新生兒呼吸窘迫綜合征

NeonatalRespiratoryDistressSyndrome

新生兒呼吸窘迫綜合征AlsoknownashyalinemembranediseaseOverviewHMD肺透明膜病OverviewMostcommondisorderinpreterminfantsSurvival>90%Sequelae:chroniclungdisease慢性肺疾病

ProgressivelyrespiratorydistressafterbirthOverviewIncidenceTerm <2%36weeks 5%32weeks 25%28weeks 70%26weeks 90%

Incidenceandseverityincrease

withdecreasinggestationageRDSProphylaxisEtiologyPathophysiologyClinicalPresentationsManagementDiagnosisEtiologyStructuallyimmaturelungDecreasednumberandsizeofalveoli肺泡WeakchestwallmusclesPulmonarysurfactant(PS)deficiency

肺表面活性物質(zhì)缺乏ConfirmedbyAvery&Meadin1959

EtiologyMaturelungImmaturelungWhatisPS?Acomplexmixtureofphospholipids磷脂andproteinsSynthesizedandsecretedbyalveolartypeⅡcells肺泡Ⅱ型細胞Begintoproducefrom20-24weeksgestationandincreaserapidlytill35weeksRolesofPSDecreasessurfacetension表面張力atair-liquidinterfaceKeepslungalveoliopenStablizefunctionalresidualcapacity(FRC，功能殘氣量)Maintainnormaloxygenation氧合andventilation通氣RolesofPSSurfacetension表面張力RolesofPSSurfactantspreadsoutoversurfaceofalveoluswithweakerbondingINFLATION吸氣InhalationSurfactantcompressedoversurfaceofalveoluswithstrongerbondingandreducesincreasingsurfacetensionEXPIRATIONExhalation呼氣(Laplace’slaw)PathophysiologyDiminishedsurfactantSupressedsurfactantsynthesis/activityImpairedcellularmetabolismDeterioratedbloodgasDefectedgasdiffusion氣體彌散障礙↑pCO2,↓pO2,↓pHVentilation-perfusionmismatching

通氣血流比例失調(diào)Generalizedatelectasis

廣泛性肺不張ProteinaceousdebrisleakageHyalinemembraneformation肺透明膜形成PrematuritySurfactantdeficiencyViciouscircleRiskFactorsPrematurity早產(chǎn)Infantsofdiabeticmothers糖尿病母親嬰兒Cesareandeliverywithoutlabor無宮縮剖腹產(chǎn)Perinatalasphyxia圍產(chǎn)期窒息Multiplebirth多胎妊娠Male男性ClinicalPresentationsTachypnea氣促Grunting呻吟Nasalflaring鼻搧Chestretraction

三凹征Cyanosis紫紺Decreasedbreathsoundsbilaterally

雙肺呼吸音減低Progressivelyrespiratorydistressoverthefirstfewhoursafterbirth生后數(shù)小時（6h）內(nèi)出現(xiàn)呼吸困難，并進行性加重ClinicalPresentationsChestX-rayDiffusereticulargranularpatterninbothlungfields彌漫性網(wǎng)狀顆粒影Groundglass

毛玻璃樣改變ClinicalPresentationsChestX-rayAirbronchograms

支氣管充氣征SmalllungVolumes肺容量減少Unclearcardiacborder心界模糊Whitelung白肺LaboratorytestsFoamtestNofoam---RDSAssessmentoffetallungmaturity胎肺成熟度判定Lecithin-sphingomyelin(L/S)ratio

卵磷脂/鞘磷脂比值

L/S≥2matureL/S1.5-2questionableL/S〈1.5immatureBloodGas血氣分析Acidosis/hypoxia/hypercarbiaComplicationsPatentductusarteriosus,PDA

動脈導管未閉Pulmonaryairleak肺氣漏

Pneumothorax氣胸BronchopulmonaryDysplasia支氣管肺發(fā)育不良

Chroniclungdisease慢性肺疾病Retinopathyofprematurity,ROP

早產(chǎn)兒視網(wǎng)膜病Ventilatorassociatedpneumonia

呼吸機相關(guān)性肺炎

ComplicationsPDA動脈導管未閉Lefttorightshunt左向右分流IncreasedFiO2，apnea呼吸暫停，metabolicacidosis，feedingdifficulty↑Pulsepressure脈壓差增大Boundingpulse水沖脈Murmur心臟雜音↑HeartrateCardiomegaly心臟擴大DifferentialDiagnosisGroupBstreptococcalpneumonia

B族β溶血性鏈球菌感染SimilarchestX-ray/Maternalinfection/pretermruptureofthemembrane胎膜早破Wetlung濕肺Term/transienttachypnea/CXR/improvein1-2dDiaphragmatichernia膈疝

ComplicationsCXRofDiaphragmatichernia

左側(cè)胸腔內(nèi)可見充氣的胃泡和腸管影，縱隔向?qū)?cè)移位DiagnosisCasestudyBabyC,boy,G2P2,GA32W,C-sectiondeliveryduetoantenatalbleedingBW1.8Kg,Bloodyamnioticfluid血性羊水,Apgarscore81,85Gruntingandretractingat10minutesafterbirthDiagnosisCasestudyCyanosiswasnoticed,oxygenwasgiven,transfertoNICUBloodgasat30minutesafterbirth:

PH7.20PCO265mmHgPO248mmHgBE-6mmol/LHCO3-18mmol/LMixedrespiratory&metablicacidosisDiagnosisChestX-rayImpression?Don’tforgettoruleoutinfection!DiagnosisHistoryPrematurityInfantofdiabeticmatherProgressiverespiratorydistressoverthefirstfewhoursafterbirthChestX-rayDiffusereticulargranularpatternGroundglassAirbronchogramsWhitelung

ManagementGeneraltreatment:KeepwarmFluid&nutritionCardiacsupportAntibioticsRespiratorysupportManagementRespiratorysupportOxygenNasalCPAP（ContinuousPositiveAirwayPressure持續(xù)氣道正壓通氣）Mechanicalventilation

機械通氣Surfactantreplacementtherapy

替代治療NaturalSyntheticalNasalCPAPPressure:4-6cmH2ONasalCPAPMechanicalVentilationIndications:PaO2<50mmHginFiO20.6PaCO2>60mmHgPH<7.25SurfactantReplacementTherapySurfactantReplacementTherapy100-200mg/kggiventhroughendotrachealtube氣管導管Mayrepeat1-2dosesevery6-12hoursaccordingtothepatientstatusGiveasearlyaspossible5s10s15s25s20s30s40s50sSurfactantinstillation:1min2min4min6min8min12min16min20min24min8minSurfactantinstillation:2-24min35

BeforePS

AfterPS

ChestX-ray

Meta-analysis:SurfactantTx

Deathorsevere

disability

at1-2yearsofage

SurfactantControlOR95%CI

1100/35211260/35130.80.7-0.9SinnJKH,etal.JPaediatrChildHealth2002;38:597TreatmentforPDAClosetheductIndomethacin消炎痛0.2mg/kgivq12h×3Ibuprof