Secretions in the airways of ventilated patients must be cleared efficiently and timely. A novel ventilator(SC ventilator) is proposed with an automatic secretion clearance function in order to provide a new approach....Secretions in the airways of ventilated patients must be cleared efficiently and timely. A novel ventilator(SC ventilator) is proposed with an automatic secretion clearance function in order to provide a new approach. A mathematical model of a ventilation system with the SC ventilator is set up to optimize the SC ventilator. Based on the research, conclusion can be reached as follows. First, the experimental results and the mathematical model are proved to be authentic and reliable. Second, the secretion clearance efficiency of the SC ventilator may be higher than that of IL-IE device. Finally, increasing the inspiratory positive airway pressure or decreasing the expiatory positive airway pressure of the SC ventilator can improve the efficiency of the secretion clearance. This paper lays a foundation for the secretion clearance improvement of the SC ventilator.展开更多
[目的]系统评价咳痰机在机械通气病人呼吸道清理中的应用效果。[方法]手动检索中国和美国临床试验注册中心官网,计算机检索PubMed、Web of Science、Cochrane Library、EMBASE、CBM、中国知网和万方数据库,收集建库至2018年1月关于采用...[目的]系统评价咳痰机在机械通气病人呼吸道清理中的应用效果。[方法]手动检索中国和美国临床试验注册中心官网,计算机检索PubMed、Web of Science、Cochrane Library、EMBASE、CBM、中国知网和万方数据库,收集建库至2018年1月关于采用咳痰机清理机械通气病人呼吸道的随机对照试验。由2名研究者根据纳入及排除标准筛选文献并提取资料,依据Cochrane Handbook评价文献质量,使用Stata12.0软件进行Meta分析或仅做描述性分析。[结果]共纳入6项随机对照试验。描述性分析结果显示:干预组医院感染情况及肺部感染情况优于对照组,低氧血症发生率低于对照组,氧分压值高于对照组,二氧化碳分压值低于对照组,降钙素原、通气失败率及再插管率低于对照组(P<0.05)。Meta分析结果显示:干预组病人氧合指数[SMD=1.88,95%CI(0.79,2.97),P=0.001]、肺顺应性[SMD=0.95,95%CI(0.65,1.25),P=0.00]优于对照组,机械通气时间短于对照组[SMD=-2.21,95%CI(-3.74,-0.67),P=0.005]。[结论]现有证据表明:咳痰机能有效协助机械通气病人清除呼吸道分泌物,改善机体氧合及肺顺应性,缩短病人机械通气时间,促进病人恢复。展开更多
随着肺移植技术的日趋成熟,肺移植术成为治疗终末期肺疾病的唯一方法。术后感染是肺移植术后最常见的并发症和致死因素。气道分泌物的有效清除能够减少术后感染、肺不张等并发症,促进患者早期康复。本综述分析肺移植患者不同分泌物清除...随着肺移植技术的日趋成熟,肺移植术成为治疗终末期肺疾病的唯一方法。术后感染是肺移植术后最常见的并发症和致死因素。气道分泌物的有效清除能够减少术后感染、肺不张等并发症,促进患者早期康复。本综述分析肺移植患者不同分泌物清除策略的优缺点及可行性,提出肺移植不同时期综合优化的分泌物清除策略。利用中国知网、万方、PubMed、Web of Science中英文数据库,以'肺移植''分泌物清除''排痰''物理治疗'为关键词,检索2008-01-2018-12相关文献。纳入标准:肺移植术后。剔除标准:(1)综述类文献;(2)研究资料缺失或质量较差。最终45篇文献纳入分析。现代医学的机械排痰法、气道廓清技术和运动对气道分泌物清除均有不同效果;传统中医的中药、针灸和推拿对肺移植术后排痰也有积极意义。在肺移植术不同阶段,个性化综合优化的分泌物清除策略对患者康复至关重要。展开更多
A pressure controlled mechanical ventilator with an automatic secretion clearance function can improve secretion clearance safely and efficiently.Studies on secretion clearance by pressure controlled systems show that...A pressure controlled mechanical ventilator with an automatic secretion clearance function can improve secretion clearance safely and efficiently.Studies on secretion clearance by pressure controlled systems show that these are suited for clinical applications.However,these studies are based on a single lung electric model and neglect the coupling between the two lungs.The research methods applied are too complex for the analysis of a multi-parameter system.In order to understand the functioning of the human respiratory system,this paper develops a dimensionless mathematical model of doublelung mechanical ventilation system with a secretion clearance function.An experiment is designed to verify the mathematical model through comparison of dimensionless experimental data and dimensionless simulation data.Finally,the coupling between the two lungs is studied,and an orthogonal experiment designed to identify the impact of each parameter on the system.展开更多
Cough is a defensive behavior that protects the respiratory system from infection and clears airway secretions.Cough airflow dynamics have been analyzed by a variety of mathematical and experimental tools.In this pape...Cough is a defensive behavior that protects the respiratory system from infection and clears airway secretions.Cough airflow dynamics have been analyzed by a variety of mathematical and experimental tools.In this paper,the cough airflow dynamics of 42 subjects were obtained and analyzed.An identification model based on piecewise Gauss function for cough airflow dynamics is proposed through the dimensionless method,which could achieve over 90%identification accuracy.Meanwhile,an assisted cough system based on pneumatic flow servo system is presented.The vacuum situation and feedback control are used to increase the simulated peak cough flow rate,which are important for airway secretion clearance and to avoid airway collapse,respectively.The simulated cough peak flow could reach 5 L/s without the external assistance such as manual pressing,patient cooperation and other means.Finally,the backstepping control is developed to generate a simulated cough airflow that closely mimics the natural cough airflow of humans.The assisted cough system opens up wide opportunities of practical application in airway secretion clearance for critically ill patients with COVID 2019 and other pulmonary diseases.展开更多
文摘Secretions in the airways of ventilated patients must be cleared efficiently and timely. A novel ventilator(SC ventilator) is proposed with an automatic secretion clearance function in order to provide a new approach. A mathematical model of a ventilation system with the SC ventilator is set up to optimize the SC ventilator. Based on the research, conclusion can be reached as follows. First, the experimental results and the mathematical model are proved to be authentic and reliable. Second, the secretion clearance efficiency of the SC ventilator may be higher than that of IL-IE device. Finally, increasing the inspiratory positive airway pressure or decreasing the expiatory positive airway pressure of the SC ventilator can improve the efficiency of the secretion clearance. This paper lays a foundation for the secretion clearance improvement of the SC ventilator.
文摘[目的]系统评价咳痰机在机械通气病人呼吸道清理中的应用效果。[方法]手动检索中国和美国临床试验注册中心官网,计算机检索PubMed、Web of Science、Cochrane Library、EMBASE、CBM、中国知网和万方数据库,收集建库至2018年1月关于采用咳痰机清理机械通气病人呼吸道的随机对照试验。由2名研究者根据纳入及排除标准筛选文献并提取资料,依据Cochrane Handbook评价文献质量,使用Stata12.0软件进行Meta分析或仅做描述性分析。[结果]共纳入6项随机对照试验。描述性分析结果显示:干预组医院感染情况及肺部感染情况优于对照组,低氧血症发生率低于对照组,氧分压值高于对照组,二氧化碳分压值低于对照组,降钙素原、通气失败率及再插管率低于对照组(P<0.05)。Meta分析结果显示:干预组病人氧合指数[SMD=1.88,95%CI(0.79,2.97),P=0.001]、肺顺应性[SMD=0.95,95%CI(0.65,1.25),P=0.00]优于对照组,机械通气时间短于对照组[SMD=-2.21,95%CI(-3.74,-0.67),P=0.005]。[结论]现有证据表明:咳痰机能有效协助机械通气病人清除呼吸道分泌物,改善机体氧合及肺顺应性,缩短病人机械通气时间,促进病人恢复。
文摘随着肺移植技术的日趋成熟,肺移植术成为治疗终末期肺疾病的唯一方法。术后感染是肺移植术后最常见的并发症和致死因素。气道分泌物的有效清除能够减少术后感染、肺不张等并发症,促进患者早期康复。本综述分析肺移植患者不同分泌物清除策略的优缺点及可行性,提出肺移植不同时期综合优化的分泌物清除策略。利用中国知网、万方、PubMed、Web of Science中英文数据库,以'肺移植''分泌物清除''排痰''物理治疗'为关键词,检索2008-01-2018-12相关文献。纳入标准:肺移植术后。剔除标准:(1)综述类文献;(2)研究资料缺失或质量较差。最终45篇文献纳入分析。现代医学的机械排痰法、气道廓清技术和运动对气道分泌物清除均有不同效果;传统中医的中药、针灸和推拿对肺移植术后排痰也有积极意义。在肺移植术不同阶段,个性化综合优化的分泌物清除策略对患者康复至关重要。
文摘A pressure controlled mechanical ventilator with an automatic secretion clearance function can improve secretion clearance safely and efficiently.Studies on secretion clearance by pressure controlled systems show that these are suited for clinical applications.However,these studies are based on a single lung electric model and neglect the coupling between the two lungs.The research methods applied are too complex for the analysis of a multi-parameter system.In order to understand the functioning of the human respiratory system,this paper develops a dimensionless mathematical model of doublelung mechanical ventilation system with a secretion clearance function.An experiment is designed to verify the mathematical model through comparison of dimensionless experimental data and dimensionless simulation data.Finally,the coupling between the two lungs is studied,and an orthogonal experiment designed to identify the impact of each parameter on the system.
基金The research is supported by the National Natural Science Foundation of China(No.52005015)the China Postdoctoral Science Foundation(No.2019M660391)+2 种基金the Open Foundation of the State Key Laboratory of Fluid Power and Mechatronic Systems(No.GZKF-201920)the Outstanding Young Scientists in Beijing(No.BJJWZYJH01201910006021)the National Key Research and Development Project(No.2019YFC0121702).
文摘Cough is a defensive behavior that protects the respiratory system from infection and clears airway secretions.Cough airflow dynamics have been analyzed by a variety of mathematical and experimental tools.In this paper,the cough airflow dynamics of 42 subjects were obtained and analyzed.An identification model based on piecewise Gauss function for cough airflow dynamics is proposed through the dimensionless method,which could achieve over 90%identification accuracy.Meanwhile,an assisted cough system based on pneumatic flow servo system is presented.The vacuum situation and feedback control are used to increase the simulated peak cough flow rate,which are important for airway secretion clearance and to avoid airway collapse,respectively.The simulated cough peak flow could reach 5 L/s without the external assistance such as manual pressing,patient cooperation and other means.Finally,the backstepping control is developed to generate a simulated cough airflow that closely mimics the natural cough airflow of humans.The assisted cough system opens up wide opportunities of practical application in airway secretion clearance for critically ill patients with COVID 2019 and other pulmonary diseases.
