公开(公告)号：US5394732A

公开(公告)日：1995-03-07

申请号：US119790

申请日：1993-09-10

申请人： David A. Johnson ,  Douglas P. Miller ,  Keith J. Manica ,  William M. Dormont ,  Christopher J. Welsh ,  William R. Mandel

发明人： David A. Johnson ,  Douglas P. Miller ,  Keith J. Manica ,  William M. Dormont ,  Christopher J. Welsh ,  William R. Mandel

IPC分类号： A61M1/36 ,  G01N29/02 ,  G01N29/032 ,  G01N29/22 ,  G01N29/32 ,  G01N29/34 ,  G01N29/36 ,  G01N29/38 ,  G01N29/44

CPC分类号： G01N29/4427 ,  A61M1/3626 ,  G01N29/032 ,  G01N29/223 ,  G01N29/32 ,  G01N29/34 ,  G01N29/36 ,  G01N29/38 ,  G01N2291/015 ,  G01N2291/02433 ,  G01N2291/02466 ,  G01N2291/102

摘要： Inclusions in a liquid flow, such as air bubbles in a blood flow, are detected by transmitting a signal through the fluid and receiving and interpreting the received signal based on the expected degree of attenuation for the liquid and the inclusions. The amplitude of the transmitted signal is automatically adjusted to maintain a constant average amplitude of the detected signal, thus compensating for changes in the detection environment. The average amplitude of the transmitted signal is controlled by integrating the received signal using an integrator with a time constant longer than the time constant of the expected inclusion signals, and comparing the integrated signal to a constant reference level.The presence of microbubbles is detected and a signal comprising a string of high frequency pulses is generated while the microbubbles are present. By counting the pulses, in conjunction with knowledge about the flow of liquid and the anticipated size of the microbubbles, an estimate of the total amount of air infused into the patient within a given time period is calculated.A tubing holder for retaining a flexible tube in an inclusion detector has tubing retention grooves formed into tubing engagement faces, the tubing engagement faces being spaced closer together than the tube diameter. The tube is inserted into the tubing holder by compressing and deforming it against the tubing engagement faces, until it reaches the tubing retaining grooves.

摘要翻译： 通过传输信号通过流体并基于液体和夹杂物的预期衰减程度来接收和解释接收到的信号来检测液体流中诸如气流中的气泡的夹杂物。 自动调整发送信号的振幅，以保持检测信号的平均幅度恒定，从而补偿检测环境的变化。 通过使用积分器对接收到的信号进行积分来控制发送信号的平均幅度，时间常数大于预期包含信号的时间常数，并将积分信号与恒定参考电平进行比较。 检测到微气泡的存在，并且在存在微泡的同时产生包括一串高频脉冲的信号。 通过计算脉冲，结合关于液体流动和微泡预期尺寸的知识，计算在给定时间段内输入患者的总空气量的估计。 用于将柔性管保持在夹杂物检测器中的管保持器具有形成为管接合面的管保持槽，管接合面与管直径相距更靠近在一起。 管通过压缩并使其变形到管接合面而插入管夹中，直到其到达管保持槽。