呼吸衰竭和急性呼吸窘迫综合征-英文课件.ppt

UTHSCSAPediatricResidentCurriculumforthePICU RESPIRATORYFAILURE ARDS RESPIRATORYFAILURE Inabilityofthepulmonarysystemtomeetthemetabolicdemandsofthebodythroughadequategasexchange Twotypesofrespiratoryfailure HypoxemicHypercarbicEachcanbefurtherdividedintoacuteandchronic Bothtypesofrespiratoryfailurecanbepresentinthesamepatient CENTRALETIOLOGIES Trauma headinjury asphyxiation hemorrhageInfection meningitis encephalitisTumorsDrugs narcotics sedativesNeonatalapneaSeverehypoxemiaorhypercarbiaIncreasedICPfromanyoftheabovecauses OBSTRUCTIVEETIOLOGIES UpperAirwayAnatomic choanalatresia tracheomalacia tonsillarhypertrophy laryngealweb vascularrings vocalcordparalysis macroglossiaAspiration mucus foreignbody vomitusInfection epiglottitis abscesses laryngotracheitisTumors hemangioma cystichygroma papilloma Laryngpospasm LowerAirwayAnatomic bronchomalacia lobaremphysemaAspiration FB mucus meconium vomitusInfection pneumonia pertussis bronchiolitis CFTumors teratoma bronchogeniccystBronchospasm RESTRICTIVEETIOLOGIES LungParenchymaAnatomic agenesis cyst pulmonarysequestrationAtelectasisHyalinemembranediseaseARDSInfection pneumonia bronchiectasis pleuraleffusion PneumocystiscariniiAirleak pneumothoraxMisc hemorrhage edema pneumonitis fibrosis ChestWallMuscular diaphragmatichernia myastheniagravis musculardystrophy botulismSkeletal hemivertebrae absentribs fusedribs scoliosisMisc distendedabdomen flailchest obesity HYPOXEMIA V QmismatchMostcommonreason Bloodperfusesnon ventilatedlung Seeninatelectasis pneumonia bronchiectasisGlobalhypoventilation apneaRight to leftshuntIntracardiaclesions e g tetralogyofFallotIncompletediffusionOxygenmustdiffuseacrossincreaseddistancesecondarytointerstitialedema fibrosis orhyalinemembrane LowinspiredFiO2 highaltitude HYPERCARBIA PumpFailureReducedcentraldrive apnea metabolicalkalosis drugs brainsteminjury hypoxiaMusclefatigue musculardystrophyIncreasedpulmonaryworkload decreasedcompliance increasedobstructionIncreasedCO2production fever seizure malignanthyperthermiaIncreaseddeadspace V Qmismatch ventilationofnon perfusedlung PHYSICALEXAM TachypneaDyspneaRetractionsNasalflaringGruntingDiaphoresisTachycardiaHypertension AlteredmentalstatusConfusionAgitationRestlessnessSomnolenceCyanosis need5mg dlofunoxygenatedblood CXRFINDINGS CXRmaybenormalifproblemiswithupperairwayCanseehyperinflation atelectasis infiltrate cardiomegalyAdditionalstudiesmaybeneeded e g chestCT bariumswallow echocardiogram BLOODGAS Foranyagepatient breathingroomair respiratoryfailureisdefinedasarterialpCO2 50mmHgorarterialpO2 60mmHg Ifthepatientishyperventilating anormalpCO2isdisturbing Theabovedefinitionassumestheabsenceofananatomicshunt ChronichypercarbicrespiratoryfailurewilloftenhaveanormalpHbecauseofcompensatorymetabolicalkalosis MANAGEMENT REMEMBERPALSAirwayBreathingCirculation AIRWAY RepositioningPositionofcomfortJawthrust chinliftOralairwayUnconsciouspatientsonlyNasaltrumpetNasalormaskCPAPBag maskventilationUseduringpreparationforintubationTrachealintubation BREATHING Decreaserespiratoryworkload agonistsDecadronorsteroidsAntibioticsCPAPSupplementalO2NasalcannulaClosedfacemaskNon rebreatherCounteractdrugeffectsBag maskventilationMechanicalventilation CIRCULATION SuppressanaerobicmetabolismandacidosisCorrectanemiatoimproveoxygendeliveryEnsureadequatecardiacoutputInotropes oxygen vasopressorsFluidboluses ARDS Apatientmustmeetallofthefollowing AcuteonsetofrespiratorysymptomsCXRwithbilateralinfiltratesNoevidenceofleftheartfailurePaO2 FiO2 200mmHg regardlessofPEEP American EuropeanConsensusConferenceonARDS AmJRespCritCareMed149 818 1994 Thefollowingareimplied PreviouslynormallungsDecreasedlungcomplianceIncreasedshuntingHypoxemicrespiratoryfailure ETIOLOGY ARDSrepresentsabout3 ofPICUadmissions Numerousprecipitatingevents TraumaPneumoniaBurnsSepsisDrowningShock PATHOPHYSIOLOGY AcuteInjuryLatentPeriodEarlyExudativePhaseCellularProliferativePhaseFibroticProliferativePhase RoyallandLevinJPeds112 169 180 335 347 1988 PATHOLOGYOFARDS GreenarrowspointtohyalinemembraneBluearrowspointtotypeIIpneumocytesandalveolarmacrophages MANAGEMENT MeticuloussupportivecareisthemainstayoftherapyPreventsecondarylunginjuryEnsureadequatecardiacoutputLimitsecondaryinfectionsDrugsGoodnutrition VENTILATORSTRATEGIESThehallmarkofARDSisheterogeneouslung LimitBarotraumaKeepPIP7 20 LimitO2ToxicityGiveenoughPEEPtolowerFiO2to90 PEEPE ventilation CARDIACOUTPUT Keepcardiacoutput 4 5L min m2 KeepO2delivery 600mlO2 min m2 KeepHct 30 higherifsignsofheartfailure Useinotropestoaugmentcardiacoutput Ensureadequatepreload LIMITSECONDARYINFECTIONS Washyourhands Usethegutassoonaspossiblefornutritionandmeds Discontinueindwellingcathetersassoonaspossible Havehighindexofsuspicion Treatinfectionsearly buttailorantibioticstocultureresults DRUGS Diuretics adrylungisagoodlung InotropesSteroids 2mg kg daybegunafteraweekintothecoursemaybeofbenefit otherwisedon tuse Pulmonaryvasodilators nitricoxide prostaglandins nitroprusside oflittlebenefit NOmaybeofbenefitinsomepatients Surfactantreplacement probablynobenefitNSAIDs noclinicalbenefit NUTRITION Ensureadequatecaloriesassoonaspossible 50 60kcal kg dayininfants35 45kcal kg dayinolderchildren Afterday4 increasecaloriesby25 50 abovebaseline Beginenteralfeedsassoonasissafe Pulmonary formulasprobablyoflittlebenefit MORTALITY MORBIDITY Publishedmortalityis50 inchildren Pulmonaryfailureaccountsforonly15 ofthedeaths Lungfunctionusuallyreturnstonormalwithin18monthsafterleavingthehospital