1、北京协和医院北京协和医院杜斌杜斌机械通气患者的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静态法(static method)准静态法准静态法(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曲线的测定方法静态PV曲线的测定方法(I):超大注射器法测定前的准备工作镇静+肌松测定前15分钟预氧合FiO2 1.0PEEP 0准备好
2、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PV曲线的测定方法(I):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.Che
3、st 1984;86:58-66静态PV曲线的测定方法(I):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,Lemaire F,Harf A,et al:Total respiratory pressure volume curves in the adult respiratory distress syndrome.
4、Chest 1984;86:58-66静态PV曲线的测定方法(I):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PV曲线的测定方法(I):超大注射器法Matamis D,Lemaire F,Harf A,et al:Total respiratory pressure volume curves in the adult respiratory dist
5、ress 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优点缺点缺点测定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PV曲线的测定方法(I):超大注射器法Lu Q,Rouby JJ.Measurement of pressure-volume curves in patients on mech
6、anical ventilation:methods and significance.Crit Care 2000;4:91-100静态PV曲线的测定方法(II):吸气阻断法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PV曲
7、线的测定方法(II):吸气阻断法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PV曲线的测定方法(II):吸气阻断法Levy P,Simil
8、owski 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
9、力并作图静态PV曲线的测定方法(II):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PV曲线的测定方法(II):吸气阻断法Barberis L,Manno E,Guerin C.Effect of end-inspiratory pause duration on plateau pressure in mec
10、hanically ventilated patients.Intensive Care Med 2003;29:130-134静态PV曲线的测定方法(II):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;29:130-134Volume history对PV曲线测定的影响Takeuchi M,Sedeek KA,Schettino G
11、PP,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PV曲线测定的影响Nishida T,Suchodolski K,Schettino GPP,et al.Peak volume history and peak pressure-volume curve pressures independently affect the s
12、hape of the pressure-volume curve of the respiratory system.Crit Care Med 2004;32:1358-1364Volume history对PV曲线测定的影响Nishida T,Suchodolski K,Schettino GPP,et al.Peak volume history and peak pressure-volume curve pressures independently affect the shape of the pressure-volume curve of the respiratory s
13、ystem.Crit Care Med 2004;32:1358-1364Volume history对PV曲线测定的影响Nishida T,Suchodolski K,Schettino GPP,et 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优点优点缺点缺点患者无需脱离呼吸机
14、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PV曲线的测定方法(II):吸气阻断法Lu Q,Rouby JJ.Measurement of pressure-volume curves in patients on mechanical ventilation:methods and significance.Crit Care 2000;4:91-100准静态PV曲线的测定方法(I):低流量法测定原理:顺应性计算公式Compliance=DvolumeDpresssureCom
15、pliance=Dvolume/timeDpresssure/time准静态PV曲线的测定方法(I):低流量法测定原理:顺应性计算公式Compliance=VDpresssure/time若V(t)恒定则克服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PV曲线的测定方法(I):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/secPV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P
16、EEP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(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PV曲线的测定方法(I):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 1980,49:1116-1121Sura
17、tt PM,Owens DH:A pulse method of measuring respiratory system compliance in ventilated patients.Chest 1981,80:34-38Ranieri 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 Res
18、pir Crit Care Med 1994,149:19-27Servillo 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 1997,155:1629-1636Lu Q,Vieira S,Richecoeur J,et al:A simple automated method for measuring pressure-volume
19、 curve during mechanical ventilation.Am J Respir Crit Care Med 1999,159:275-282准静态PV曲线的测定方法(I):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 sServillo 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LIPMankikian B,Lemaire F,Beni
20、to S,et al:A new device for measurement of pulmonary pressure-volume curves in patients on mechanical ventilation.Crit Care Med 1983；11:897-901Servillo G,Svantesson C,Beydon L,et al:Pressurevolume curves in acute respiratory failure.Automated low flow inflation versus occlusion.Am J Respir Crit Care
21、 Med 1997,155:1629-163准静态PV曲线的测定方法(I):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与吸气阻断法相比与吸气阻断法相比呼吸系呼吸系统顺应统顺应性性,UIP和和LIP均相同均相同Paw=Pressure+PelPressure=Flow x Raw当吸气流量0Pressure 0Paw 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
22、in acute respiratory failure.Automated low flow inflation versus occlusion.Am J Respir Crit Care Med 1997,155:1629-1636Lu 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PV曲线的测定方法(I
23、):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PV曲线的测定方法(I):低流量法Krason S,Sndergaard S,Lundin S,Wiklund J,Stenqvist O.Evaluation of pressure/volume loops based on intratracheal pressure measurements dur
24、ing dynamic conditions.Acta Anaesthesiol Scand 2000;44:571-577准静态PV曲线的测定方法(I):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与吸气阻断法相比与吸气阻断法相比呼吸系呼吸系统顺应统顺应性性,UIP和和LIP均相同均相同Paw=Pressure+PelPressure=Flow x Raw当吸气流量0Pressure 0Paw Pel如何提高准静态PV曲线的准确性Servillo G,Svantesson
25、 C,Beydon L,et al:Pressurevolume curves in acute respiratory failure.Automated low flow inflation versus occlusion.Am J Respir Crit Care Med 1997,155:1629-1636Lu Q,Vieira S,Richecoeur J,et al:A simple automated method for measuring pressure-volume curve during mechanical ventilation.Am J Respir Crit
26、 Care Med 1999,159:275-282准静态PV曲线的测定方法(I):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 1999,159:275-282呼吸机设置容量控制通气模式吸气流量恒定呼吸频率 5 lpmI:E4:1VtFlow设置1500 mL3 lpm设置21500 mL9 lpm准静态PV曲线的测定方法(I):低
27、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 1999,159:275-282准静态PV曲线的测定方法(I):低流量法Lu Q,Vieira S,Richecoeur J,et al:A simple automated method for measuring pressure-volume curve during mechanic
28、al ventilation.Am J Respir Crit Care Med 1999,159:275-282PEEPi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PV曲线的测定方法(I):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
29、Respir Crit Care Med 1999,159:275-282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优点缺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PV曲线的测定方法(I):低流量法Lu Q,Rouby JJ.Measurement of pressure-volume curves in patients on mechanical venti
30、lation:methods and significance.Crit Care 2000;4:91-100Draeger 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PV曲线的测定方法(II):改良低流量法准静态PV曲线的测定方法(II):改良低流量法www.intelligentventilation.org/./PN%20689213_PV-Tool_WP_01-Validation_of_New_Method.pdfPiacentini E,Wysocki M,Blanch L.
31、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;35:565-570Hamilton Galileo Gold采用的改良低流量法测定吸气与呼气PV曲线与CPAP方法相同与低流量法相同低流量: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
32、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 infection point in acute respiratory distress syndrome patients.Artif Organs 2001;25:882-889低流量:How Low i
33、s 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 to the resistance of flow through airways and tracheal cannula(P1=Pmax Pi)increases with higher flows,whereas the
34、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 curves is to use a flow that makes P1 negligible.Paw=airway pressure,Pmax=maximum airway pressure,Pi=pressure at the beginning of
35、 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 setting when measuring the pressure-volume relationship.Anesth Analg 2003;97:145-150低流量:How Low is Low?Bensenor FE,Vieira JE,Auler JOC.Guideli
36、nes for inspiratory flow setting when measuring the pressure-volume relationship.Anesth Analg 2003;97:145-150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:How Low is Low?Bense
37、nor FE,Vieira JE,Auler JOC.Guidelines for inspiratory flow setting when measuring the pressure-volume relationship.Anesth Analg 2003;97:145-150呼吸系统静态PV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
38、 and the inner Ptrach/V-loop mainly represents the flow-dependent resistive pressure drop across the ETT.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.
39、slices 1 and 8,respectively)are excluded from analysis.The remaining 90%of VT are divided into 6 slices.One volume-dependent dynamic compliance and resistance of the respiratory system(Crs,dyn and Rrs,dyn)are calculated per slice.(C)Quality check:Ptrach is recalculated point by point for each slice,
40、using the calculated values for Crs,dyn and Rrs,dyn and the measured volume and 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 recalculate
41、d loops in C are barely distinguishable.Paw-Volume CurveLichtwarck-Aschoff 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PV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
42、线性回归模型(multiple nonlinear regression model)Paw=Vt/Crs,st+k1 x V+k2 x V2+PEEPtotVassiliou 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PV曲线:多元线性回归模型Mols G,Brandes I,Kessler V,et al.Volume-dependent c
43、ompliance in ARDS:proposal of a new diagnostic concept.Intensive Care Med 10999;25:1084-1091静态PV曲线: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PV曲线:总结临床可行的测定方法吸气阻断法和准静态法操作要求和影响因素临床意义有待确定
