CAJ | 학술논문

目的观察不同呼气阻力下正常人呼吸力学的改变,了解呼气阻力对人机同步性的影响.方法9例正常人在呼气阻力分别为0、5、10和15 cm H2O时进行呼气相阻力呼吸运动,观察膈肌肌电图(EMGdi)、胃内压(Pgas)、食管内压(Peso)、跨膈压(Pdi)、口腔压(Pm)和流量(Flow)的动态变化.结果(1) 随着阻力的增加,吸气相Peso和Pm的谷值(NPeso-in和NPm-in)逐渐减低,Pgas的峰值(PPgas-in)没有变化;而呼气相时,Peso、Pm和Pgas的峰值(PPeso-ex、PPm-ex和PPgas-ex)则逐渐增高.(2)吸气前,随着呼气阻力的增加,Peso、Pgas和Pm的基础压力(BPeso、BPgas和BPm)均逐渐升高.(3)在没有阻力或低阻力时,Peso、Pm和Pdi开始时间均迟于EMGdi.随着阻力的增加,这种差值逐渐减少,且在10和15 cm H2O时,Peso和Pm出现时间早于EMGdi;随着阻力的增加,Pgas和Flow出现时间均比EMGdi迟,且Pgas出现时间有延迟的倾向.(4)随着呼气阻力的增加,从吸气峰流速(FPeak-in)、75%峰流速(F75%Peak-in)和25%峰流速(F25%Peak-in)各时刻点与出现呼气流量时刻的时间差逐渐增加,而以Tdif[F25%(Peak-in)](F25%Peak-in时刻点与出现呼气流星时刻的时间差)的延长最明显,有统计学意义(P<005).结论存在呼气阻力时,吸气肌肉和呼气肌肉的活动均增强;当阻力较高时,腹肌的剧烈收缩将引起吸气前Peso和Pm升高,但没有影响吸气流速出现的时间;以峰流速的下降百分值作为吸气-呼气切换参数时,呼气阻力可引起呼气气流的延迟出现.
목적 관찰불동호기조력하정상인호흡역학적개변,료해호기조력대인궤동보성적영향.방법9례정상인재호기조력분별위0、5、10화15 cm H2O시진행호기상조력호흡운동,관찰격기기전도(EMGdi)、위내압(Pgas)、식관내압(Peso)、과격압(Pdi)、구강압(Pm)화류량(Flow)적동태변화.결과(1) 수착조력적증가,흡기상Peso화Pm적곡치(NPeso-in화NPm-in)축점감저,Pgas적봉치(PPgas-in)몰유변화;이호기상시,Peso、Pm화Pgas적봉치(PPeso-ex、PPm-ex화PPgas-ex)칙축점증고.(2)흡기전,수착호기조력적증가,Peso、Pgas화Pm적기출압력(BPeso、BPgas화BPm)균축점승고.(3)재몰유조력혹저조력시,Peso、Pm화Pdi개시시간균지우EMGdi.수착조력적증가,저충차치축점감소,차재10화15 cm H2O시,Peso화Pm출현시간조우EMGdi;수착조력적증가,Pgas화Flow출현시간균비EMGdi지,차Pgas출현시간유연지적경향.(4)수착호기조력적증가,종흡기봉류속(FPeak-in)、75%봉류속(F75%Peak-in)화25%봉류속(F25%Peak-in)각시각점여출현호기류량시각적시간차축점증가,이이Tdif[F25%(Peak-in)](F25%Peak-in시각점여출현호기류성시각적시간차)적연장최명현,유통계학의의(P<005).결론 존재호기조력시,흡기기육화호기기육적활동균증강;당조력교고시,복기적극렬수축장인기흡기전Peso화Pm승고,단몰유영향흡기류속출현적시간;이봉류속적하강백분치작위흡기-호기절환삼수시,호기조력가인기호기기류적연지출현.
Objective To observe the changes of respiratory mechanics of normal adults under the condition of expiratory load and investigate the effect of expiratory load on patient-ventilator synchronization.Methods Nine normal adults were asked to breath under the expiratory load of 0,5,10 and 15 cm H2O,and the diaphragmatic electromyography(EMGdi),gastral pressure(Pgas),esophageal pressure(Peso),mouth pressure(Pm),transdiaphramatic pressure(Pdi) and Flow were measured.Results (1)As the expiratory loading increased,the nadir of Peso and Pm became deeper,while the peak of Pgas did not increase during inspiration;and all the peak of Pgas,Peso and Pm increased during expiration. (2)As the expiratory loading increased,the basic pressure of Pgas,Peso and Pm just before the onset of inspiration increased. (3)The onset of Peso,Pm and Pdi was later than that of EMGdi in the condition of lower or no expiratory loading.As the expiratory loading increased,the time interval difference was decreased;and when the expiratory loading was 10 or 15 cm H2O,the onset of Peso and Pm was earlier than that of EMGdi. As the expiratory loading increased,the onset of Pgas and Flow was later than that of EMGdi and the time interval difference between Pgas and EMGdi tended to increase. (4)As the expiratory loading increased,the time from the peak of inspiratory Flow (Fpeak-in),F75%Peak-in or F25%Peak-in to the onset of expiration Flow increased and the changing of time interval difference between F25%Peak-in to the onset of expiration Flow increased much more(P<0.05).Conclusions Both the activity of inspiratory and expiratory muscle increase in the condition of expiratory loading. The expiratory loading may lead to the higher value of Peso and Pm just before the beginning of inspiration,but dose not delay the onset of Flow. Expiratory loading could lead to the delay of expiration.