Department of Precise Medical Device, Shanghai Medical Instrumentation College, Shanghai, China.
Biomed Eng Online. 2012 Feb 1;11:5. doi: 10.1186/1475-925X-11-5.
Continuous Positive Airway Pressure (CPAP) ventilation remains a mainstay treatment for obstructive sleep apnea syndrome (OSAS). Good pressure stability and pressure reduction during exhalation are of major importance to ensure clinical efficacy and comfort of CPAP therapy. In this study an experimental CPAP ventilator was constructed using an application-specific CPAP blower/motor assembly and a microprocessor. To minimize pressure variations caused by spontaneous breathing as well as the uncomfortable feeling of exhaling against positive pressure, we developed a composite control approach including the feed forward compensator and feedback proportional-integral-derivative (PID) compensator to regulate the pressure delivered to OSAS patients. The Ziegler and Nichols method was used to tune PID controller parameters. And then we used a gas flow analyzer (VT PLUS HF) to test pressure curves, flow curves and pressure-volume loops for the proposed CPAP ventilator. The results showed that it met technical criteria for sleep apnea breathing therapy equipment. Finally, the study made a quantitative comparison of pressure stability between the experimental CPAP ventilator and commercially available CPAP devices.
持续气道正压通气（CPAP）仍然是治疗阻塞性睡眠呼吸暂停综合征（OSAS）的主要方法。良好的压力稳定性和呼气过程中的减压对于确保 CPAP 治疗的临床疗效和舒适性至关重要。在这项研究中，使用专用的 CPAP 风机/电机组件和微处理器构建了一种实验性 CPAP 通气机。为了最小化由自主呼吸引起的压力变化以及对正压呼气的不适感觉，我们开发了一种组合控制方法，包括前馈补偿器和反馈比例积分微分（PID）补偿器，以调节输送给 OSAS 患者的压力。采用 Ziegler 和 Nichols 方法来调整 PID 控制器参数。然后，我们使用气体流量分析仪（VT PLUS HF）测试了所提出的 CPAP 通气机的压力曲线、流量曲线和压力-容积环。结果表明，它符合睡眠呼吸暂停呼吸治疗设备的技术标准。最后，研究对实验性 CPAP 通气机和市售 CPAP 设备的压力稳定性进行了定量比较。
