stressindex病理生理基础VIP免费

StressindexStressindex病理生理基础病理生理基础VentilationinALIBackgroundALI是ICU常见的危重病病理生理特点肺容积明显降低肺顺应性明显下降通气/血流比例失调肺组织分布“不均一”TIDALrecruitmentend-expirationend-inspirationTIDALhyperinflationend-expirationend-inspirationbackgroundIntensiveCareMed,2005,31:776–784非重力依赖区过度膨胀重力依赖区潮汐性塌陷复张BestPractice&ResearchClinicalAnaesthesiology2010;24:171-182.VILI立项依据Alwaysopeningandclosing－－VILI●●●●●●●●●●●●●●●●●●●TidalcollapseVT01020304001020304050%Paw(cmH2O)●Closingpressure●OpeningpressureCrotti,etalAmJRespirCritCareMed2001;164:131-140●●●●●●●●●HEARTSPPEEP--KeepthelungopenLowVtRMOpenlungBackgroundARDS病理生理变化－－肺保护性通气机械通气患者病死率仍高达37%IntensiveCareMed2009;35:816–825.13,322patsadmittedto299ICUsfrom35countriesBackground6ml／Kg－－小潮气量非重力依赖区肺泡依然过度膨胀Background中大医院重症医学科－－预试验重力依赖区通气不良和塌陷肺泡明显增加Background中大医院重症医学科－－预试验HEARTSPAtpresent：LungProtectiveVentilationStrategies非重力依赖区肺泡过度膨胀重力依赖区肺泡潮汐性塌陷复张BackgroundVILI几乎无处不在潮气量和PEEP的设定依然矛盾重重潮气量设置困难－－个体化难！•重症ARDS－－大量肺泡塌陷•即使“小”潮气量仍然导致VILI•潮气量应更小•VILI－－塌陷肺泡少•“小”潮气量太小，肺泡通气无法保证，导致肺泡塌陷•显然，6ml／Kg的“小”潮气量不适合所有ARDSThemostcontroversialissueinALI/ARDSpts维持肺开放维持肺开放(KeepLungOpen)(KeepLungOpen)--------最佳最佳PEEPPEEPPEEP水平不足肺泡反复塌陷、复张，产生剪切力VILIPEEP水平过高肺泡过度膨胀，导致气压伤VILI立项依据立项依据MethodstotitratePEEPinALI/ARDS•BestPEEP(Suter,NEJM,1975)•SuperPEEP(Kirby,Chest,1975)•Pflex(Amato,AmJRespirCritCareMed,1995)•Oxygenationscale(ARDSnet,NEJM,2000)•Stressindex(Ranieri,Anesthesiology,2000)•Pmc(Goddon,Anesthesiology,2001)•FRC+Cst(Lambermont,CriticalCare,2008)•Pes(Talmor,NEJM,2008)•Increasedrecruitmentstrategy(Mercat,JAMA,2008)•EIT(Meier,ICM,2008)•…Whichoneisbest?滴定PEEP的最佳方法•简便、床边•快速•安全•可重复，为PEEP滴定提供可靠信息Stressindex---肺牵张指数容量控制通气、恒定流速Stressindex---肺牵张指数P-t曲线吸气支：曲线回归方程P=a*tb+cb值：肺牵张指数描述曲线的形状，反映肺泡开放与塌陷程度的力学指标SlutskyAS,Aneathiology,2000,93:1320-8GrassoS,CritCareMed,2004,32:1018–27RanieriVMetalAnesthesiology2000Stressindex---肺牵张指数stressindex=1beforeRMstressindex=1afterRM0.61(1.1