GAS MAN 应用在吸入麻醉教学中的体会.ppt

罗艳上海交通大学医学院附属瑞金医院,GasMan应用在吸入麻醉教学中的体会,Exercises,Wash-inofasinglecompartment,Wash-inofasinglecompartmentproducesanexponentialcurve,Wash-inofasinglecompartment,=t0.63equalsthetimerequiredforthecurvetoreach1-e-1,or63%ofitsfinalvalueAttheendof1,2,3,4,5timeconstants,thecircuittensionequals63%,87%,95%and99%ofthedeliveredfromthevaporizer,Wash-inofasinglecompartment,=V/FThetimeconstantsforwash-inofasinglecompartmentequalseffectivevolumedividedbyeffectiveinflowrate,Wash-inofasinglecompartment,=V/FCircuitvolumeis8liters=V/F=8/4=2minInspiredtensionreached63%ofdelivered,TwoSequentialCompartments,BreathingcircuitpatientslungsLungs=FRC/VAFRC:functionalresidualcapacityVA:alveolarventilation,TwoSequentialCompartments,Lungs=FRC/VAFRC:functionalresidualcapacityVA:alveolarventilationAlveolartensioncurve(ALV)looksidenticaltotheinspiredtensioncurve(CKT),TwoSequentialCompartments,OverpressurecanspeedtheriseinanesthetictensiontowcompartmentsawayObjective:achieve70%alveolartensionsmoothlyandquickly,AlveolarTensionCurve,Opencircuitalveolartensioncurveisthealveolarresponsetoastepchangeininspiredtension,representingpatientwash-in,AlveolarTensionCurve,AlveolarTensionCurve,Initialriseinthealveolartensioncurveisresultsfromalveolarwash-inresponsivetoastepchangeininspiredtension,AlveolarTensionCurve,AlveolarTensionCurve,Lowerventilationslowsinitialriseinalveolartension,AlveolarTensionCurve,VA：7.5-1.25：0.33-2,AlveolartensionreachafinalvalueequaltoinspiredtensionundertheconditionofCO=0,AlveolarTensionCurve,UptakeproducesakneeandplateauinalveolartensionDisablereturn:emptyvenousanesthetictensionbar(VEN)3minpause,AlveolarTensionCurve,Increasingalveolarventilationraisesthekneeandplateau6minpause,AlveolarTensionCurve,Increasingcardiacoutputlowersthekneeandplateau9minpause,7.5,AlveolarTensionCurve,AlveolarTensionCurve,Kneeorplateauheightdeterminedbytheratioofalveolarventilationtocardiacoutput?,AlveolarTensionCurve,AtconstantCO,increasingVAinastepwisefashioncauseastepwiseriseinalveolarplateauheightSetbreakpointsateveryminuteupto10and15Ateachminute,increaseVAbyone,AlveolarTensionCurve,AtconstantVA,decreasingCOinastepwisefashioncauseastepwiseriseinalveolarplateauheightSetbreakpointsateveryminuteupto10and15Ateachminute,reduceCOby1L/minuntil0,AlveolarTensionCurve,10,5,AlveolarTensionCurve,Kneeandplateauheightisdeterminedbytheratioofalveolarventilationtoeffectivecardiacoutput,AlveolarTensionCurve,Anestheticreturnedtothelungsinvenousbloodconvertsthealveolartensioncurveplateauintoagently-risingtailSetabookmarkat2minutesDeselectdisablereturncontinue,AlveolarTensionCurve,AscendingtailproducedbytheadditionofanestheticreturninginvenousbloodVenousanesthetictensionisdeterminedbythearterialbloodanesthetictension,tissuebloodflowandtissuecapacity,BloodGasSolubility,