新生兒呼吸窘迫綜合癥(Neonatal-Respiratory-Distress-Syndrome)課件

NeonatalRespiratoryDistressSyndrome(NRDS)NeonatalRespiratoryDistress1Hyalinemembranedisease(HMD)

MostcommoncauseofrespiratoryfailureinthefirstdaysintheprematureinfantsReasonissurfactantinsufficientinlungswhichleadtobreathingfailureandneedtheassistantventilationOccurringin1~2%ofnewborninfants,increasesbysmallerGA:50%ofGA<28w,lessthan30%of32~36w)Hyalinemembranedisease(HMD)2SurfactantKeepthelungalveoliopenStartsynthesisinGA24~28wbylungtypeIIalveolarcellsIncreasein28~35w,butproduceadequateamountsafter35wdoubleinalveolarwithin24hafterbirth,toadultlevelafter3~7dofbirthhalf-life12~24hSurfactantKeepthelungalveol3SurfactantCompositionPhospholipid(PL)90%(neutral5%) Phosphatidylcholin(PC,Lecithin)40％ Phosphatidylglycerol(PG)5％Sphingonyeline(S)2%othersProtein 10％ A,30~35kDa,18oligomer,D,43kDa,12oligomer B,8kDa,dimer,C,4kDa,dimerSurfactantCompositionPhosphol4FunctionofPulmonarySurfactantloweralveolarsurfacetension,reducesrespiratoryworkMaintainalveoliinflationandfunctionalresidualcapacityAcceleratelungfluidabsorption,reducealveolareffusionPathogenOpsonization,alveolarmacrophageactivation

Effects:increaseoxygenation,ameliorateventilation/perfusionanti-inflammationFunctionofPulmonarySurfacta5Etiology

Riskfactors:

CaucasianormalebabiesPreviousbirthofbabywithRDSCesareandelivery(morewaterinlung)PerinatalasphyxiaMultiplebirths(multiplebirthbabiesareoftenpremature)Infantsofdiabeticmothers(toomuchinsulininababy'ssystemmaydelaysurfactantproduction)PerinatalinfectionBabieswithpatentductusarteriosus(PDA)

EtiologyRiskfactors:6PathophysiologyLackofsurfactantinthelungsofinfants

AveryandMead,AmJDisChild1959

progressiveatelectasislossoffunctionalresidualcapacity(FRC)alterationofventilation-perfusionratioWeakrespiratorymusclesandcompliancyofchestwallimpairalveolarventilationDiminishedoxygenation,cyanosisandacidosisincreasedpulmonaryvascularresistance(PVR)right-to-leftshuntingthroughductusarteriovenousintrapulmanaryventilation-perfusionmismatchPathophysiology7EtiologyandPathophysiology

Pulmonaryimmaturityresultsinsurfactantdeficiency

Alveolicollapseattheendofexpirationleadstorespiratoryfailure

Surfactantdeficiencymayariseafterasphyxia/shockandacidosisalveolarsurfacetensionishigherDiminishedPSPulmonaryatelectasisImpairedgasexchange(hypoxiaandacidosis)PulmonaryarteryhypertensionRight–to-leftheartshuntPulmonarycapillarypermeabilityincreaseFormingpulmonaryhyalinemembraneEtiologyandPathophysiologyal8Pathologyatelectasis,pulmonaryedema,vascularcongestion,hemorrhage,generalizedcapillaryleakandmucosalnecrosisleadstothesmallerairfilledterminalairways;therespiratorybronchiolesandalveolarductsaresurroundedbycollapsedalveolifilledwithdebrisinanearuniformdistribution(hyalinemembranes)Pathologyatelectasis,pulmonar9ClinicalPresentationPresentatbirthorfirst2to6hofbirth:respiratorydifficultythatgetsprogressivelyworsetachypnea(rapidbreathing)cyanosis(bluecoloring)withincreasingoxygenrequirementschestretractionsnasalflaringgruntingsoundswithbreathingCharacterizedbyprogressiveworseningofcyanosisanddyspneasymptomsusuallypeakon2to3day,andwillrecoveryafter3dClinicalPresentationPresenta10DiagnosisDiagnosiscanbedecidedbyacombinationofassessments,includingGA,ahistoryofriskfactors,thesigns,chestX-rayandbloodgases.DiagnosisDiagnosiscanbedeci11RadiographicChangesofRDS

abellshapedthoraxwithdiffuseandsymmetrical“groundglass”calledreticulogranularpatternwith“airbronchogram”,orseverebilateralopacityandobliteratethecardiacborder,

“white-outlung”

RadiographicChangesofRDSa12LaboratoryFindingsMixedacidosisLecithin(L)/Sphingomyelin(S)<2:1;orPhosphatidylglycerol(PG)negativeFoamTest:Inatube

+95%ethanol,1ml

+amnioticfluid(gastricjuice),1ml

shake:15”,staticstates:15”,evaluation:bubblepresentLaboratoryFindingsMixedacido13DifferentialDiagnosis

allthecausesofrespiratorydistress

“Wetlung”ortransientrespiratorydistress

AmnioticfluidormeconiumaspirationsyndromeGroupBhemolyticStreptococcuspneumonia

DiaphragmaticherniaPneumothoraxDifferentialDiagnosisa14DifferentialDiagnosis–MeconiumAspirationnodularnonhomogeneousdensities(bilateral,irregularcoarseinfiltrates),mayhavepleuraleffusions,usuallyhasanincreasedlungvolume.DifferentialDiagnosis–nodula15DifferentialDiagnosis--Wetlung

mildcardiomegalyandbilateralreticulonodulardensitiesthatradiatefromthehila;atelectasisintheupperlobesintervalclearanceofthereticulonodulardensitiesinthesamepatient1daylater.DifferentialDiagnosis--Wetl16TreatmentSupportivetreatment:MaintainaneutralthermaltemperatureAdministeradequatefluidsandelectrolytes,preventfluidoverload

Correctacid-basedisturbances

Specifictherapy

Surfactantreplacementtherapy(natural/synthetic)--Endotrachealintubation,Dose:50to200mg/kgContinuouspositiveairwaypressure(CPAP)Closureofthepatentductusarteriosus（PDA）

--indomethacintherapyAntibioticTreatmentSupportivetreatment:17RespiratoryManagementContinuousPositiveAirwayPressure(CPAP)

Indication:whenFiO2>0.6,PaO2<50mmHgorTcSO2<85%

Pressure:4~10cmH2O,flow5L/min,32°C,humidity100%ConventionalMechanicalVentilation(CMV)

Indication:PaO2<50mmHgorTcSO2<85%withCPAP(8cm);PCO2>70mmHg;orfrequentapnea

Complication:PAL(pulmonaryairleak)BPD(bronchopulmonarydysplasia;orCLD)Retinopathyofprematurity(ROP)VAP(ventilator-associatedpneumonia)RespiratoryManagementContinuo18ApplicationofPulmonarySurfactantIntratrachealinstillation:50~200mg/kg,6~12hintervalNeonatalRespiratoryDistressSyndrome(NRDS)meconiumaspirationsyndrome(MAS)PneumonicRespiratoryfailureAcutelunginjury,ARDSRespiratoryfailureafteropen-chestsurgeryorlungtransplantationApplicationofPulmonarySurfa19PreventionAvoidanceofpretermbirth:

mostimportant