Respiratory-Failure-呼吸衰竭VIP免费

RespiratoryFailure第一页，共四十九页。1.AbstractsRespiratoryfailure,whetheracuteorchronic,isafrequentlyfacedproblemandamajorcauseofdeathinourcountry.Forexample,mortalityfromCOPD,whichendsindeathfromrespiratoryfailure,continuestoincrease.Morethan70%ofthedeathsinpatientswithpneumoniaareattributedtorespiratoryfailure.第二页，共四十九页。2.DefinitionRespiratoryfailureisfunctionalacuteorchronicdisordercausedbyanyconditionthataffectsthelung’sabilitytomaintainarterialoxygenationorcarbondioxide(CO2)elimination.Itisdefinedasaconditioninwhichthisgasexchangedeterioratesbelowtheusuallevel,sothatarterialoxygentensiondecreases,withorwithoutanabnormalriseinarterialcarbondioxidetension.第三页，共四十九页。3.ClassificationsGenerallybothacuteandchronicrespiratoryfailuremaybedividedintotwomaincategories:第四页，共四十九页。TyperespiratoryfailureⅠTyperespiratoryfailureisalsocalledⅠhypoxicrespiratoryfailure,whichmeansthatseverelyreducesarterialoxygentension(PaO2<60mmHg),CO2retentionisnotexist.Thistypeofrespiratoryfailureiscausedbyafailureofgasexchange.第五页，共四十九页。TyperespiratoryfailureⅡTyperespiratoryfailureisalsomeantthatⅡhypercapnic-hypoxicrespiratoryfailure.Arterialbloodgasvaluesshowsthatarterialcarbondioxidetensionismorethan50mmHgandarterialoxygentensionislessthan60mmHgTyperespiratoryismainlycausedbyⅡhypoventilation.第六页，共四十九页。PathogenesisMainlydiscusschronicrespiratoryfailurewehaveknownthatthelungs’abilityisgasexchange.Thegasexchangeinvolvesnotonlyoxygenationbutalsocarbondioxideelimination.第七页，共四十九页。PathogenesisRespiratoryfailureismainlyassociatedwithpulmonarygasexchangeandpulmonaryventilation.第八页，共四十九页。1.pulmonarygasexchangeismainlydeterminedbyventilation-perfusion(V/Q)ratiosanddiffuseabilityV/Qmismatch:AneffectivelunggasexchangeneedsnotonlysufficientlungventilationandlungbloodvolumesbutalsoanadequateV/Qratios.Usually,thevolumeofventilationis4liters/min.Thevolumeoflungbloodis5liters/min.Sotheratiosis0.8第九页，共四十九页。Anyofthefactorsinfluencedtheratiosmaymainlycausehypoxemiarespiratoryfailure.Forexample,V/Q>0.8,includingemphysema,pulmonaryembolism.V/Q<0.8,includingatelectasis,severeCOPD.第十页，共四十九页。DiffuseabilityDiffusionabnormalitymainlyinfluenceoxygenexchange.第十一页，共四十九页。2.PulmonaryhypoventilationItmaycausehypercapnic-hypoxicrespiratoryfailure.Pulmonaryhypoventilationincludesrestrictivehypoventilationandobstructivehypoventilation.Somediseasesinfluencedcentralnervoussystem,peripheralnervoussystem,chestwallrespiratorymusclesandpulmonarycompliancemayallcauserestrictivehypoventilation.第十二页，共四十九页。SomecommonconditionsthatmaycauseventilatoryfailurewithhypercapneaTheseconditionsincludebrainstemlesion,alteredneuromusculartransmission(guillain-barresyndrome),muscleweakness(malnutrition,shock,hypoxemia,hypokalemia),increasedairwayresistance(upperairwayobstruction,increasedbronchialsecretionsandedema),decreasedlungcompliance(infection,atelectasis,interstitialfibrosis,acutelunginjury),decreasedchestwallcompliance(chestwalltrauma,pleuraleffusion,pneumothorax).第十三页，共四十九页。COPDandasthmaarethemostcommondiseaseassociatedtoobstructivehypoventilation.Inourclinicalwork,multifactorsinvolveinthecourseofrespiratoryfailure.Forexample,aCOPDpatientwithseverepulmonaryinfection,hisp...