腎功能檢驗(yàn)的學(xué)習(xí)課件

腎功能檢驗(yàn)的學(xué)習(xí)課件第1頁(yè)/共34頁(yè)FunctionsofthekidneyExcretionof

MetaboliteWaste:urea,uricacid,creatinineUrineProduction,regulationofhomeostasis,water,acidbasebalanceEndocrineFunction:renin,erythropoietin,

1,25-dihydroxycholecalciferol第2頁(yè)/共34頁(yè)RenalfunctiontestsDetectrenaldamageMonitorfunctionaldamageDistinguishbetweenimpairmentandfailure第3頁(yè)/共34頁(yè)KidneyFunctionAplumbersview第4頁(yè)/共34頁(yè)Howdoyouknowit’sbroken?NOUrine!ClinicalsymptomsTests第5頁(yè)/共34頁(yè)Wherecanitbreak?Pre-renalRenalPost-renal第6頁(yè)/共34頁(yè)LaboratorytestsofrenalfunctionGlomerularFunctionTestsRenalTubularFunctionTests第7頁(yè)/共34頁(yè)Section1InvestigationofGlomerularFunctionRenalBloodFlow:1200-1400ml/minRenalPlasma:600-800ml/min20%ofplasma:glomerularfiltrationGFR:GlomerularFiltrtionRateConcept

第8頁(yè)/共34頁(yè)RenalCleranceConceptVirtualvolumeofplasmafromwhichthesubstanceinquestionhasbeencompletelyremovedduringagiventimeinterval.C=UV/PU:urineconcentrtionP:plasmacon.

V:urineflowrate第9頁(yè)/共34頁(yè)UsefulnessofRenalCleranceFreelyfiltrated,neithersecreted,norreabsorbed:Inulin:GFRDeterminationFreelyFiltrated,smallamountssecreted,withoutreabsorption:Cretinine:GFRFreefiltrated,completelyreabsorption:GlucoseTubularMaximaReabsorptionRate第10頁(yè)/共34頁(yè)InulinClerancePolymeroffructoseMW:5500Freefiltration,withoutsecretionandreabsorptionGFRMethodReferenceInterval:2.0-2.3ml/min第11頁(yè)/共34頁(yè)EndogenousCreatinineClearance

100g,98%storedinmusle,MW:113Cretinephosphate---cretine—cretinineFreelyfiltration,smallmounts:secretionExogenousandEndogenousCreatinineGrosslyInvestigatetheGFR第12頁(yè)/共34頁(yè)Method24hurinecollectionmethodmodified4hurinecollectionmethodCleranceCorrection：CcrxSBSA/IBSA第13頁(yè)/共34頁(yè)P(yáng)lasmaureaSecretedandreabsorbedbytubules,freelyfiltratedquick,simplemeasurementwidereferencerange3-8mmol/Lsensitivebutnon-specificindexofillness第14頁(yè)/共34頁(yè)第15頁(yè)/共34頁(yè)Ureaexcretionfilteredatglomerulusabout40%filteredureaisreabsorbedbyrenaltubulesinhealthmoreureaisreabsorbedifrateoftubularflowisslowtubularflowrateisslowwhenthereisrenalhypoperfusion第16頁(yè)/共34頁(yè)IncreasedplasmaureaGIbleedtraumarenalhypoperfusion

decreasedRBF

decreasedECFVacuterenalimpairmentchronicrenaldisease

post-renalobstruction

calculus

tumour第17頁(yè)/共34頁(yè)UreaUsefultestbutmustbeinterpretedwithgreatcareAlwaysconsiderinput,outputandpatient’sfluidvolume第18頁(yè)/共34頁(yè)P(yáng)lasmacreatinine50-140umol/LincreasesinconcentrationasGFRdecreasesanalyticalinterferences(acetoacetate-DKA)NOTproportionaltorenaldamage第19頁(yè)/共34頁(yè)P(yáng)lasmaCreatinineGFR[pCreat]140mL/min0mL/minChangewithinanindividualpatientisusuallymoreimportantthantheabsolutevalue第20頁(yè)/共34頁(yè)P(yáng)lasmacreatinineinchronicrenaldiseaseMayincreaseto1000umol/LPlotofrecipricolofplasmacreatinineconcentrationpredictswheninterventionisrequiredinendstagerenalfailureTime1/[pCreat]第21頁(yè)/共34頁(yè)P(yáng)lasmaUricAcid20%:foods;80%:purinemetabolismSmallamounts:conjugatedwithalbuminFreeFiltrated,98%-100%:reabsorbedPlasmaUAconcentration:dependonglomerularfiltrationandtubularreabsorption第22頁(yè)/共34頁(yè)P(yáng)rogressionofchronicrenaldisease第23頁(yè)/共34頁(yè)P(yáng)lasmaCystatinCCysteineproteinaseinhibitorProducedbynucleatedcellsMW:13000,freefiltration,reabsorbedandmetabolizedbytubulesPlasmaCysCconcentrtion:dependonglomerularfiltration第24頁(yè)/共34頁(yè)Carbamylatedhemoglobin

Urea—blood—cyanate—Hbcarbamylated—CarHbARF：nochanges(1weeks)CRF:increase第25頁(yè)/共34頁(yè)Laboratorytestsofrenalfunctionglomerularfiltrationrateimpracticalcreatinineclearanceunreliableplasmacreatininespecificbutinsensitiveplasmaureasubjecttoproblemsurinevolumeoftenforgotten!第26頁(yè)/共34頁(yè)Section2InvestigationofTubularFunctionDistalnephronFunctiontests1.MosenthaltestConcentrationdilutiontest8AM:VoidingandDiscarded10,12,14,16,18,20:00and8:00nextday:collectingurinesamplesDetermingtheurinevolumeandgravity第27頁(yè)/共34頁(yè)2.UrineOsmolarity3.AcuteOliguriaPrenal?Renal?第28頁(yè)/共34頁(yè)P(yáng)roximaltubularFunctiontests1.LowMWproteinsinurine2.Tubularmaximalglucosereabsorption3.TubularmaximalPAHsecretion4.AminoacideinurineFanconiSyndrome第29頁(yè)/共34頁(yè)Section3EffectiveRenalBloodFlowIsotopeMethod:131I-OIHPAHClearance:20%:filtrated,80%:secretedbytubules第30頁(yè)/共34頁(yè)Section4InvestigationofrenaltubularacidosisTubularAcidosis:I,II,III.IVI:distalformII:proximalform第31頁(yè)/共34頁(yè)NH4ClLoadingTestOraladministrationofNH4ClArtificialMetabolicAcidosisUrineSampleCollectionpHdetermination第32頁(yè)/共34頁(yè)FractionofHCO3-excretion