Water and electrolyte disorders 一、水、电解质代谢的生理基础一、水、电解质代谢的生理基础 (一一)体液体液1.体液及其分布体液及其分布IntracellularfluidTotal(ICF)40%(60%)interstitialfluid15%extracellularfluidplasma5%(ECF)20%transcellularfluid2%(透细胞液透细胞液) 2.体液中主要电解质及其分布体液中主要电解质及其分布 extracellularfluid:Na+、Cl-、HCO3-intracellularfluid：K+、HPO42-在在Na+-K+-ATPase作用下，细胞内外作用下，细胞内外Na+、K+保持不对等分布保持不对等分布。 3.Osmoticpressureofbodyfluid(plasma) Positiveion:151mmol/L Negativeion:139mmol/Ltotal280-310mmol/LNonelectrolyte:10mmol/L(678.3kpa) Plasmacolloidalosmoticpressure:3.72kpa(28mmHg) （二）（二）movementofwaterandelectrolytes1.plasmainterstitialfluidcapillaryprotein2.intra-andextra-cellularfluidproteinsandpositiveion:permeabilitywaterandnegativeion:permeability(watermovementbalanceofosmoticpressure)RBC 3.Balanceofbodywaterandsodium drink 1200mlwaterintakefood1000ml(2000-2500ml)oxidation300mlbalanceofwaterurine1200-1500mlwaterlossskin500ml(2000-2500ml)respiration350mlfeces150mlBalanceIntake/d100-200mmol(digestivetract)of sodium Loss/d 100-200mmol (urinarysystem) ECF:50% ECF:50%Distribution ICF: 10% ICF: 10% ofsodium 骨基质骨基质:40% (:40% (正常血清钠正常血清钠: :130-150mmol)(三三)RegulationofosmoticpressureandvolumeHypertonicthirstofECF1.bodywaterADH;aldosteronesodiumthirstAngADHbodyvolumealdosteronereceptorofvolumeADH2.bodywatersodiumADHreabsorptionofsodium3.bloodvolumeANPaldosterone(ADS)tension4.othersADHpainFigure:regulationofADHsecretion osmoticpressureR pressureR ADH volumeRheart二、二、waterandsodiumdisorders hypertonichypertonicdehydrationisotonicwaterexcessisotonichypotonichypotonic(一一)细胞外液容量不足细胞外液容量不足(extracellularfluiddeficit) 1.Hypotonicdehydrationsodiumlosswaterlossserumsodium130mmol/L plasmaosmoticpressure 280mOsm/L 280mOsm/L 1)causeandPathogenesisexcessivelossofwaterandsodiumreplacedwithwateronly.vomiting,diarrhea;burn;diuretics;Addisonsdisease(ADS);chronicrenalfailure;renaltubularacidosis2)adaptiveresponseandeffectonbodymovementofbodyfluidECFICFcellularswellingBloodvolumeExtracellularfluidShockdehydratedsignsedemaofbrainandlungurinaryalterationurinespecificurinevolumegravityNa+-earlyADHorstageADSlateADHstageADS-(注：经肾失钠的低渗性脱水，尿钠不减少注：经肾失钠的低渗性脱水，尿钠不减少) 3)principlesoftreatmenttreatingprimarydisease0.9%NaCl2.hypertonicdehydrationwaterlosssodiumloss serumsodium150mmol/L plasmaosmoticpressure310mOsm/L1)causeandpathogenesislackofwater(desert;sea) intaketodrinkinability(coma;baby)lung:hyperpnea(hypoxia;acidosis) skin:fever;hyperthyroidism;sweat;exposuretohotenvironmentlossdigestivetract:vomiting;diarrhea;babydiarrhea(Na+:60mmol/L)kidney:diabetes(ketosis);diabetesinsipidus diuretic(mannitol;hypertonicglucose) 2)effectonbody hypertonicofECFthirst movementofthebodyfluidICFECFcelldehydrationBraindehydrationSleepinesssubarachnoidspacebleedingDehydrationofsweatglandsdehydratedfeverdehydrationofheatregulatingcenter urinaryalterationurinespecificurinevolumegravityNa+-earlyADHstageADSlateADHstageADS-3)principlesoftreatment 先水，后盐；补水大于补钠。先水，后盐；补水大于补钠。 病例病例1 1：患者，男性，：患者，男性，4040岁，吐、泻伴发热、口渴、尿岁，吐、泻伴发热、口渴、尿少少4 4天入院。天入院。 体格检查：体温体格检查：体温 38.238.2，血压，血压 110/80mmHg110/80mmHg，汗，汗少，皮肤黏膜干燥。少，皮肤黏膜干燥。 实验室检查：血实验室检查：血Na+ 155mmol/LNa+ 155mmol/L，血浆渗透压，血浆渗透压320mOsm/L320mOsm/L，尿比重，尿比重1.020。给予给予5%葡萄糖溶液葡萄糖溶液2500ml/d和抗生素，和抗生素，2天后体天后体温、尿量正常，口不渴，眼窝凹陷，皮肤弹性明显温、尿量正常，口不渴，眼窝凹陷，皮肤弹性明显降低，无力，肠鸣音减弱，腹壁反射消失。浅表静降低，无力，肠鸣音减弱，腹壁反射消失。浅表静脉萎陷，脉搏脉萎陷，脉搏110次次/分，血压分，血压72/50mmHg，血，血Na+120mmol/L，血浆渗透压，血浆渗透压255mOsmmOsm/L，血，血K+3.0mmol/L3.0mmol/L，尿比重，尿比重1.0101.010，尿钠，尿钠8mmol/L8mmol/L。3.isotonicdehydration waterlosssodiumloss serumsodium= =130-150mmol/L plasmaosmoticpressure:280-310mOsm/L1)causeandpathogenesis vomiting;diarrhea;gastrointestinalsuction;biliaryfistula;intestinalfistula asciticfluid;pleuraleffusion 2)effectsonbody slightthirst bloodvolumedehydratedsigns;BP urinaryalterationurinespecificurinevolumegravityNa+-earlyADHstageADSlateADHstageADS-3)principlesoftreatment补偏低渗液；先补补偏低渗液；先补0.9%NaCl病例2： 患者，女性，38岁，因减肥连续服用泻药一周，现感虚弱乏力，偶有直立性眩晕而入院。 体格检查：体温36.7，血压从入院时的110/60mmHg 很快降至 80/50mmHg，心率 100次/分，皮肤弹性差，黏膜干燥，尿量120ml/24h。 实验室检查：血Na+ 140mmol/L，血浆渗透压295mOsm/L，尿比重 1.038，尿钠 6mmol/L。( (二二) ) 细胞外液容量过多细胞外液容量过多(extracellularfluidexcess)1.waterintoxicationwaterintake,totalsodium;ECF,ICF;hyponatremia;Serumsodium130mmol/L1)cause excessivewaterintakerenalloss(acuterenalfailure;acutecongestiveheartfailure)2)effectsonbodybraincellsswellingwatermovesintocellspulmonaryedema3)principlesoftreatment diuresis病例3：患者，女性，因外伤急救误输异型血 200ml后，出现黄疸和无尿。 体格检查：体温37，脉搏 80次/分，呼吸 80次/分，血压从入院时的110/60mmHg 很快降至 80/50mmHg。神志模糊，表情淡漠，皮肤黏膜干燥、黄染，静脉塌陷。 实验室检查：血清尿素氮 15.0mmol/L，非蛋白氮 57.12mmol/L，血 K+ 6.7mmol/L。 入院后急速输入5%10%葡萄糖溶液1500ml，生理盐水500ml后，当晚做血液透析，透析中血压上升并稳定在110140/70mmHg，透析后查尿素氮为 9.46 mmol/L，非蛋白氮 44.3mmol/L，血 K+ 5.7mmol/L。 患者5天内一直无尿，并逐渐出现明显气喘、心慌、不能平卧，嗜睡、呕吐、头痛、精神错乱症状。查体发现，心率 120次/分，两肺布满湿罗音。血 Na+ 120mmol/L，血浆渗透压 230mOsm/L，红细胞比容 32%。 2.Edemainterstitialfluidfluidinthebodycavitieshydropsfluidinthecellscellularedema(1)pathogenesis1)imbalanceofexchangebetweenintra-andextra-bodyfluid(retentionofwaterandsodium)basicmechanism:glomerular-tubularimbalanceGFRacuteglomerulonephritisheartfailure reabsorptionofproximaltubulesympatheticnervefiltrationfractionANPreabsorptionofwaterandsodium reabsorptionofdistaltubuleADH,aldosterone redistributionofrenalbloodflowsympatheticnervesandrenin2)imbalanceofexchangebetweenintra-andextra-vascularfluid capillarybloodpressureplasmacolloidosmoticpressurepermeabilityofcapillaryobstructionoflymph3)kindsofedema3.盐中毒盐中毒病例4：患者，女性，因发热、呼吸急促及心悸入院。 体格检查：体温39.6，脉搏 161次/分，呼吸 33次/分，血压 110/80mmHg. 口唇发绀，半卧位，颈静脉怒张，心界向两侧扩大，心尖区闻及明显收缩期杂音，两肺闻及广泛湿罗音。肝脾肿大，下肢明显凹陷性水肿，入院诊断为右心衰竭。