动装置。在本研究中，我们为该装置开发了一种新的热控制系统并对其功能进行了测试。我们在该装置上安装了16根纤维，沿周向平行连接ePTFE移植物。为了提供最佳的收缩，我们设计了新的热控制系统。该系统由一个热敏电阻、一个压力传感器和一个由自适应热力学传递函数控制的调节器组成。对参数进行了监测，计算了接枝表面的传热函数和压力分布。然后，我们检测并比较了动态收缩压力和表面温度的变化。结果表明，通过应用基于新反馈系统分析的控制，周向收缩压力提高了35%。自适应热力学调节有助于选择接枝表面温度的备选阈值。该系统能够对装置产生的脉动流进行有效的收缩。
The Fontan procedure is one of the common surgical treatments for circulatory reconstruction in pediatric patients with congenital heart disease. In Fontan circulation, low pulsatility may induce localized lung ischemia and may impair the development of pulmonary peripheral endothelial cells. To promote pulmonary circulation in Fontan circulation, we have been developing a pediatric pulmonary circulatory pulsation device using shape memory alloy fibers attached from the outside of total cavopulmonary connection. In this study, we developed a new thermal control system for the device and examined its functions. We mounted on the device 16 fibers connected in parallel around an ePTFE graft circumferentially. To provide optimized contraction, we designed the new thermal control system. The system consisted of a thermistor, a pressure sensor, and a regulator that was controlled by the adaptive thermodynamic transfer functions. We monitored the parameters and calculated heat transfer function as well as pressure distribution on the graft surface. Then we examined and compared the dynamic contractile pressure and changes in surface temperature. As a result, by the application of the control based on the new feedback system analysis, the circumferential contractile pressure increased by 35 %. The adaptive thermodynamic regulation was useful for the selection of alternative thresholds of the surface temperature of the graft. The system could achieve effective contraction for the pulsatile flow generation by the device.