机械通气原理ppt课件

机械通气工作原理,1,主要内容,概述,参数测量/计算,运动方程,2,概述,3,4,5,O2,AIR,To Patient,50 psig,50 psig,BLENDER,RESERVOIR,10-15 PSIG,Air and O2 are mixed in a blender, stored as a mixed gas in a reservoir then pass through a single proportional valve.,PROPORTIONAL VALVE,Single Proportional System Hamilton Veolar, Bird 6400-8400st,6,O2,AIR,To Patient,50 psig,50 psig,Each gas has its own solenoid, flow sensor and pressure regulator . Both valves controlled by microprocessor.,FLOW SENSOR,FLOW SENSOR,Two Proportional Valve System NPB 7200-840, DRAGER E2-4, SERVO 300,7,O2,Pulmonetic LTV Turbine/Blender System,Blended gas to patient,Delivery Control Valve,Blower with Intragral Digital Blender,8,O2,AIR,50 psig,50 psig,Air and O2 solenoids combined with active exhalation valve.,PATIENT,EXH,Two Proportional Valve System With Active Exhalation Valve,9,PB-840,10,11,12,双比例电磁阀：精确调整氧浓度、流速和波形,13,低阻力主动呼气阀,14,低阻力主动呼气阀,15,安全阀,16,17,18,19,学习目的,掌握常见呼吸机的工作原理：气路、电路、及计算机控制技术 比较常见呼吸机的优缺点，了解未来呼吸机的发展方向及技术热点 设计研发全球领先的新一代Ventilator，代号：协作一号,20,这显然是不可能的,学习目的,21,学习目的,对机械通气原理有一个大致的了解！,22,23,概念,呼吸 外呼吸 气体在血液中的运输 内呼吸,24,概念,呼吸 外呼吸 通气 弥散 气体在血液中的运输 内呼吸,25,概念,通气,26,27,压差是气体运动的动力,P1,P2,R,28,-5,0,0,Normal Respiration End-Expiration,29,-10,0,-5,Normal Respiration Inspiration,30,-10 to -5,0,Normal Respiration Expiration,31,吸气,Pb,Pa,Pa Pa 机械通气,32,自主呼吸,胸廓容量改变,气流,压差,33,机械通气,压差,容量变化,气流,34,机械通气,机器产生压差,容量变化,气流,35,概念,通气机 用来辅助或替代呼吸肌工作的机器,36,概念,机械通气 使用通气机驱动气体进出呼吸系统,37,机械通气 负压通气 正压通气,概念,38,机械通气 负压通气 正压通气,概念,39,40,41,Iron lung polio ward at Rancho Los Amigos Hospital in 1953.,42,43,44,机械通气 负压通气 正压通气,概念,45,机械通气 负压通气 正压通气,概念,46,47,48,49,概念,通气 机械通气 正压通气,50,51,52,53,54,55,概念,正压通气 容量控制 压力控制,56,Volume 500 ml,Volume 500 ml,57,Pressure 20 cm H2O,Pressure 20 cm H2O,58,59,Pressure 3500 cm H20,Pressure 35 cm H20 Tidal volume 500 ml,60,Microprocessor Control,Pressure 3500 cm H20,solenoid,Microprocessor,exhale valve,Tidal volume 500 ml Pressure 35 cm H20,61,描述气体运动参数,压力 流速 时间 容量,62,参数测量/计算,63,监测参数,测量参数 计算参数,64,测量参数,压力 流速 时间,65,计算参数,容量 顺应性 阻力,66,管道 + 气球 模型,67,Tube + Spring Model,弹性阻力,摩擦阻力,68,Y型管 通气机内部 食道,压力测定部位,69,压力测定部位,70,压力测定部位,71,流速测定方法,压差传感器 热线型传感器 超声传感器,72,流速测定方法,压差传感器,73,流速测定方法,温差传感器,74,Flow Sensor,75,76,Heated Wire Anemometer,77,Broken wire,78,流速测定方法,温差传感器（热线型传感器）,晶体热膜式流量传感器,79,超声流量传感器,流速测定方法,80,流速测定方法,超声流量传感器,81,流速测定方法,超声流量传感器,82,流速测定部位,Y型管 通气机内部,83,流速测定部位,Y型管,84,流速测定部位,通气机内部,85,测量参数,压力 流速 时间,86,计算参数,容量 顺应性 阻力,87,容量计算,88,容量,流速,时间,容量计算,容量 = 流速 时间,89,容量计算,气体容量与压力、温度和水蒸气含量密切相关 BTPS Body Temperature Pressure Saturated (In the lungs of the patient),90,Some easy principles of physics (i),What happens if you heat a certain gas Volume?,The initial volume of gas increases 1L of gas at 20C increases to 1.058 L at 37C while the pressure level remains the same,91,The initial volume of gas increases up to the saturation point of water 1L of dried gas at 20C increases to 1.023 L if humidified to 100% where 2.3% of the gas mixture is water vapor,Some easy principles of physics (ii),What happens if you humidify dried gas?,92,The initial volume of gas decreases proportionally to the applied pressure 1L of gas at 1013 mbar will decrease to 980mL if an additional pressure of 20mbar is applied,Some easy principles of physics (iii),What happens if you humidify dried gas?,93,P ressure,S aturated,1000,mL,37 C, 100 % RH,N ormal,T emperature,P ressure,S aturated,930,mL,20 C, 100 % RH,容量测定,94,容量测定,95,C =,D V,D P,静态顺应性,96,静态顺应性,流速为零时测定（指令通气 + 吸气暂停） 受患者体位和肌肉松弛程度等影响,97,静态顺应性,500,15-5,= 50 ml/cmH20,Compliance =,Vte,Plateau - PEEP,Plateau Pressure 15 cm,PIP 20 cm,VTE 500 cc,Peak Flow = 60 L/min,Peak Flow = 60 L/min,Plateau Pressure 15 cm,PIP 20 cm,VTE 500 cc,98,内源性PEEP的存在造成顺应性计算值偏低,VTE 500 cc,P,T,Plateau = 20,PEEP = 5,Lung PEEP = 10,静态顺应性,99,R =,D P,D F,气道阻力,100,Plateau Pressure 15 cm,PIP 20 cm,VTE 500 cc,Peak Flow = 60 L/min,Resistance =,PIP - Plateau,Peak Flow,Resistance =,20 - 15,1 L / sec,= 5 cmH20 / L / sec,气道阻力,101,102,呼气,吸气,通气,概念,103,机械通气工作原理,吸气由什么触发 Trigger 吸气相通气机限制什么 Limit 吸气相什么时候结束 Cycle 呼气相预设压力 Baseline,104,机械通气工作原理,A Trigger B Limit C Cycle D Baseline,A,B,C,D,105,机械通气工作原理,吸气由什么触发（Trigger）？ 患者（压力/流速/容量/胸部阻抗/腹部活动） 通气机（时间） 操作者,106,吸气相通气机限制什么（Limit）？ 流速 压力,机械通气工作原理,107,吸气相什么时候结束（ Cycle）？ 流速 压力 时间 容量,机械通气工作原理,108,机械通气工作原理,109,容量控制与压力控制通气,机械通气工作原理,110,Comparison chart,111,运动方程,112,描述气体运动参数,压力 流速 时间 容量,113,描述肺部情况基本参数,114,运动方程,压力、流速、容量、时间与顺应性、阻力之间的关系？,115,ventilation pressure to deliver tidal volume,=,elastic pressure to inflate lungs and chest wall,+,resistive pressure to make air flow through the airways,Pmus Pvent = EV Rf = 1/CV Rf,Pmus Pvent = Pelastic Presistive,Equation of Motion,116,运动方程,通气驱动压 = 弹性回缩压流速阻力压 =容量弹力流速阻力 =容量/顺应性流速阻力,117,运动方程,容量控制方波,118,运动方程,容量控制方波,119,运动方程,压力控制,120,运动方程,通气驱动压 = 呼吸肌产生负压 通气机产生正压,stiff lung,mus = - 25 mbar,V,t = 500 ml,+20 mbar,C = 20 ml / mbar,E = 50 mbar / L,P,mus = - 5 mbar,V,t = 500 ml,121,呼吸肌产生负压与通气机产生正压是等效的,122,主要内容,概述,参数测量/计算,运动方程,123,正压通气工作原理,124,谢谢,125,