East Carolina Unveristy, Greenville, NC, USA.
J Clin Monit Comput. 2009 Dec;23(6):347-53. doi: 10.1007/s10877-009-9202-z. Epub 2009 Sep 13.
The project aimed to design an instrument that can provide visual, quantitative feedback to medical students and help them develop intuitive, tactile-based injection skills.
The instrument uses force and displacement sensors to find flow impedance, the ratio of the pressure applied to fluid in the syringe to the fluid flow rate, of different tissues. A software program utilizes these flow impedances to identify needle tip location-either joint or tendon. Injection experiments with pork feet were completed to collect flow impedance data when the needle tip was located in joint or tendon. Injections used deionized water and aqueous pullulan solutions to study the instrument's effectiveness when medical therapies of different viscosities are injected. For each solution, at least 13 injections were conducted. The mean and standard deviation of the flow impedances from injections with each solution were obtained.
In all experimental cases, the flow impedance demonstrated by the tendon is a number of times higher than that of the joint cavity: the impedance ratios (tendon to joint cavity) for water, 3 w/w% pullulan, and 15 w/w% pullulan are 74, 62, and 6, respectively.
The results confirmed the concept of using flow impedance to index the needle tip location-whether the tip is positioned in joint or tendon. This instrument's user interface can serve as a training aid for medical students and infrequent operators.
本项目旨在设计一种仪器，为医学生提供直观、定量的反馈，帮助他们发展基于直觉和触觉的注射技能。
该仪器使用力和位移传感器来测量不同组织的流动阻抗，即注射器中施加的压力与流体流速之比。一个软件程序利用这些流动阻抗来识别针尖的位置——关节或肌腱。使用猪脚进行注射实验，以收集针尖位于关节或肌腱时的流动阻抗数据。使用去离子水和水合普鲁兰溶液进行注射实验，以研究当注入不同粘度的医学治疗药物时仪器的效果。对于每种溶液，至少进行了 13 次注射。获得了每种溶液注射的流动阻抗的平均值和标准偏差。
在所有实验情况下，肌腱的流动阻抗都比关节腔高几个数量级：水、3 w/w%普鲁兰和 15 w/w%普鲁兰的阻抗比（肌腱与关节腔）分别为 74、62 和 6。
结果证实了使用流动阻抗来指示针尖位置的概念——针尖是否位于关节或肌腱中。该仪器的用户界面可以作为医学生和不常操作的人员的培训辅助工具。
