新生儿黄疸 .ppt

NeonatalJaundice,(Hyperbilirubinemia),Introduction,Allbabiesdevelopelevatedserumbilirubin(SBR)levels,toagreaterorlesserdegree,inthefirstweekoflife.Thisisdueto:increasedproduction(acceleratedRBCbreakdown);decreasedremoval(liverenzymeinsufficiency)Increasedreabsorption(enterohepaticcirculation).,Introduction,60%ofinfantsbecomeclinicallyjaundicedin1stwkBililevelspeakat35daysinfullterminfants1/6offormulafedinfantshavebililevelsover121/3ofbreastfedinfantshavebililevelsover12Over80%ofallinfantswithbililevels12.9mg/dlinthefirstfourdaysoflifearebreastfed,BilirubinMetabolism,derivedfromthecatabolismofproteinsthatcontainhemethemostimportantsourceisthebreakdownofHbfromRBCnativebilirubinisrelativelyinsolubleinwateratphysiologicpH,butitisverylipidsolublebilirubincirculatesboundtoalbumininequilibriumwithitsunboundorfreefractiontheunboundfractionthatreadilycrossestheblood-brainbarrierandresultsinneurotoxicity,BilirubinMetabolism,Bilirubinismademorewater-solubleintheliverbyconjugationwithglucuronicacidtoformconjugatedordirect-reactingbilirubin,thenclearedthroughthebileintotheintestinesandoutthroughthefeces.Phototherapyworksbyproducingphotoisomersofbilirubinthataremorewatersoluble,andthatcanbecleareddirectlyinbileorurinewithoutconjugationintheliver.“enterohepaticcirculation”:b-glucuronidaseintheguthydrolysistheconjugatedbilirubinintounconjugatedbilirubin,andreabsorbedintoliver,CharacteristicsofNeonatalBilirubinMetabolism,Increasedbilirubinproduction8.8mg/kgdailyvs3.8mg/kginadultsInsufficiencyofbilirubintransportationacidosis,hypoalbuminemiaImmatureofliverfunctionloweringestion(y,zprotein);lowerUDPGTactivityIncreased“enterohepaticcirculation”loweringutbacteria;higherb-glucuronidaseactivity,“Physiological”Jaundice,Seenin60%ofterminfantsandover80%ofpretermSerumvaluesreachesmaximumat6mg/dlon45dintermand1012mg/dlon57dinprematureinfantsJaundicedeclinesgradually,reachingnormalvalueswithin2wksinterm,and34w(12m)inpretermCausesnodamageinterminfantsUplimitforabnormal?Undefined(Term12mg/dl,orterm5mg/dl/daySustainedjaundice(term2w,preterm4w)RecurrenceofjaundiceIncreasedserumconjugatedbilirubin(1.52mg/dl),PathologicalJaundice,InfectiousdiseasesNeonatalhepatitis(Torchinfection)NeonatalsepticemiaNon-infectiousdiseasesHemolyticdiseasesBiliaryatresiaBreastmilkjaundiceGeneticmetabolicdiseases:G6PD,a1-antitrypsin,CFDrugsinduced:VitaminK3,K4,BreastMilkJaundice,Occursinfrequently(1%),peaksin23wk,maypersistatmoderatelyhighlevelsfor3-4weeksbeforedecliningslowlyItisadiagnosisofexclusionInanotherwisewellinfant,itisconsideredabenigncondition.Ifbreastfeedingstopped,theserumbilirubinusuallyfallsThepotentialharmsofstoppingbreastfeedingwouldoutweighanyrisksofamildormoderatehyperbilirubinaemiaAetiologyisunknown,somehormonalinthemilkmayactingontheinfantshepaticmetabolism,orenzyme(lipase)facilitatingintestinalabsorptionofbilirubin.,Breast-feedingJaundice,increasedbilirubinlevelsseenduringthefirstweekoflifeininfantswhoarebreastfedduetobothcaloricdeprivation(mostly)andsomefluiddeprivation(asmallpart)duringthefirstfewdaysoflifeThemorefrequentlybreastfeedingoccursduringthefirstfewdays,theloweraresubsequentbililevelscanbepreventedbyteachingeffectivebreast-feedingpracticesandsupportpolicies,ClinicalInvestigation:KramersRule,CephalocaudalProgressionofJaundice,ClinicalInvestigation,TotalSBRconjugatedSBRfullbloodcount-mayrevealspherocytesorsepticGroupdisordersineyemovement;enamelhypoplasia,Diagnosis,Familyhistory:stillbirth,abortion,jaundiceParentsABO/Rhtyping,antibodyUltrasoundforhydropsfetalisPostnatal:jaundice,anemia,neurologicalsymptomBloodtypeandantibody,DirectCoombs,Antibodyrelease,ortypeOVolume:150180ml/kgviaumbilicalveincatheter,OtherIntervention,Albumin(1g/kg),plasma(25ml)CorrectacidosisPhenobarbitone(5mg/