酸堿平衡醫(yī)學(xué)知識講座2OUTLINE（內(nèi)容提要）BodyFluid（體液）WaterandSodiumDisorders（水鈉失衡）DisturbanceofPotassiumMetabolism（鉀代謝失衡）Acid-baseBalance（酸堿失衡）酸堿平衡醫(yī)學(xué)知識講座3Section1BodyFluidSection1BodyFluid（體液）酸堿平衡醫(yī)學(xué)知識講座4Bodyfluid’sattributes

體液的屬性Volume容積Ingredients:electrolytes成分Osmoticpressure滲透壓Powerofhydrogen酸堿度酸堿平衡醫(yī)學(xué)知識講座5Bodyfluid’sVOLUME（體液的容積）Bodyfluidsconstitute55-60%ofbodymass酸堿平衡醫(yī)學(xué)知識講座6Bodyfluiddistribution（體液的分布）TWOcompartmentsICF細(xì)胞內(nèi)液(2/3TBF,40%TBW)ECF細(xì)胞外液(1/3TBF,20%TBW)Plasma血漿(1/4ECF,5%TBW)Interstitialfluid組織間液(3/4ECF,15%TBW)酸堿平衡醫(yī)學(xué)知識講座7Developmentinbodyfluidproportion

年齡性別的差別AgeNeonate12-14adultTotalfluid80706560ICF35404040ECF45302520Plasma5555Interstitialfluid40252015HigherinyoungHigherinmalesDifferenceinmuscleandfat酸堿平衡醫(yī)學(xué)知識講座8Dailywatergainandloss

每日水的攝入和丟失Watergain1500ml~60%Drink750ml~30%Food150ml~10%metabolicwaterWaterloss1500ml~60%urine600ml~28%sweatandevaporation300ml~8%respiration100ml~4%stoolIndailylife,ahealthadultmanusuallyexchangeabout2500mlofthebodyfluidtotheenvironment.酸堿平衡醫(yī)學(xué)知識講座91532002001541531541421421504534324010103114150273010351635140Bodyfluid’sIngredients:

Electrolytes（電解質(zhì)）Payattention:ThedominatingcationoftheECFisNa+ThedominatingcationoftheICFisK+酸堿平衡醫(yī)學(xué)知識講座10Howtodifferentiatefunctionandnon-functioninterstitialfluids

功能性和非功能性組織間液Function:Takingpartinmodulatingthebalanceofbodyfluids.參與體液平衡調(diào)節(jié)Non-function:Fluidsincavityinnormalstatus.Includingcerebrospinal,joint,pericardiumandabdominalcavityfluids腦脊液、關(guān)節(jié)液、心包夜、腹腔液酸堿平衡醫(yī)學(xué)知識講座11ThirdSpace（第三間隙）Definition:

Pathophysiologically病理生理,relativelynon-functionalextracellularfluid細(xì)胞外液.Mainlyforthechangeofquantityoffunctionalandnon-functionalECF.Distribution:分布

exudatesinburns燒傷滲出;ascites腹水;softtissueinjuries軟組織損傷;bowelwall腸壁水腫;peritoneum腹膜;infectedlesions感染.酸堿平衡醫(yī)學(xué)知識講座12Regulationofwaterandelectrolytes

水電解質(zhì)的調(diào)節(jié)酸堿平衡醫(yī)學(xué)知識講座13OsmoticPressure（滲透壓）OsmosisisthediffusionofwateracrossamembraneHYPERTONIC（高滲的）HYPOTONIC（低滲的）ISOTONIC（等滲的）酸堿平衡醫(yī)學(xué)知識講座14酸堿平衡醫(yī)學(xué)知識講座15酸堿平衡醫(yī)學(xué)知識講座16NormalRange=290~310mOsm/Lcationmmol/Lanionmmol/LNaKCaMg14252.51.5HCO3ClHPO3SO3OrgnicacidProtein2710310.5616Total151Total153.5PlasmaOsmoticPressure

血漿滲透壓酸堿平衡醫(yī)學(xué)知識講座17RelationbetweenOsmoticpressureanddistributionofbodyfluid

（滲透壓與體液分布）

OsmoticPressure：

Crystal（晶體）OPandColloid（膠體）OPPlasmaticCrystalOP:血漿晶體滲透壓

[Na+]contributestoamajorportionofOP酸堿平衡醫(yī)學(xué)知識講座18PlasmaticColloidOP：血漿膠體滲透壓

PlasmaproteincontributesaforceleadingtodistributionofECFInterstitialCrystalOP：組織間隙晶體滲透壓

ContributestotheshiftofextracellularandintracellularwaterRelationbetweenOsmoticpressure

anddistributionofbodyfluid

滲透壓與體液分布酸堿平衡醫(yī)學(xué)知識講座19Regulationofvolume&osmoticpressure

（容量與滲透壓的調(diào)節(jié)）Regulationofbodyfluidgaindependsmainlyonvariationoforalintake

Regulationofbodyfluid(&solute)lossdependsmainlyonurinaryexcretion體液滲透壓調(diào)節(jié)三種機(jī)制酸堿平衡醫(yī)學(xué)知識講座201.Neuralregulation神經(jīng)調(diào)節(jié)

Hypothalamicosmoreceptor下丘腦滲透壓感受器

Hydropenia缺水/overdoseNa+

高鈉Serumosmoticpressure↑血清滲透壓Hypothalamicosmoreceptor(Thirstcenter)

下丘腦滲透壓受體ThirstanddrinkRecovernormal

OsmoticpressureSympatheticnervestimulated刺激交感神經(jīng)酸堿平衡醫(yī)學(xué)知識講座212.Endocrinicregulation內(nèi)分泌調(diào)節(jié)

Hypothalamus-Posteriorpituitary-ADH

下丘腦-垂體后葉-抗利尿激素Dehydration脫水Serumosmoticpressure

血清滲透壓Hypothalamus-Posteriorpituitary-Antidiuretichormone

下丘腦-垂體后葉-抗利尿激素Distalconvolutedtubulereabsorptionofwater↑

遠(yuǎn)曲小管重吸收水NormalOsmoticpressure酸堿平衡醫(yī)學(xué)知識講座223.Renin-Angiotensin-Aldosterone

腎素-血管緊張素-醛固酮系統(tǒng)

Bloodvolume↓Bloodpressure↓Na+sensorinmaculadensaofdistalconvolutedtubuleglomerularcellssecreteRenin

AngiotensinIthenIIArteriolecontractPressurereceptorsinrenalglomerulusSympatheticnerveexcitedZonareticularisofadrenalcortexsecreteAldosteroneNormal

BloodvolumeDistalconvolutedtubulesecreteK+/H+,reabsorbNa+/Cl-/H2O酸堿平衡醫(yī)學(xué)知識講座23Section2WaterandSodiumDisorders

Section2DisordersofWaterandelectrolyte

水電解質(zhì)紊亂酸堿平衡醫(yī)學(xué)知識講座24Classificationofbodyfluidandelectrolytedisorder(FourTypes)

水電解質(zhì)紊亂分類VolumeChanges(ECF)

容量改變

VolumeDeficit；VolumeExcess

ConcentrationChanges濃度改變

Hyponatremia；HypernatremiaMixedvolumeandConcentrationAbnormalities混合改變

ECFDeficitandExcesswithHyponatremiaECFDeficitandExcesswithHypernatremia

CompositionChanges

成分改變

Acid-basedisturbancesPotassium,Calcium,Magnesiumabnormalities酸堿平衡醫(yī)學(xué)知識講座25HYPERTONICWATERDEFICIT高滲性脫水Hypernatremia:

高鈉血癥

[Na+]>145mmol/L酸堿平衡醫(yī)學(xué)知識講座26Etiology(Primary)病因Restrictedwaterintakeandmuchwaterlossincircumstances:水?dāng)z入不足、丟失過多Dysphagia吞咽困難

SweatBurnDiabeticcomaHighfever酸堿平衡醫(yī)學(xué)知識講座27CLINICALMANIFESTATION

臨床表現(xiàn)CharacteristicWaterloss>Na+lossIntracellulardehydrationThirst,myospasm,Classification(waterloss)Mild:2~4%Moderate:4~6%Severe:>6%,braindisorderdecreasedelasticityofskin酸堿平衡醫(yī)學(xué)知識講座28TREATMENT治療Removecauses5%glucose/0.4%NaCl400~500ml/1%lossofBWWater(ml)=?[Na+](examined–normal)(mmol/L)×BW(kg)×4?ofcalculatedvolume+dailyrequirement(2000ml)K+whenurine>40ml/hNaHCO3inacidosis酸堿平衡醫(yī)學(xué)知識講座29ExampleMale,60kg,[Na+]152mmol/LWaterreplenishment(ml)=(152-142)×60×4=2400mlGivinghalfofcalculatedvolumerespectivelyin2daysNa+,K+,acid-baseimbalance酸堿平衡醫(yī)學(xué)知識講座30ISOTONICWATERDEFICIT

等滲性脫水

(Normalsodiumconcentration)酸堿平衡醫(yī)學(xué)知識講座31Etiologies(Acute)病因External-losses:

外部丟失gastrointestinalfluidsduetovomiting，nasogastricsuction，diarrhea,anddigestivetractfistula（消化道瘺）Internal-losses:內(nèi)部丟失sequestration扣押

(ThirdSpace）

Softtissueinjuriesandinfection,burnsIntra-abdominalandretroperitoneal（腹膜后）

inflammationintestinalobstruction,peritonitis酸堿平衡醫(yī)學(xué)知識講座32CLINICALMANIFESTATION

臨床表現(xiàn)Dehydrationsymptom脫水5%ofTBW(20%ofECF)fluidlossShock休克6~7%ofTBW(24~28%ofECF)fluidlossMetabolicacidosis代謝性酸中毒Severeshock酸堿平衡醫(yī)學(xué)知識講座33TREATMENT治療RemovecausesFluidtherapyHypovolemia低血容量:Balancesaltfluid3000mlrapidinfusiontorecoverbloodvolumeNormalvolume正常血容量:1500~2000mlBSFrapidinfusionORIsotonicfluid(ml)=?/NormalHCT×BW(kg)×0.25酸堿平衡醫(yī)學(xué)知識講座34ExampleMale,60kg,HCT54%Isotonicfluid=[(54-48)/48]×60×0.25=1875ml* BSF1.86%Sodiumlactate:Ringer’sfluid=1:21.25%NaHCO3:Isotonicsaline=1:2酸堿平衡醫(yī)學(xué)知識講座35HYPOTONICWATERDEFICIT(低滲性脫水)

Hyponatremia:

低鈉血癥

[Na+]<135mmol/L酸堿平衡醫(yī)學(xué)知識講座36Etiologies(Secondary)病因Continuestodrinkwaterwhilelosinglargevolumesofgastrointestinalfluids.Thelossofalargeamountofsalt,suchasviasweat,andkidney.Inthepostoperativeperiodwhengastrointestinallossesarereplacedwithonlyhypotonicsodiumsolution.

丟鹽多過丟水酸堿平衡醫(yī)學(xué)知識講座37CLINICALMANIFESTATION

臨床表現(xiàn)Mildsodiumdeficit:Symptom0.5gNaCl/Kg,[Na+]<135mmol/LModeratesodiumdeficit:Shock0.5~0.75gNaCl/Kg,[Na+]<130mmol/LSeveresodiumdeficit:Mentalsymptom0.75~1.25gNaCl/Kg,[Na+]<120mmol/L酸堿平衡醫(yī)學(xué)知識講座38TREATMENT治療RemovecausesMildtomoderatesodiumdeficitNaCl(g)=EstimatedNaClloss(g/kgBW)×BW(kg)Example:Male,60kg,[Na+]135mmol/LNaCl=0.5g×60=30g5%GNSinfusion2000ml+dailyrequirement2000ml,nextdayforanotherhalf酸堿平衡醫(yī)學(xué)知識講座39TREATMENTSeveresodiumdeficitRapidreplenishment: Hypertonicsaline(5%NaCl)200~300mlFormularreplenishment: NaCl(g)=?[Na+](Normal–Examined)

(mmol/L)×BW(kg)×0.6(0.5,female)/17*17mmolNa=1gNaCl酸堿平衡醫(yī)學(xué)知識講座40ItiswisetoReplenishalkalinefluidwhenaccompaniedbyacidosis伴酸中毒時補(bǔ)堿1.25%NaHCO3100~200mlBalancedsalinefluid200mlUseCrystal:colloid晶膠比attheratioof2~3:1酸堿平衡醫(yī)學(xué)知識講座41ExampleFemale,55kg,[Na+]118mmol/LNaCl=(142-118)×55×0.50/17=39g1stday:Half(19.5)2/3(13g)≈5%NaCl300ml1/3(6.5)≈0.9%NaCl1000ml2ndday:HalforReassessbymoreexamination酸堿平衡醫(yī)學(xué)知識講座42Compareofthreekindsof

WATERDEFICIT

三種脫水的比較

酸堿平衡醫(yī)學(xué)知識講座43CAUSESHypertonicwaterdeficitIsotonicwaterdeficitHypotonicwaterdeficitGain↓WaterintakedecreasesAcutegastrointestinallossIsotonicdehydrationwithmorewaterplacementLoss↑MuchwaterlossFluidintoinfectedareaContinuallossofgastrointestinaljuiceMajorwoundareachronicexudationExcessexcretionsodiumfromkidney酸堿平衡醫(yī)學(xué)知識講座44PATHOPHYSIOLOGYHypertonicwaterdeficitIsotonicwaterdeficitHypotonicwaterdeficitH2O/Na+balanceWaterloss>Na+lossWaterloss=Na+lossWaterloss<Na+lossWaterflow→ECFECF←→ICF→ICFECF/ICFICF↓ECF↓/ICF↓ECF↓Bloodvolume≈→↓↓↓酸堿平衡醫(yī)學(xué)知識講座45CLINICALMANIFESTATIONHypertonicwaterdeficitIsotonicwaterdeficitHypotonicwaterdeficitMaindeficitwatersodium&watersodiumThirst++-+Nausea&vomiting-+++Myospasm+++-Othostaticgiddiness-+++Bp≈→↓↓↓↓酸堿平衡醫(yī)學(xué)知識講座46LABORATORYEXAMINATIONSHypertonicwaterdeficitIsotonicwaterdeficitHypotonicwaterdeficitUrinevolume↓↓↓-UrinespecificG↑-↓UrineCl--↓↓↓SerumNa+↑Normal↓Pachyhemia血液濃縮≈→↑↑↑↑↑酸堿平衡醫(yī)學(xué)知識講座47TREATMENTHypertonicwaterdeficitIsotonicwaterdeficitHypotonicwaterdeficitFluidinfusionHypotonicsaline/GlucoseIsotonicsaline/BalancedsalineHypertonicsalineFormula:BW(kg)[Na+](mmol/L)H2O(ml)=?[Na+](examined-normal)×BW×4Isotonicsaline(ml)=?/

normal

Hct×BW×0.25Na+(mmol)=?[Na+](normal-examined)×BW×0.60(female0.50)酸堿平衡醫(yī)學(xué)知識講座48

Waterintoxication水中毒

(Dilutushyponatremia稀釋性低鈉血癥)

Retentionofwaterinthebody[Na+]isdecreased

IntracranialpressureisincreasedhighlyManagementStoppinginfusionofwaterDiuresis利尿

Negativebalanceofwater酸堿平衡醫(yī)學(xué)知識講座49IsotonicECFexcess

等滲性細(xì)胞外液過多酸堿平衡醫(yī)學(xué)知識講座50Etiology病因Iatrogenic

醫(yī)源性Secondarytorenalinsufficiency繼發(fā)于腎功能不全MajoroperationSeveretraumaInfectionRenalvascularconstrictionIncreasedADH&Aldosterone

Retentionofsodium&water酸堿平衡醫(yī)學(xué)知識講座51Clinicalmanifestations

臨床表現(xiàn)Circulatoryoverload

Basilarrales（肺底羅音）

HeartfailureTissuesigns

Subcutaneouspittingedema酸堿平衡醫(yī)學(xué)知識講座52Fluid&electrolytetherapy治療Restrictionofwater&sodium

限制水鈉Colloid+Diuretics

膠體+利尿Hypertonicdiuresis:

高滲利尿relievecerebro-edema：20%mannitol減輕腦水腫：甘露醇酸堿平衡醫(yī)學(xué)知識講座53Section3Potassium

PotassiumdisordersDisordersofPotassium,Calcium,Magnesium鉀、鈣、鎂異常Section3酸堿平衡醫(yī)學(xué)知識講座54DisordersofPotassium

鉀代謝異常ThepotassiuminECFconstitutesonly2%oftotalbodypotassium98%potassiumiswithinICFTheserumpotassiumconcentrationisdeterminedprimarilybythepHofECFandthesizeoftheintracelluarK+poolWhenacidosis,anexchangeofintracellularK+forextracellularH+,maycausehyperkalemiaAlkalosishasanoppositeeffect酸堿平衡醫(yī)學(xué)知識講座55Hypokalemia(K+<3.5mmol/L)

低鉀血癥Commoncause

Excessiveexcretion:

排出增加Kidney;Digestivetract(Vomiting,Diarrhea,Gastricsuction,Intestinalfistula)Lessin-take:攝入減少Lessdietaryintake;potassium-freeparenteralfluidsRedistribution

再分布Thetransferofextracellularpotassiumintocells（Alkalosis）酸堿平衡醫(yī)學(xué)知識講座56

2Na+1H+3K+CellH++HCO3-=H2O+CO22Na+1H+3K+酸堿平衡醫(yī)學(xué)知識講座57Clinicalmanifestations

臨床表現(xiàn)General:Anorexia,Nausea,VomitingSkeletalmuscles

(Diminishedtoabsenttendonreflexes,respiratoryhypoventilation)Muscularweakness→Flaccidparalysis(K+

<2.5mmol/L）Smoothmuscles(Paralyticileus麻痹性腸梗阻

)Cardiacmuscles(Hypotension)酸堿平衡醫(yī)學(xué)知識講座58CNS（Serumpotassium＜2.0mmol/L）

Morbus→Obnubilation、disorientation

無力，神志不清，定向障礙Cardiovascular

ECG:STsegmentdepression,decreasedTwave,IncreasedUwave,T<U

Arhythmia:PrematureventricularandatrialcontractionsventricularandatrialtachyarhythmiasClinicalmanifestations酸堿平衡醫(yī)學(xué)知識講座59Diagnosis診斷HistoryClinicalsymptomsSerumpotassium＜3.5mmol/LECG酸堿平衡醫(yī)學(xué)知識講座60Treatment治療ThequantitiesofsupplementalpotassiumSerumpotassium＜3mmol/L.Toreplace200～400mmol，Maybeincreasedby1mmol/LSerumpotassium3～3.5mmol/LToreplace100～200mmol，Maybeincreasedby1mmol/LTherateofadministration(intravenous)Shouldnotexceed20mmolK+

/hr1gKCI=13.4mmolK+

酸堿平衡醫(yī)學(xué)知識講座61

Attention：

Infusionspeed<20mmolK+/h,速度concentration<40mmol/L(KCL3.0g)濃度Calciumnotinfused先不補(bǔ)鈣Treatment酸堿平衡醫(yī)學(xué)知識講座62

Hyperkalemia

高鉀血癥

(K+＞5.5mmol/L）酸堿平衡醫(yī)學(xué)知識講座63Commoncauses病因Excessivepotassiumenteredintobloodcirculation攝入過多----Infusionofexcessivepotassium----InfusionofavastreserveofbloodRenalexcretiondecreased排出減少

----acuterenalfailure----K+retentiondiureticsAbnormaldistribution異常分布----Acuteintravascularhemolysis----Acidosis酸堿平衡醫(yī)學(xué)知識講座64Regulationof[K+]:K+-H+exchange酸堿平衡醫(yī)學(xué)知識講座65Clinicalmanifestations臨床表現(xiàn)Gastrointestinal----Nausea&vomiting----Intermittentcolic&diarrheaParesthesia感覺異常&WeaknessCardiovascular----Bradycardia----Microcirculatorydysfunction(cold,cyanosis,paleandhypotension)酸堿平衡醫(yī)學(xué)知識講座66ClinicalmanifestationsECG--highpeakedTwave--P-Rintervalprolongation--WideningoftheQRScomplex--DepresssionoftheSTsegment---Ventricularasystoleorfibrilation

酸堿平衡醫(yī)學(xué)知識講座67Diagnosis診斷CausesClinicalmanifestationECGSerumpotassiumion>5.5mmol/L酸堿平衡醫(yī)學(xué)知識講座68Treatment治療Withholdingofexogenouslyadministeredpotassium停止攝入Correctionoftheabovecauses糾正病因Anti-arrhythmia抗心律失常

-10%Calciumgluconateinfused酸堿平衡醫(yī)學(xué)知識講座69Loweringofserumpotassium

降低血鉀----Transferpotassiumintocells

（5%NaHCO3;11.2%Sodiumlactate；

50%Glucose+RI,1u/3-4gglucose)----Diuretics----Cation-exchangeresins(oral，clysis)----Peritonealdialysis,orhemodialysis

腹膜或血液透析

Treatment酸堿平衡醫(yī)學(xué)知識講座70Peritonealdialysis,orhemodialysis

腹膜透析，血液透析酸堿平衡醫(yī)學(xué)知識講座71HyperkelamiaECGchange？Effectin10mincalciumgluconateIV.RemovecauseInsulinNaHCO3UrinarysystermurinepotassiumgastrointestinalDecreaseoralionexchangeresin,coloclysishemodialysisyesno酸堿平衡醫(yī)學(xué)知識講座72酸堿平衡醫(yī)學(xué)知識講座73DisordersofCalcium

Hypocalcemia低鈣血癥(<2.0mmol/L)血液中鈣以三種形式存在：與血漿蛋白結(jié)合（40%）、離子鈣（50%）、與磷酸根硫酸根枸櫞酸根結(jié)合(10%)酸堿平衡醫(yī)學(xué)知識講座74HypocalcemiaCauses病因acutepancreatitis胰腺炎;renalfailure;腎衰intestinalfistula;腸瘺Infusionofavastreserveofblood(citricacid)輸入大量庫存血bloodpurification血液凈化

酸堿平衡醫(yī)學(xué)知識講座75Manifestation臨床表現(xiàn)－Symptoms:numbness;麻木

tingling;激動

Apnea;－Signs:HyperactivetendonreflexesChvostek’sSignspositive（輕扣面神經(jīng)時面肌痙攣）

convulsions

酸堿平衡醫(yī)學(xué)知識講座76HypocalcemiaTreatment治療10%calciumgluconate葡萄糖酸鈣5%CalciumChloride氯化鈣酸堿平衡醫(yī)學(xué)知識講座77Hypercalcemia高鈣血癥(>4.0mmol/L)Causes:hyperparathyroidism甲狀旁腺功能亢進(jìn);BonyMetastasis腫瘤骨轉(zhuǎn)移Manifestations:Fatigue;Vomiting；comaTreatment:Enhanceca++excretion;EDTA;Na2SO4;Calcitonin酸堿平衡醫(yī)學(xué)知識講座78Magnesiumdeficiency

低鎂血癥(<0.7mmol/L)Causes:intaking/absorptionManifestations:Pale/excited/Fret焦急Treatment:25%MgSO4酸堿平衡醫(yī)學(xué)知識講座79Hypophosphatemia

低磷血癥

(<0.96mmol/L)Causes:Burn/Pancreatitis燒傷/胰腺炎Manifestations:Emotionaldisturbance情緒障礙Treatment:Glycophosphate，

KH2PO4)及Na2HPO4的混合劑酸堿平衡醫(yī)學(xué)知識講座80Section4

Acid-baseimbalanceAcid-baseimbalance酸堿失衡Section4酸堿平衡醫(yī)學(xué)知識講座81understandingthedatainabloodgaspanelrequiresanappreciationfornotonlyacidsandbases,butalsoventilation,gasexchange,dynamicsofelectrolyteandwatermovement,plasmacomposition,respiratorycontrol,andrenalmechanismsofhydrogenion,electrolyte,andwaterexcretion.“理解血?dú)夥治鰯?shù)據(jù)不僅需要懂得酸和堿平衡，而且要理解通氣，氣體交換，水電解質(zhì)運(yùn)動，血漿成分，呼吸控制，和腎臟的氫離子、電解質(zhì)和水的排泄的機(jī)制。

from:RawsonRE&QuinlanKM,AdvPhysiolEduc2002;26:85-97酸堿平衡醫(yī)學(xué)知識講座82Acid-basebalance酸堿平衡1234酸堿平衡醫(yī)學(xué)知識講座83Keybloodbufferpair

血液緩沖系統(tǒng)Keybufferpair H2CO3

(bufferacid):

HCO3-

(bufferbase)KeybioreactionH++HCO3-←→H2CO3←→CO2+H2O酸堿平衡醫(yī)學(xué)知識講座84酸堿平衡醫(yī)學(xué)知識講座852.Lung:RegulatingCO2

肺的調(diào)節(jié)作用H2CO3<==>CO2+H20酸堿平衡醫(yī)學(xué)知識講座863.Kidney:腎的調(diào)節(jié)作用

RegulatingHCO3-andH+LosingHCO3-=GainingH+/ReabsorbingHCO3-=LosingH+酸堿平衡醫(yī)學(xué)知識講座87Henderson-Hasselbalchequation

NormalrangeofpH:

7.35-7.45PH7.4=40nmolH+/LNormal酸堿平衡醫(yī)學(xué)知識講座88Fourtypesofacid-baseimbalance

四個酸堿失衡類型MetabolicAcidosisMetabolicAlkalosisHCO3-_________H2CO320:1RespiratoryAcidosisRespiratoryAlkalosisH++HCO3-==H2CO3

==CO2+H2O↓↓↑↑酸堿平衡醫(yī)學(xué)知識講座89Changesindifferentacid-basedisturbancesHCO3-PaCO2HCO3-———H2CO3pHMetabolicacidosis↓↓Nor↓↓↓Metabolicalkalosis↑↑Nor↑↑↑RespiratoryacidosisNor↑↑↑↓↓RespiratoryalkalosisNor↓↓↓↑↑酸堿平衡醫(yī)學(xué)知識講座90METABOLICACIDOSIS

代謝性酸中毒

(PrimarilyHCO3-↓pH<7.35)酸堿平衡醫(yī)學(xué)知識講座91CAUSES病因H+

↑frommetabolicorothercauses(AG↑)

代謝或其他因素造成H+產(chǎn)生增加Shock,anoxiaandischemia→lacticacidosisDiabetesmellitus→ketoacidosis酮癥酸中毒RenalexcretingH+dysf.:AcidosisfromdistalconvolutedtubuleHCO3-losses(AGnormal)HCO3-丟失Diarrhea,intestinal,biliary,pancreaticfistulaUreterosigmoidostomy結(jié)腸代膀胱:CL-→ECF,HCO3-→urineRenalreaborptingHCO3-

dysf.:Acidosisfromproximalconvolutedtubule酸堿平衡醫(yī)學(xué)知識講座92AnionGap(AG)陰離子間隙

指血漿中未測定的陰離子(UA)與未測定的陽離子(UC)濃度間的差值

AG =Na+-(Cl-+HCO3-)NormalAG:10~15mmol/L酸堿平衡醫(yī)學(xué)知識講座93CLASSIFICATIONAGnormal:HCO3-losses，increasedinCl-AGincreased:H+productionincreasedfrommetabolicorothercauses

酸堿平衡醫(yī)學(xué)知識講座94PATHOPHYSIOLOGY病理生理學(xué)Lung↑toexpireCO2→PaCO2↓KidneysecreteH+↑&retainHCO3-↑HCO3-:H2CO3-≈20:1酸堿平衡醫(yī)學(xué)知識講座95CLINICALMANIFESTATION

臨床表現(xiàn)RespiratorysystemRapidanddeeprespiration,KetoneodorinexpiredgasCardiovascularsystemReddishflushface,HR↑,Bp↓,arrhythmiaNeuralsystemFatigue,dizziness,somnolence嗜睡,restlessness躁動,comaOthersAcidicurine,renalfailure,shock酸堿平衡醫(yī)學(xué)知識講座96DIAGNOSIS診斷HistoryClinicalmanifestationArterygasanalysisDecomp.:Partialdecom.:酸堿平衡醫(yī)學(xué)知識講座97TREATMENT治療Removecauses祛除病因Correctdehydration糾正脫水GiveNaHCO3碳酸氫鈉酸堿平衡醫(yī)學(xué)知識講座98NaHCO3therapyMildacidosis(HCO3->16~18mmol/L)UnnecessarySevereacidosis(HCO3-<10mmol/L)HCO3-

(mmol)=?

[HCO3-](Normal-Examined)

(mmol/L)×BW(kg)×0.4 *HCO3-=22~27mmol/L,Mean24mmol/L *5%NaHCO3100ml=60mmolHCO3-酸堿平衡醫(yī)學(xué)知識講座99ItiswisetoDilute5%NaHCO3to1.25%Give?ofcalculatedvolumeandreassessGiveCa2+

(hypocalcemiainalkalosis→tetania)GiveK+酸堿平衡醫(yī)學(xué)知識講座100Case1–PatientwithSevereAbdominalPain

嚴(yán)重腹痛酸堿平衡醫(yī)學(xué)知識講座101Case1–PatientwithSevereAbdominalPain

Anobese70yearoldmanhasdiabetesof25yearsdurationcomplicatedbycoronaryarterydisease(CABGx4vessels10yearsago),cerebrovasculardisease(carotidarteryendarterectomy3yearsago)andperipheralvasculardisease(Aorto-bifem2yearsago).[“VASCULOPATH”]肥胖、老年、糖尿病、血管病變酸堿平衡醫(yī)學(xué)知識講座102Case1–PatientwithSevereAbdominalPain

Henowpresentstotheemergencydepartmentwithsevere,poorlylocalisedabdominalpainwitharelativelysuddenonset.嚴(yán)重腹痛、定位不清Tothesurpriseoftheinternthatexamineshim,thepatienthasarelativelynormalabdominalexamination.Justlotsandlotsofpain.Norhasthepatienthadvomiting,diarrhea,orotherGIsymptoms.

腹部體征不明顯酸堿平衡醫(yī)學(xué)知識講座103Case1–PatientwithSevereAbdominalPainTheinternconsidersthedifferentialdiagnosisofsevereabdominalpaininthesettingofadiabeticvasculopathwithoutmuchinthewayofabdominalsigns.Shewondersifthismightbeanothermanifestationofvasculardisease.FollowingaGooglesearchshefindsthefollowingstatementat:Thesinequanonofmesentericischemia腸系膜血管缺血

isarelativelynormalabdominalexaminationinthefaceofsevereabdominalpain.

腹痛嚴(yán)重腹部體征相對不明顯酸堿平衡醫(yī)學(xué)知識講座104Case1–PatientwithIschemicBowel腸缺血Followingdiscussionwithherattending,thepatientistobeadmittedtoaregularnursingfloorwhereheistobeworkedupforhisabdominalpain.However,hemustremainintheemergencydepartmentuntilabedcanbefound.收入院，急診科待床Whentheinterncomesby3hourslatertorecheckonthepatienthelooksmuchworse.Henowhasabdominaldistention,ileus(nobowelsounds),andsignsofshock(BP75/45).3小時后腹脹、腸梗阻、休克HeisrushedtotheIntensiveCareUnit(ICU).入ICU酸堿平衡醫(yī)學(xué)知識講座105Case1–PatientwithIschemicBowel

酸堿平衡醫(yī)學(xué)知識講座106BurnsBJ,BrandtLJ.Intestinalischemia.

GastroenterolClinNorthAm.2003Dec;32(4):1127-43.

Ischemicinjurytothegastrointestinaltractcanthreatenbowelviabilitywithpotentialcatastrophicconsequences,includingintestinalnecrosisandgangrene.Thepresentingsymptomsandsignsarerelativelynonspecificanddiagnosisrequiresahighindexofclinicalsuspicion.Becausemostlaboratoryandradiologicstudiesarenonspecificinearlyischemiaanaggressiveapproachtodiagnosiswithimagingofthesplanchnicvasculaturebymesentericangiographyisadvocated.腸系膜血管造影確診酸堿平衡醫(yī)學(xué)知識講座107Case1–PatientwithIschemicBowel

Mortalityratesof70-90%havebeenreportedwithtraditionalmethodsofdiagnosisandtherapy;however,amoreaggressiveapproachmayreducethemortalityrateto45%.Asurvivalrateof90%maybeobtainedifangiographyisobtainedpriortotheonsetofperitonitis.傳統(tǒng)診斷治療死亡率高，早期積極血管造影降低死亡率酸堿平衡醫(yī)學(xué)知識講座108Case1–PatientwithIschemicBowel

ABGs（血?dú)夥治觯﹐btainedintheICUpH 7.18PCO220mmHgHCO37mEq/LWhatistheprimarydisorder?Whatisthephysiologicresponsetothisdisorder?酸堿平衡醫(yī)學(xué)知識講座109Case1–PatientwithIschemicBowel

Forametabolicdisturbance,istherespiratorysystemcompensatingOK?

"Winter'sformula": ExpectedPCO2inmetabolicacidosis

=1.5xHCO3+8(range:+/-2) =1.5x7+8=18.5

pH 7.18PCO220mmHgHOC37mEq/L酸堿平衡醫(yī)學(xué)知識講座110AnionGap==135-98-7mEq/L=30mEq/L(ELEVATED)

SERUMELECTROLYTEDATASerumsodium 135 mEq/LSerumbicarbonate 7 mEq/LSerumchloride 98 mEq/LAnionGap=SerumSodium–SerumChloride–SerumBicarbonate

酸堿平衡醫(yī)學(xué)知識講座111Case1–PatientwithIschemicBowel

“Primarymetabolicacidosis,withincreasedaniongap,withfullrespiratorycompensation”原發(fā)性代謝性酸中毒，伴陰離子間隙增加，完全呼吸代償酸堿平衡醫(yī)學(xué)知識講座112METABOLICALKALOSIS

代謝性堿中毒

(PrimarilyHCO3-↑pH>7.45)酸堿平衡醫(yī)學(xué)知識講座113CAUSES病因H+loss:gastricjuicesuctionOverintakeofalkalineHypokalemiaICF3K+

→←ECF2Na++1H+alkalosisUnusualacidicurine:excretesmoreH+&reabsorbsmoreHCO3-

DiureticCl-↓Furosemide→Cl-loss→Na+,HCO3-reabsorption↑→Alkalosis酸堿平衡醫(yī)學(xué)知識講座114Alkalosis:HypokalemiaduetoK+-H+exchange

AlkalosisHypokalemiaLowserumleaveexchangeintomorecellLow酸堿平衡醫(yī)學(xué)知識講座115PATHOPHYSIOLOGYLung↓toexpireCO2→PaCO2↑KidneysecreteH+↓&retainHCO3-↓HCO3-↑

:H2CO3-↑≈20:1酸堿平衡醫(yī)學(xué)知識講座116OHDCshiftleftinalkalosisOxyhemoglobindissociationcurveshiftleftHbO2donotreleaseO2Tissueanoxia“Preferacidicratherthanalkaline”“寧酸勿堿”酸堿平衡醫(yī)學(xué)知識講座117CLINICALMANIFESTATION

臨床表現(xiàn)Breath:shallow&slowNeuropsychicsymptom:delirium譫妄,psychicconfuse,somnolence困倦,coma酸堿平衡醫(yī)學(xué)知識講座118DIAGNOSIS診斷HistorySymptomsuspiciousArterygasanalysisDecomp.:Partialdecom.:+K+↓+Cl-↓酸堿平衡醫(yī)學(xué)知識講座119TREATMENT治療RemovecausesFluidreplenishmentGiveIS/GNStocorrecthypochloremiaGiveK+tocorrecthypokalemiaHCltherapyForseverealkalosis(HCO3-45~50mmol/L,pH>7.65)酸堿平衡醫(yī)學(xué)知識講座120HCltherapyHCl(mmol)=?HCO3-

(Examined-expected)(mmol/L)×BW(kg)×0.4HCl(mmol)=?Cl-

(Normal-examined)(mmol/L)×BW(kg)×0.6×0.2IsotonicHCl12mmol/LHCl20ml+H2O→0.2mmol/LHCl1200ml+10%GS1200ml→0.1mmol/LHCl2400ml→Centralveins酸堿平衡醫(yī)學(xué)知識講座121ItiswisetoHalf1stdayMildreplenishmentMonitorurine[Cl-]酸堿平衡醫(yī)學(xué)知識講座122A23-year-oldwomanis12weekspregnant.Forthelastwith10daysshehashadworseningnauseaandvomiting.Whenseenbyherphysician,sheisdehydratedandhasshallowrespirations.Arterialbloodgasdataisasfollows: pH 7.56

PCO2 54mmHg

Case2–PregnantWomanwithPersistentVomiting

妊娠伴持續(xù)嘔吐酸堿平衡醫(yī)學(xué)知識講座123

DIAGNOSISMetabolicAlkalosisfromPersistentVomiting

pH 7.56

PCO2 54mmHg酸堿平衡醫(yī)學(xué)知識講座124

妊娠惡心嘔吐極為常見.惡心、嘔吐發(fā)生率66-89%和38-57%.一般9-10周開始o(jì)f,11-13周最嚴(yán)重,50%在12-14后緩解.約1-10%孕婦,癥狀持續(xù)超過20-22周.

最嚴(yán)重的妊娠惡心嘔吐稱為妊娠劇吐癥

（hyperemesisgravidarum，HEG).HEG的特征是持續(xù)惡心嘔吐伴堿中毒和體重下降(>5%)，可引起血容量丟失