Lu Liangsong, Wang Yixuan, Shen Guolang, Du Minghua
Beihang University, Beijing, China.
Ceramic University, Jiangxi, China.
Front Bioeng Biotechnol. 2024 Oct 23;12:1477886. doi: 10.3389/fbioe.2024.1477886. eCollection 2024.
Existing Mechanical Insufflation-Exsufflation (MI-E) devices often overlook the impact of cough airflow pressure on mucus clearance, particularly lacking in control over airway pressure during the expiratory phase, which can lead to airway collapse and other types of airway damage. This study optimizes the design of cough assist system and explores the effectiveness of PID and adaptive control methods in regulating airway pressure. The adaptive control method compensates for hose pressure drop by online estimation of the ventilatory hose characteristics. It achieves precise tracking of target pressure and ensures the generation of peak flow rates effective for mucus clearance, even in the absence of known patient lung physiological states and unknown hose leakage parameters. Through a series of comparative experiments, this paper confirms the significant advantages of adaptive control in reducing oscillations and overshoot, capable of more stable and precise airway pressure adjustments. This improved control strategy not only enhances clinical safety but also significantly improves therapeutic outcomes and reduces the risk of complications. The findings indicate that the revamped cough assist system, employing an adaptive control strategy, can effectively prevent airway damage during assisted coughing, offering a safer and more effective sputum clearance solution for critically ill patients with expectoration disorders.
现有的机械吸气-呼气（MI-E）设备常常忽视咳嗽气流压力对黏液清除的影响，尤其是在呼气阶段缺乏对气道压力的控制，这可能导致气道塌陷和其他类型的气道损伤。本研究优化了咳嗽辅助系统的设计，并探索了比例-积分-微分（PID）控制和自适应控制方法在调节气道压力方面的有效性。自适应控制方法通过在线估计通气软管特性来补偿软管压力降。即使在患者肺部生理状态未知且软管泄漏参数未知的情况下，它也能实现对目标压力的精确跟踪，并确保产生对黏液清除有效的峰值流速。通过一系列对比实验，本文证实了自适应控制在减少振荡和超调方面的显著优势，能够更稳定、精确地调节气道压力。这种改进的控制策略不仅提高了临床安全性，还显著改善了治疗效果并降低了并发症风险。研究结果表明，采用自适应控制策略的改进型咳嗽辅助系统能够在辅助咳嗽过程中有效预防气道损伤，为患有咳痰障碍的重症患者提供了更安全、有效的痰液清除解决方案。
