机械通气患者的压力容积曲线学习课件

1、机械通气患者的压力容积曲线机械通气患者的压力容积曲线 呼吸系统压力容积曲线呼吸系统压力容积曲线 反映肺和胸廓的静态机械力学特征 了解患者的病理生理学改变 设置机械通气参数 静态法(static method)准静态法(quasistatic) 超大注射器法(super-syringe technique) 吸气阻断法(inspiratory occlusion technique) 低流量法(continuous inflation at a constant flow) PV曲线的测定方法曲线的测定方法 静态静态PV曲线的测定方法曲线的测定方法(I): 超大注射器法超大注射器法 测定前的准备

2、工作 镇静+肌松 测定前15分钟预氧合 FiO2 1.0 PEEP 0 准备好1.5或3.0 L超大注射器 充满经过湿化的氧气 Matamis D, Lemaire F, Harf A, et al: Total respiratory pressure volume curves in the adult respiratory distress syndrome. Chest 1984; 86: 58-66 静态静态PV曲线的测定方法曲线的测定方法(I): 超大注射器法超大注射器法 Matamis D, Lemaire F, Harf A, et al: Total respiratory

3、 pressure volume curves in the adult respiratory distress syndrome. Chest 1984; 86: 58-66 静态静态PV曲线的测定方法曲线的测定方法(I): 超大注射器法超大注射器法 将患者脱离呼吸机数秒钟 使得肺完全排空，恢复至FRC 将超大注射器连接气管插管 从FRC开始进行充气 每次向肺内注入50 100 mL气体 等待3秒钟以使压力稳定 通过压力传感器测定气道压力 再次充气50 100 mL 直至Paw达到40 50 cmH2O，或注入气体达到1.5 L 整个过程通常不超过90秒钟 Matamis D, Lemai

4、re F, Harf A, et al: Total respiratory pressure volume curves in the adult respiratory distress syndrome. Chest 1984; 86: 58-66 静态静态PV曲线的测定方法曲线的测定方法(I): 超大注射器法超大注射器法 Matamis D, Lemaire F, Harf A, et al: Total respiratory pressure volume curves in the adult respiratory distress syndrome. Chest 1984;

5、86: 58-66 静态静态PV曲线的测定方法曲线的测定方法(I): 超大注射器法超大注射器法 Matamis D, Lemaire F, Harf A, et al: Total respiratory pressure volume curves in the adult respiratory distress syndrome. Chest 1984; 86: 58-66 通常重复测定4次 第1次结果舍弃 对volume history进行校正 后3次结果取平均值 优点缺点 测定PV曲线的经典方法 1980s的金标准 可以测定吸气支及呼气支PV曲线 测定时须脱离呼吸机 充气过程中肺容积

6、减少 充气过程延长( 45 s) 消耗氧气导致肺容积减少 仅部分被生成的CO2代偿 注射器中氧气的温度和湿度影响测定 结果 使用未经加温加湿的气体导致曲 线左移 静态静态PV曲线的测定方法曲线的测定方法(I): 超大注射器法超大注射器法 Lu Q, Rouby JJ. Measurement of pressure-volume curves in patients on mechanical ventilation: methods and significance. Crit Care 2000; 4: 91-100 静态静态PV曲线的测定方法曲线的测定方法(II): 吸气阻断法吸气阻断法

7、 Levy P, Similowski T, Corbeil C, et al: A method for studying the static volume-pressure curves of the respiratory system during mechanical ventilation. J Crit Care 1989, 4: 83-89 测定原理 吸气末平台压力反映肺泡压力 使用不同潮气量可以得到相应的 肺泡压力 静态静态PV曲线的测定方法曲线的测定方法(II): 吸气阻断法吸气阻断法 Levy P, Similowski T, Corbeil C, et al: A m

8、ethod for studying the static volume-pressure curves of the respiratory system during mechanical ventilation. J Crit Care 1989, 4: 83-89 测定前的准备工作 镇静+肌松 呼吸机须具备的功能 吸气末暂停 呼气末暂停 平台压及呼气末压力显示 设置基础通气模式 容量控制通气模式 恒定流量 校正volume history 静态静态PV曲线的测定方法曲线的测定方法(II): 吸气阻断法吸气阻断法 Levy P, Similowski T, Corbeil C, et a

9、l: A method for studying the static volume-pressure curves of the respiratory system during mechanical ventilation. J Crit Care 1989, 4: 83-89 每次测定平台压力前应当 恢复基础通气模式及设置 使用呼气末暂停测定PEEPi 保证肺容积及呼气末压力恒定(volume history) 每次测定时改变潮气量 通过改变呼吸频率即吸气时间增加或减少潮气量 保持吸气流量不变 随机选择潮气量 吸气末阻断数秒钟后测定平台压力 得到不同潮气量所对应的肺泡压力并作图 静态静

10、态PV曲线的测定方法曲线的测定方法(II): 吸气阻断法吸气阻断法 Barberis L, Manno E, Guerin C. Effect of end-inspiratory pause duration on plateau pressure in mechanically ventilated patients. Intensive Care Med 2003; 29: 130-134 静态静态PV曲线的测定方法曲线的测定方法(II): 吸气阻断法吸气阻断法 Barberis L, Manno E, Guerin C. Effect of end-inspiratory pause

11、duration on plateau pressure in mechanically ventilated patients. Intensive Care Med 2003; 29: 130-134 静态静态PV曲线的测定方法曲线的测定方法(II): 吸气阻断法吸气阻断法 Barberis L, Manno E, Guerin C. Effect of end-inspiratory pause duration on plateau pressure in mechanically ventilated patients. Intensive Care Med 2003; 29: 13

12、0-134 Volume history对对PV曲线测定的影响曲线测定的影响 Takeuchi M, Sedeek KA, Schettino GPP, et al. Peak pressure during volume history and pressure-volume curve measurement affects analysis. Am J Respir Crit Care Med 2001; 164: 1225-1230 Volume history对对PV曲线测定的影响曲线测定的影响 Nishida T, Suchodolski K, Schettino GPP, et

13、al. Peak volume history and peak pressure-volume curve pressures independently affect the shape of the pressure-volume curve of the respiratory system. Crit Care Med 2004; 32: 1358-1364 Volume history对对PV曲线测定的影响曲线测定的影响 Nishida T, Suchodolski K, Schettino GPP, et al. Peak volume history and peak pres

14、sure-volume curve pressures independently affect the shape of the pressure-volume curve of the respiratory system. Crit Care Med 2004; 32: 1358-1364 Volume history对对PV曲线测定的影响曲线测定的影响 Nishida T, Suchodolski K, Schettino GPP, et al. Peak volume history and peak pressure-volume curve pressures independe

15、ntly affect the shape of the pressure-volume curve of the respiratory system. Crit Care Med 2004; 32: 1358-1364 优点缺点 患者无需脱离呼吸机 可以忽略氧气消耗 每次测定仅3秒钟 可以在不同PEEP下测定PV曲线 所有呼吸机均可使用 耗时较长(约15分钟) 恢复基础通气设置 测定PEEPi 不能测定呼气支PV曲线 静态静态PV曲线的测定方法曲线的测定方法(II): 吸气阻断法吸气阻断法 Lu Q, Rouby JJ. Measurement of pressure-volume cur

16、ves in patients on mechanical ventilation: methods and significance. Crit Care 2000; 4: 91-100 准静态准静态PV曲线的测定方法曲线的测定方法(I): 低流量法低流量法 测定原理: 顺应性计算公式 Compliance volume presssure Compliance volume/time presssure/time 准静态准静态PV曲线的测定方法曲线的测定方法(I): 低流量法低流量法 测定原理: 顺应性计算公式 Compliance V presssure/time 若V(t)恒定 则克服

17、阻力的压力差恒定 此时气道压力与呼吸系统顺应性呈负相关 准静态准静态PV曲线的测定方法曲线的测定方法(I): 低流量法低流量法 低流量法测定PV曲线: 历史演变 Suratt et al (JAP 1980; Chest 1981) 吸气流量0.60 0.10 (0.40 0.65) L/sec PV曲线的顺应性与静态法相同 Ranieri et al (Am J Respir Crit Care Med 1994) 低流量法PV曲线有助于确定PEEP导致的肺泡复张及过度膨胀 Servillo et al (Am J Respir Crit Care Med 1997); Lu et al (

18、Am J Respir Crit Care Med 1999) 吸气流量20 60 lpm时, PV曲线斜率测定准确, 但高估UIP和LIP 准静态准静态PV曲线的测定方法曲线的测定方法(I): 低流量法低流量法 Suratt PM, Owens DH, Kilgore WT, Harry RR, Hsiao HS: A pulse method of measuring respiratory system compliance. J Appl Physiol 1980, 49: 1116-1121 Suratt PM, Owens DH: A pulse method of measuri

19、ng respiratory system compliance in ventilated patients. Chest 1981, 80: 34-38 Ranieri VM, Giuliani R, Flore T, Dambrosio M, Milic-Emili J: Volumepressure curve of the respiratory system predicts effects of PEEP in ARDS: occlusion versus constant flow technique. Am J Respir Crit Care Med 1994, 149:

20、19-27 Servillo G, Svantesson C, Beydon L, et al: Pressurevolume curves in acute respiratory failure. Automated low flow inflation versus occlusion. Am J Respir Crit Care Med 1997, 155: 1629-1636 Lu Q, Vieira S, Richecoeur J, et al: A simple automated method for measuring pressure-volume curve during

21、 mechanical ventilation. Am J Respir Crit Care Med 1999, 159: 275-282 准静态准静态PV曲线的测定方法曲线的测定方法(I): 低流量法低流量法 低流量法测定PV曲线: 历史演变 Mankikian et al (Crit Care med 1983) 吸气流量1.7 lpm 准静态PV曲线与静态法(超大注射器法)相同 吸气时间长达60 s Servillo et al (Am J Respir Crit Care Med 1997); 吸气流量15 lpm时, 准静态PV曲线右移, 但斜率不变 高估UIP和LIP Mankik

22、ian B, Lemaire F, Benito S, et al: A new device for measurement of pulmonary pressure-volume curves in patients on mechanical ventilation. Crit Care Med 1983； 11: 897-901 Servillo G, Svantesson C, Beydon L, et al: Pressurevolume curves in acute respiratory failure. Automated low flow inflation versu

23、s occlusion. Am J Respir Crit Care Med 1997, 155: 1629-163 准静态准静态PV曲线的测定方法曲线的测定方法(I): 低流量法低流量法 减去克服气道阻力所需压力减去克服气道阻力所需压力进一步降低吸气流量进一步降低吸气流量 Ptot = Ptrach + Pres(tube) Ptrach = Pel + Pres 与吸气阻断法相比 呼吸系统顺应性, UIP和LIP均相同 Paw = Pressure + Pel Pressure = Flow x Raw 当吸气流量0 Pressure 0 Paw Pel 如何提高准静态PV曲线的准确性 S

24、ervillo G, Svantesson C, Beydon L, et al: Pressurevolume curves in acute respiratory failure. Automated low flow inflation versus occlusion. Am J Respir Crit Care Med 1997, 155: 1629-1636 Lu Q, Vieira S, Richecoeur J, et al: A simple automated method for measuring pressure-volume curve during mechan

25、ical ventilation. Am J Respir Crit Care Med 1999, 159: 275-282 准静态准静态PV曲线的测定方法曲线的测定方法(I): 低流量法低流量法 Jonson B, Richard JC, Straus C, et al: Pressurevolume curves and compliance in acute lung injury. Am J Respir Crit Care Med 1999, 159: 1172-1178 准静态准静态PV曲线的测定方法曲线的测定方法(I): 低流量法低流量法 Krason S, Sndergaard

26、 S, Lundin S, Wiklund J, Stenqvist O. Evaluation of pressure/volume loops based on intratracheal pressure measurements during dynamic conditions. Acta Anaesthesiol Scand 2000; 44: 571-577 准静态准静态PV曲线的测定方法曲线的测定方法(I): 低流量法低流量法 减去克服气道阻力所需压力减去克服气道阻力所需压力进一步降低吸气流量进一步降低吸气流量 Ptot = Ptrach + Pres(tube) Ptrach

27、 = Pel + Pres 与吸气阻断法相比 呼吸系统顺应性, UIP和LIP均相同 Paw = Pressure + Pel Pressure = Flow x Raw 当吸气流量0 Pressure 0 Paw Pel 如何提高准静态PV曲线的准确性 Servillo G, Svantesson C, Beydon L, et al: Pressurevolume curves in acute respiratory failure. Automated low flow inflation versus occlusion. Am J Respir Crit Care Med 1997

28、, 155: 1629-1636 Lu Q, Vieira S, Richecoeur J, et al: A simple automated method for measuring pressure-volume curve during mechanical ventilation. Am J Respir Crit Care Med 1999, 159: 275-282 准静态准静态PV曲线的测定方法曲线的测定方法(I): 低流量法低流量法 Lu Q, Vieira S, Richecoeur J, et al: A simple automated method for measu

29、ring pressure-volume curve during mechanical ventilation. Am J Respir Crit Care Med 1999, 159: 275-282 呼吸机设置 容量控制通气模式 吸气流量恒定 呼吸频率5 lpm I:E4:1 VtFlow 设置1500 mL3 lpm 设置21500 mL9 lpm 准静态准静态PV曲线的测定方法曲线的测定方法(I): 低流量法低流量法 Lu Q, Vieira S, Richecoeur J, et al: A simple automated method for measuring pressur

30、e-volume curve during mechanical ventilation. Am J Respir Crit Care Med 1999, 159: 275-282 准静态准静态PV曲线的测定方法曲线的测定方法(I): 低流量法低流量法 Lu Q, Vieira S, Richecoeur J, et al: A simple automated method for measuring pressure-volume curve during mechanical ventilation. Am J Respir Crit Care Med 1999, 159: 275-28

31、2 PEEPi 呼气流量从呼气末数值 下降至0 克服气道阻力所需压力 (Pres): 吸气流量开始恒 定时所对应的气道压力 与PEEPi的差值 吸气流量开始恒定 LIP: 初始阶段顺应性曲 线与PV曲线斜率的交点 准静态准静态PV曲线的测定方法曲线的测定方法(I): 低流量法低流量法 Lu Q, Vieira S, Richecoeur J, et al: A simple automated method for measuring pressure-volume curve during mechanical ventilation. Am J Respir Crit Care Med 1

32、999, 159: 275-282 当吸气流量设置为9 lpm时 PV曲线因阻力因素的影响向 右侧移动 高估LIP (统计学无差异) PV曲线斜率无差异 优点缺点 患者无需脱离呼吸机 不影响肺容积 测定时间较短 每次测定仅需10秒钟 整个操作包括曲线分析仅需2分 钟 可以在不同PEEP下测定PV曲线 需要特殊的呼吸机 吸气流量较高时影响准确性 PV曲线右移 不能测定呼气支PV曲线 准静态准静态PV曲线的测定方法曲线的测定方法(I): 低流量法低流量法 Lu Q, Rouby JJ. Measurement of pressure-volume curves in patients on mec

33、hanical ventilation: methods and significance. Crit Care 2000; 4: 91-100 Draeger Evita XLHamilton Galileo Gold/G5 低流量法 吸气支和呼气支PV曲线 改良低流量法 压力改变速度很慢 吸气支和呼气支PV曲线 准静态准静态PV曲线的测定方法曲线的测定方法(II): 改改良良低流量法低流量法 准静态准静态PV曲线的测定方法曲线的测定方法(II): 改改良良低流量法低流量法 /./PN%20689213_PV-Tool_WP_01-

34、Validation_of_New_Method.pdf Piacentini E, Wysocki M, Blanch L. A new automated method versus continuous positive airway pressure method for measuring pressure-volume curves in patients with acute lung injury. Intensive Care Med 2009; 35: 565-570 Hamilton Galileo Gold采用的改良低流量法 测定吸气与呼气PV曲线 与CPAP方法相同

35、与低流量法相同 低流量低流量: How Low is Low? 目的: 评价不同吸气流量下测 定的准静态PV曲线, 其LIP, UIP, 最大斜率及WOB是否存 在差异 研究对象: 7名接受机械通气的 ARDS患者 方法: 容量控制通气模式 吸气流量1, 2, 5, 10 lpm 吸气时间从73 1.6 sec到 8.8 0.69 sec 结论: LIP无差异 UIP和顺应性有统计学差异 Gama AM, Meyer EC, Gaudencio AM, et al. Different low constant flows can equally determine the lower inf

36、ection point in acute respiratory distress syndrome patients. Artif Organs 2001; 25: 882-889 低流量低流量: How Low is Low? Figure 1. Effect of inspiratory flow on airway pressure traces. The curve on the left was obtained by using a 30 L/min flow, the curve on the right with 6 L/min. The component related

37、 to the resistance of flow through airways and tracheal cannula (P1 = Pmax Pi) increases with higher flows, whereas the component related to the viscoelastic properties of lung parenchyma (P2 = Pi Pplat) remains constant in both tracings. The goal in the low-flow technique for acquisition of PV curv

38、es is to use a flow that makes P1 negligible. Paw = airway pressure, Pmax = maximum airway pressure, Pi = pressure at the beginning of the inspiratory pause, Pplat = plateau pressure or pressure at the end of the inspiratory pause. Bensenor FE, Vieira JE, Auler JOC. Guidelines for inspiratory flow s

39、etting when measuring the pressure-volume relationship. Anesth Analg 2003; 97: 145-150 低流量低流量: How Low is Low? Bensenor FE, Vieira JE, Auler JOC. Guidelines for inspiratory flow setting when measuring the pressure-volume relationship. Anesth Analg 2003; 97: 145-150 低流量低流量: How Low is Low? Bensenor F

40、E, Vieira JE, Auler JOC. Guidelines for inspiratory flow setting when measuring the pressure-volume relationship. Anesth Analg 2003; 97: 145-150 低流量低流量: How Low is Low? Bensenor FE, Vieira JE, Auler JOC. Guidelines for inspiratory flow setting when measuring the pressure-volume relationship. Anesth

41、Analg 2003; 97: 145-150 呼吸系统静态呼吸系统静态PV曲线曲线: What Else? (B) The tracheal pressure Ptrach (inner loop, dashed area) is calculated point by point. The pressure difference between the outer PAW/V-loop and the inner Ptrach/V-loop mainly represents the flow-dependent resistive pressure drop across the ETT

42、. The Ptrach/V- loop is subdivided into eight slices (indicated by horizontal lines) and respiratory mechanics are analysed separately for each slice. The upper and lower 5% of the tidal volume (VT) (i.e. slices 1 and 8, respectively) are excluded from analysis. The remaining 90% of VT are divided i

43、nto 6 slices. One volume-dependent dynamic compliance and resistance of the respiratory system (Cr s,dyn and Rr s,dyn) are calculated per slice. (C) Quality check: Ptrach is recalculated point by point for each slice, using the calculated values for Cr s,dyn and Rr s,dyn and the measured volume and

44、flow. This recalculated Ptrach/V-loop is superimposed on the measured Ptrach/V-loop, and the pressure difference between both loops reflects the accuracy of the calculated mechanical parameters. The measured and recalculated loops in C are barely distinguishable. Paw-Volume Curve Lichtwarck-Aschoff

45、M, Kessler V, Sjostrand UH, et al. Static versus dynamic respiratory mechanics for setting the ventilator. Br J Anaesth 2000; 85: 577-586 呼吸系统静态呼吸系统静态PV曲线曲线: What Else? 多元线性回归模型(multiple linear regression model) Paw = Vt/Crs,st + Rrs x V + PEEPtot 多元非线性回归模型(multiple nonlinear regression model) Paw =

46、 Vt/Crs,st + k1 x V + k2 x V2 + PEEPtot Vassiliou MP, Petri L, Amgdalou A, et al. Linear and nonlinear analysis of pressure and flow during mechanical ventilation. Intensive Care Med 2000; 26: 1057-1064 静态静态PV曲线曲线: 多元线性回归模型多元线性回归模型 Mols G, Brandes I, Kessler V, et al. Volume-dependent compliance in

47、ARDS: proposal of a new diagnostic concept. Intensive Care Med 10999; 25: 1084-1091 静态静态PV曲线曲线: 多元线性回归模型多元线性回归模型 Lichtwarck-Aschoff M, Kessler V, Sjostrand UH, et al. Static versus dynamic respiratory mechanics for setting the ventilator. Br J Anaesth 2000; 85: 577-586 静态静态PV曲线曲线: 总结总结 临床可行的测定方法 吸气阻

48、断法和准静态法 操作要求和影响因素 临床意义有待确定 呼吸系统压力容积曲线呼吸系统压力容积曲线 反映肺和胸廓的静态机械力学特征 了解患者的病理生理学改变 设置机械通气参数 静态静态PV曲线的测定方法曲线的测定方法(I): 超大注射器法超大注射器法 Matamis D, Lemaire F, Harf A, et al: Total respiratory pressure volume curves in the adult respiratory distress syndrome. Chest 1984; 86: 58-66 静态静态PV曲线的测定方法曲线的测定方法(II): 吸气阻断法吸气阻断法 Barberis L, Man