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
Coronavirus disease 2019(COVID-19)caused by acute respiratory syndrome coronavirus 2(SARS-Cov-2)is still threatening the human life and society throughout the world.For those critically ill patients,mechanical ventila...Coronavirus disease 2019(COVID-19)caused by acute respiratory syndrome coronavirus 2(SARS-Cov-2)is still threatening the human life and society throughout the world.For those critically ill patients,mechanical ventilation(MV)is essential to provide life support during treatment.However,both the virus infection and MV disrupt the balance between secretion and elimination of airway mucus and lead to mucus accumulation in the lung.Postmortem examination verified that the lungs in patients died of COVID-19 are indeed filled with sticky mucus,suggesting a great need to improve airway mucus clearance in critically ill COVID-19 patients.Therefore,it may be helpful to comprehensively review the current understanding regarding the changes of biochemical and rheological features of airway mucus associated with the disease,as well as the physiological principles and algorithm to decide airway clearance techniques suitable for the critically ill COVID-19 patients.Based on these considerations,optimized strategies may be developed to eliminate the airway mucus accumulated in the airways of critically ill COVID-19 patients.展开更多
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
Objective To investigate the effects of 3-methyladenineon airway inflammation,airway hyperresponsivenessand mucus secretion in asthmatic mice,and to explore itsmechanism. Methods C57BL /6J female mice were randomlydiv...Objective To investigate the effects of 3-methyladenineon airway inflammation,airway hyperresponsivenessand mucus secretion in asthmatic mice,and to explore itsmechanism. Methods C57BL /6J female mice were randomlydivided into normal control group ( PBS),OVAgroup(OVA),OVA with 3-methyladenine group (OVA +3-MA),and OVA with 4-phenylbutyrate group (OVA +4-PBA). OVA group,OVA + 3-MA group and OVA + 4-PBA groups were all sensitized and challenged with OVAto establish asthmatic models,while PBS group was givenPBS as a control. At 2 h before challenge,OVA + 3-MAgroup was intraperitoneally injected with 3-methyladenine,and OVA + 4-PBA group was intraperitoneally injectedwith 4-phenylbutyrate. Airway hyperresponsiveness,eosinophils,and pathological changes of pulmonarytissue (hematoxylin-eosin,HE staining) were measuredto confirm the establishment of asthmatic models.展开更多
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supported by the Key Program of the NSF of China[No.11532003]the NSF of China[Nos.12072048,31670950]+1 种基金the Science and Technology Innovation Leading Plan of High Tech Industry in Hunan Province[2020SK2018]the Applied Basic Research Project of Changzhou[No.CJ20179039].
文摘Coronavirus disease 2019(COVID-19)caused by acute respiratory syndrome coronavirus 2(SARS-Cov-2)is still threatening the human life and society throughout the world.For those critically ill patients,mechanical ventilation(MV)is essential to provide life support during treatment.However,both the virus infection and MV disrupt the balance between secretion and elimination of airway mucus and lead to mucus accumulation in the lung.Postmortem examination verified that the lungs in patients died of COVID-19 are indeed filled with sticky mucus,suggesting a great need to improve airway mucus clearance in critically ill COVID-19 patients.Therefore,it may be helpful to comprehensively review the current understanding regarding the changes of biochemical and rheological features of airway mucus associated with the disease,as well as the physiological principles and algorithm to decide airway clearance techniques suitable for the critically ill COVID-19 patients.Based on these considerations,optimized strategies may be developed to eliminate the airway mucus accumulated in the airways of critically ill COVID-19 patients.
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Objective To investigate the effects of 3-methyladenineon airway inflammation,airway hyperresponsivenessand mucus secretion in asthmatic mice,and to explore itsmechanism. Methods C57BL /6J female mice were randomlydivided into normal control group ( PBS),OVAgroup(OVA),OVA with 3-methyladenine group (OVA +3-MA),and OVA with 4-phenylbutyrate group (OVA +4-PBA). OVA group,OVA + 3-MA group and OVA + 4-PBA groups were all sensitized and challenged with OVAto establish asthmatic models,while PBS group was givenPBS as a control. At 2 h before challenge,OVA + 3-MAgroup was intraperitoneally injected with 3-methyladenine,and OVA + 4-PBA group was intraperitoneally injectedwith 4-phenylbutyrate. Airway hyperresponsiveness,eosinophils,and pathological changes of pulmonarytissue (hematoxylin-eosin,HE staining) were measuredto confirm the establishment of asthmatic models.
