dysnatremias: hypernatremia and polyuria · • hypernatremia / hyponatremia reflects free water...

Dysnatremias:HypernatremiaandPolyuria

AstoryofwaterandvolumeElaineM.Kaptein,MDekaptein@usc.edu

Nodisclosures

OBJECTIVES

•  Physiology/pathophysiologyoftotalbodywaterandvolume

•  Evaluationandtreatmentofhypernatremia•  Sodiumconcentrationsofbodyfluidlossesandparenteralandenteral“fluid”inputstoestimatewaterandvolumecomponents

•  Challengesinassessingintravascularvolume•  Applythisinformationtotheclinicalsetting

RegulationofTotalBodyWaterandSodium

WATER:Antidiuretichormone(ADH)

-Stimulatesthirstandrenalwaterreabsorption-Increasedbyhyperosmolality,hypothalamic hypoperfusion,nausea,vomiting,stressand narcotics

-decreasedbyhyponatremiaINTRAVASCULARVOLUME:Renin-Angiotensin-Aldosterone(RAAS)

-Stimulatessodiumreabsorptionbythekidney-Increasedbyrenalhypoperfusion-Decreasedbyhypervolemia,ACEI,ARBs,Spironolactone

DistributionofTBW

Proportions given for 70kg male1, may vary in illness2.

1.  Randall HT. Water and electrolyte balance in surgery. The Surgical Clinics of North America. 1952: 445-469. 2.  Randall HT. The shifts of fluid and electrolytes in shock. Annals of the New York Academy of Sciences. 1952; 55: 412-428

SODIUM POTASSIUM

Plasma ECF

Normalconditions

MJKaptein,MD

SerumSodiumConcentration

Serum[Na+]=exchangeablebody(sodium+potassium)totalbodywater=amountofsodium/volumeofECFwaterNormalserum[Na+]is140mEq/LofserumNormalsalineis154mEq/LofwaterWHY?Only91%ofserumiswater

HYPERNATREMIAS[Na+]>145mEq/L

S[Na+]canbemeasuredby1)  AutoanalyzerforBMP2)  FlamephotometerforABGorVBGQUESTIONS:1)Aretheyalwaysthesame?No.WHY?2)CanpseudohypERnatremiaoccur?

Normal plasma

95% plasma

water

5% protein/lipid

91% plasma

water

9% protein/lipid

Hypoproteinemic plasma

Pseudohypernatremia

Na 154 Na

154

Apparent concentration of Na in serum by indirect method (BMP)

154 x 0.91 = 140mEq/L of serum 154 x 0.95 = 146 mEq/L of serum

S[Na+] is “normal” if measured directly with ion-sensitive electrodes in undiluted PLASMA in the ABG lab in the presence of low protein and lipids.

PseudohypERnatremia•  Lowserumproteinconcentrationsincreasethewaterphaseofserumto>91%andcanresultinanartifactualincreaseofserum[Na+]byindirectpotentiometry(BMP)comparedtodirectpotentiometry(ABG/VBG).

•  >4mEq/Ldifferencein25%ofICU,8%ofhospitalizedspecimens

•  97%with>4mEq/Ldifferencewereduetolowproteinconcentrations.

•  JCritCare27:326.e9-e12,2012

PseudohypernatremiainourICU(PaulLoener,MDRegionalACP2014)

•  30ICUpatientswithtotalproteinconcentrations<6g/dL

•  Serum[Na+]byBMPgreaterthanonABGin29of30patients.

•  30%haddifferencesof>4mEq/LSIGNIFICANCE:FreewaterreplacementshouldbecalculatedusingdirectISEmethodstoavoidovercorrectionandhyponatremia.

DiagnosticApproachtoHypernatremia•  AssessforPseudoHYPERnatreima(overestimatingS[Na+])CompareS[Na+]byBMPwithVBG/ABGS[Na+]maybeHIGHERonBMPthanVBG/ABGduetohypoproteinemia/hypolipidemiaincreasing%serumwater

CORRECTS[Na+]VALUEisviaVBG/ABG•  AssessforHyperosmolarstates-watershiftsfromICFto

ECFwithincreasedglucose,mannitolorcontrastDecreaseinS[Na+]=2x(Serumglucose-100)/100

e.g.Ifserumglucoseis900,2x(900-100)/100=8x2=16,soS[Na+]isactually16mEq/LhigherthanonVBGorABGwhencorrectedforwatershiftduetohyperglycemia

CausesofHypernatremia

Freewaterintake<freewaterlosses or

AdministrationofhypertonicsodiumsolutionsResultinginatotalbodyfreewaterdeficitrelativetototalbodyexchangeablesodium

HYPERNATREMIATREATMENT1.  Recognizeandcorrectunderlyingproblem2.  Calculatethefreewaterdeficit5.  Replace1/2offreewaterdeficitin24hours.

Nottodecreaseserum[Na+]>0.5mEq/L/hror8-10mEq/L/dtoavoidcerebraledema

7.  Replaceongoingwaterlosses-insensiblelosses-GIlosses-renallosses5.Maintaineuvolemia.

HYPERNATREMIATREATMENT1.   Recognizeandcorrectunderlyingproblem2.  Calculatethefreewaterdeficit5.  Replace1/2offreewaterdeficitin24hours.

Nottodecreaseserum[Na+]>0.5mEq/L/hror8-10mEq/L/dtoavoidcerebraledema

7.  Replaceongoingwaterlosses-insensiblelosses-GIlosses-renallosses5.Maintaineuvolemia.

HYPERNATREMIACLINICAL CIRCUMSTANCES

Elderly/InfantsAMS

Decreased ThirstUnable to drinkReset osmostat

Central Nephrogenic

Diabetes Inspidus

Pure waterlosses

Renal, GIlung, skin

Water loss > Na loss

Hypotonic losses HypertonicNa Bicarbonate

3% SalineTPN

Renal•  Purewaterlosses-DI•  Osmoticdiuresis-glucose,

contrast,mannitol,urea,diuretics–  Losses~1/2normalsaline(Ur[Na+]~80mEq/L)–  Alwayscheckurine[Na+]

Non-renal•  GI:

–  Gastric–  Osmoticdiarrhea:sorbitalor

lactulose

•  SWEAT•  RESPIRATION

Hypotonic“fluid”lossesWater losses > sodium losses

POLYURIA

Definition:

Urineoutput>3liters/day

CAUSESOFPOLYURIA

•  OSMOTIC-uncontrolleddiabetesmellitus-ioniccontrast,mannitol,

electrolytes•  WATER-psychogenicpolydispsia-centraldiabetesinsipidus-nephrogenicdiabetesinsipidus

PRIMARYPOLYDIPSIA

Aprimaryincreaseinwaterintake•  Inpsychiatricillnesses+/-phenothiazines•  Hypothalamiclesionsofthethirstcenter

–  infiltrativediseasesuchassarcoidosis MaycausehyponatremiaIfwaterintake=waterlosses,S[Na+]unchangedIfwaterintake>waterloses,S[Na+]decreases

CENTRALDIABETESINSIPIDUS

Deficientsecretionofantidiuretichormone•  Familial •  Idiopathic-mostoften(?autoimmuneinjurytotheADH-producingcells)

•  Acquired-trauma,pituitarysurgery,orhypoxicorischemicencephalopathyIfwaterlosses=waterintake,S[Na+]unchangedIfwaterlosses>waterintake,S[Na+]increases

NEPHROGENICDIABETESINSIPIDUS•  Familial•  Aquired

–  RenalMedullaryDiseasesObstructiveuropathyAnalgesicnephropathyMedullarycysticdiseaseSicklecelldisease

– MetabolicDisorders-Chronichypokalemia, -Hypercalcemia

– Drugs:Lithium,demeclocycline,foscarnat,cidofovir

Ifwaterlosses=waterintake,S[Na+]unchangedIfwaterlosses>waterintake,S[Na+]increases

POLYURIAWater diuresis

Psychogenicpolydipsia

Decreased

Central DINo ADH

Nephrogenic DIHigh ADH

Increased

Serum Osmolality

POLYURIADefinition: >3 liters of urine/day

Do Water deprivation testif Sosm <300

U/P osm <0.7

Urine OsmHypotonic to serum

Pure water

>0.6 =electrolyteSaline

Bicarbonate

<0.4 =nonelectrolyteGlucose, Urea

Mannitol, Contrast

Electrolyte fraction=2(UNa+UK)/Uosm

U/P osm >0.8

Urine OsmIsotonic (300 mOsm/kg)

Osmotic

Complete:Increase>50%Partial:Increase>10%

DifferentiationofPolyuria Osmotic

diuresis Primary Polydipsa

Central DI Nephro DI

Posm Increased Decreased Increased Increased Uosm Isotonic Decreased Decreased Decreased Plasma AVP

Increased Decreased Decreased Increased

Uosm with Dehydration

No effect Increased No effect No effect

Uosm after AVP

No effect No effect Increased No effect

TherapyofDiabetesInsipidus

•  CENTRALDI:DDAVP10-20UINq12-24hrsChlorpropamide,clofibrate,carbamazepineplusAPPROPRIATEFREEWATERINTAKE•  NEPHROGENICDI:HCTZ/Amiloride,sodiumandproteinrestriction(decreasedosmolarload),?NSAIDsplusAPPROPRIATEFREEWATERINTAKE.

•  PSYCHOGENICPOLYDIPSIA:Decreasefreewaterintake

HYPERNATREMIA

•  CALCULATEFREEWATERDEFICIT– S[Na+]x0.5(TBwt)=140mEq/lxnewTBW

•  Replaceongoinglosses–  Insensible– Sensible

HYPERNATREMIATREATMENT1.  Recognizeandcorrectunderlyingproblem2.  Calculatethefreewaterdeficit5.  Replace1/2offreewaterdeficitevery24hours.Donotdecreaseserum[Na+]>0.5mEq/L/hror8-10mEq/L/dtoavoidcerebraledema4.  Replaceongoingwaterlosses-insensiblelosses-GIlosses-renallosses5.Maintaineuvolemia.

HYPERNATREMIA•  CALCULATEFREEWATERDEFICIT

–  S[Na+]x0.5(TBwt)=140mEq/lxnewTBW

Thepatientisa65yearoldfemale,founddown.Weight60kgS[Na+]165mEq/LSerumglucose75mg/dLSerumtotalprotein7.5g/dLNocontrastormannitolgivenTBW=0.5xTBwt=0.5x60kg=30litersS[Na+]x0.5(TBwt)=140mEq/lxnewTBW165x30/140=35.4liters=theTBWifS[Na+]were140mEq/LFreewaterdeficit=35.4-30liters=5.4liters

•  Replace½thefreewaterdeficitin24hours(2.7L)nottodecreaseS[Na+]morethan8-10mEq/Lin24hourswithFREEWATERPOorIV

HYPERNATREMIATREATMENT1.  Recognizeandcorrectunderlyingproblem2.  Calculatethefreewaterdeficit3.Replace1/2offreewaterdeficitin24hours.Donotdecreaseserum[Na+]>0.5mEq/L/hror8-10mEq/L/dtoavoidcerebraledema

4.  Replaceongoingwaterlosses-insensiblelosses-GIlosses-renallosses5.Maintaineuvolemia.

PROBLEM

Net“fluid”balanceandchangesintotalbodyweightreflectchangesinvolumeandwaterandareNOTuseful.Determiningongoingwaterandsodiumrequirementsinhospitalizedpatientsremainsdifficultsincesodiumconcentrationsofmostbodyfluidlossesareneitherknownorroutinelymeasured.

Sodiumconcentrationsofbodyfluids:Asystematic

literaturereview

KapteinEM,SreeramojuD,KapteinJS,KapteinMJClinicalNephrology2016

Sodium concentrations of body fluids: A systematic literature review

Kaptein EM, Sreeramoju D, Kaptein JS, Kaptein MJ

Clinical Nephrology October, 2016

Knowspecificsodiumandwatercontentof-Bodyfluidlosses,and-ParenteralandenteralfluidsadministeredUsethisinformationto1)replacesodiumandwaterlossesofspecificbodyfluidstominimizedevelopmentofwaterandvolumedisorders,and2)prescribeappropriatetherapyfor

hypo-andhypernatremia,andfor hypo-andhypervolemia.

Goals

•  Systematicsearchandliteraturereviewof[Na+]ofbodyfluidslostinadulthumans–  PubMeddatabase–  Searchingrelatedreferences

•  Reviewed>7,000titles,abstracts,full-textarticles•  Inclusioncriteria:

–  Peer-reviewed,extractablesodiumconcentrationsmeasuredinbodyfluidswhoselossesareroutinelyquantifiedinhospitalizedpatients.

Methods

MJKaptein,MD

Results •  107full-textarticleshadextractablesodiumconcentrations.

Overallmeansandstandarddeviations(SDs)areshownfrom84studieswithrawdataormeansandSDs.

•  Sodiumconcentrationsarefluid-specificandconsistent.•  Gastric[Na+]withhighacid(44+12mEq/L)vs.lowacid

(55+13mEq/L)wasstatisticallybutnotclinicallydifferent.•  Sodiumconcentrationsofdiarrheaaremechanismspecific.•  Pleural,peritoneal,andedemafluid,areisonatremicto

plasma,asareultrafiltratesofplasmawithhemodialysisandperitonealdialysis,sinceallarederivedfromplasma.

•  Nodatawerefoundforwoundsorlymph(isonatremic).

MJKaptein,MD

Meansodiumconcentrationsofbodyfluidlosses

NS

SodiumconcentrationsofbodyfluidlossesBodyFluid [Na+]mEq/L Normalsaline(%) Water(%)

Gastric 50 33 67

Bile 185 100 0

Pancreatic 156 100 0

Smallbowel 120 75 25

DIARRHEA

cholera 128 85 15

non-osmoticlaxatives 88 50 50

secretorydiarrhea 53 33 67

sorbitol 63 40 60

lactulose 26 15 85

polyethyleneglycol 15 10 90

Pleural,peritoneal,dialysate,(wounds) 137 100 0

Sodiumconcentrationsofparenteralandenteralsolutions

ThesearepharmaceuticalsCHECK[Na+]foreachsolutionDivideby154mEq/LtoassessproportionofNSandH20

Background

Proportions for a 70kg male1, may vary in illness2

1) Randall HT. Water and electrolyte balance in surgery. The Surgical Clinics of North America. 1952: 445-469. 2) Randall HT. The shifts of fluid and electrolytes in shock. Annals of the New York Academy of Sciences. 1952; 55: 412-428

•  RBCsstayintravascular.•  Isonatremicsolutions

equilibrateacrosstheECF(IVplusEV).

•  Hypervolemiaorhypovolemiareflecttotalbodysodiumexcessordeficit.

•  Freewater(FW)equilibratesacrossbothECFandICF.

•  Freewatergain/lossprimarilyaffectsserum[Na+].

•  Hypernatremia/hyponatremiareflectsfreewaterdeficitorexcess.

MJKaptein,MD

Background

Proportions for a 70kg male, may vary in illness 3) Konstam MA, Gheorghiade M, Burnett JC, Jr., Grinfeld L, Maggioni AP, Swedberg K, Udelson JE, Zannad F, Cook T, Ouyang J, Zimmer C, Orlandi C: Effects of oral tolvaptan in patients hospitalized for worsening heart failure: The everest outcome trial. JAMA 2007;297:1319-1331 2007;297:1319-1331

•  EVERESTtrialusingavaptantoblockrenalADHeffectshowed4.5literaquaresisdidnotchangeCHFmorbidityormortality3,suggestingfreewaterhasminimalvolumeeffect.

•  Hyponatremiawasimproved.•  Conclusion: water is not volume •  [Na+]ofallfluidslostandgained

canbedividedby[Na+]ofplasmawater(normally154mEq/L)todeterminewhatproportionwilldistributeasisonatremicsolution.

MJKaptein,MD

ENTRIESINYELLOWAREAS gain/lossNS(mL) gain/lossH2O(mL)

ONLY(aspositivevalues)(use"Space,Backspace,Delete"toclearcells) [Na+](mEq/L) NET(mL) 0 0BODYFLUIDLOSTGastric 49.0Bile 185Pancreatic 156Smallbowel 117Diarrhea-non-osmotic 69.0Osmoticdiarrhea-sorbitol 63.0Osmoticdiarrhea-lactulose 26.0Osmoticdiarrhea-PEG 13.0Pleural/peritonealfluid/wounddrainage 137Dialysisnetultrafiltrateremoved 134Urine----enter[Na+]orestimate77mEq/LInsensiblelosses 0.0PARENTERALSOLUTIONSNetvolumegivenduringdialysis 154PackedPRBCs* 155albumin$/plasma/cryo/IVIG/platelets 130Normalsaline 154Plasma-lyteA 140Ringer'slactate 130D5W 0.0NaHCO3concentrate(50mEqper50mL) 1000100mEqNaHCO3in1LD5W 100TPN------------------------------enter[Na+]ENTERALSOLUTIONSPulmocare/Nutren2.0 57.0FibersourceHN 52.2ImpactPeptide1.5/NutrenPulmonary 50.9IsosourceHN 48.7DiabetisourceAC 46.1NovasourceRenal/Osmolyte/Jevity 41.1RepleteFiber 38.1Ensure/Nepro 36.8Peptamen 35.8Suplena 34.3VivonexRTF 30.4TwoCalHN 15.0Renalcal/Benaprotein 3.4Othersolutions-------------------enter[Na+]Othersolutions-------------------enter[Na+]

Case1•  Asurgicalpatientiseuvolemicandnormonatremic.SerumCreatinine4.5mg/dL.

•  Outputs:– Chesttubeandwounddrains:2500mL/24hours– Stool:500mL/24hours– Urineoutput:1500mL/24hours,Urine[Na+]60mEq/L

–  Insensiblelosses:~1000mL/24hours

•  Howshouldtheselossesbereplaced?

ENTRIESINYELLOWAREAS

gain/lossNS(mL)

gain/lossH2O(mL)

ONLY(aspositivevalues)(use"Space,Backspace,Delete"toclearcells)

[Na+](mEq/L)NET(mL) -3032 -2468

BODYFLUIDLOSTGastric 49.0Bile 185Pancreatic 156Smallbowel 117

Diarrhea-non-osmotic 69.0 500 -224 -276Osmoticdiarrhea-sorbitol 63.0Osmoticdiarrhea-lactulose 26.0Osmoticdiarrhea-PEG 13.0

Pleural/peritonealfluid/wounddrainage137 2500 -2224 -276Dialysisnetultrafiltrateremoved 134

Urine----enter[Na+]orestimate77mEq/L60 1500 -584 -916Insensiblelosses 0.0 1000 0 -1000PARENTERALSOLUTIONSNetvolumegivenduringdialysis 154PackedPRBCs* 155albumin$/plasma/cryo/IVIG/platelets 130Normalsaline 154Plasma-lyteA 140Ringer'slactate 130D5W 0.0NaHCO3concentrate(50mEqper50mL) 1000100mEqNaHCO3in1LD5W 100TPN------------------------------enter[Na+]ENTERALSOLUTIONSPulmocare/Nutren2.0 57.0FibersourceHN 52.2ImpactPeptide1.5/NutrenPulmonary 50.9IsosourceHN 48.7DiabetisourceAC 46.1NovasourceRenal/Osmolyte/Jevity 41.1RepleteFiber 38.1Ensure/Nepro 36.8Peptamen 35.8Suplena 34.3VivonexRTF 30.4TwoCalHN 15.0Renalcal/Benaprotein 3.4Othersolutions-------------------enter[Na+]Othersolutions-------------------enter[Na+]

Case1•  Asurgicalpatientiseuvolemicandnormonatremic.SerumCreatinine4.5mg/dL.

•  Outputs:–  Chesttubeandwounddrains:2500mL/24hours–  Stool:500mL/24hours–  Urineoutput:1500mL/24hours,Urine[Na+]60mEq/L–  Insensiblelosses:~1000mL/24hours

•  Replacementestimates:–  NSforallofchesttubeandwounddrains,½ofstooloutput,½ofurineoutput

–  D5Wfor½ofstooloutput,½ofurineoutput,PLUSinsensiblelossesof1000mL

–  Enteralandparenteralsodiumandwatercontributionshavetobeaccountedfor

NET:3000mLofNSand2500mLofwaterarerequiredtopreventhypovolemiaandhypernatremia

Case2

•  AnelderlypatientwithESRDandperipheraledemadevelopspulmonaryedemaafterHD/UF.ShehasHgof4.5g/dLandaSTEMI.

•  DuringHDshereceived1000mLofpRBCsandtolerated2000mLremovalwithUF.

Whathappened?

ENTRIESINYELLOWAREAS

gain/lossNS(mL)

gain/lossH2O(mL)

ONLY(aspositivevalues)(use"Space,Backspace,Delete"toclearcells)

[Na+](mEq/L) NET(mL) +1063 -263

BODYFLUIDLOSTGastric 49.0Bile 185Pancreatic 156Smallbowel 117Diarrhea-non-osmotic 69.0Osmoticdiarrhea-sorbitol 63.0Osmoticdiarrhea-lactulose 26.0Osmoticdiarrhea-PEG 13.0

Pleural/peritonealfluid/wounddrainage137Dialysisnetultrafiltrateremoved 134 2000 -1740 -260Urine----enter[Na+]orestimate77mEq/LInsensiblelosses 0.0PARENTERALSOLUTIONSNetvolumegivenduringdialysis 154

PackedPRBCs* 155 1000 2803 -3albumin$/plasma/cryo/IVIG/platelets 130Normalsaline 154Plasma-lyteA 140Ringer'slactate 130D5W 0.0NaHCO3concentrate(50mEqper50mL) 1000100mEqNaHCO3in1LD5W 100TPN------------------------------enter[Na+]ENTERALSOLUTIONSPulmocare/Nutren2.0 57.0FibersourceHN 52.2ImpactPeptide1.5/NutrenPulmonary 50.9IsosourceHN 48.7DiabetisourceAC 46.1NovasourceRenal/Osmolyte/Jevity 41.1RepleteFiber 38.1Ensure/Nepro 36.8Peptamen 35.8Suplena 34.3VivonexRTF 30.4TwoCalHN 15.0Renalcal/Benaprotein 3.4Othersolutions-------------------enter[Na+]Othersolutions-------------------enter[Na+]

Case2

•  AnelderlypatientwithESRDandperipheraledemadevelopspulmonaryedemaafterHD/UF.ShehasHgof4.5g/dLandaSTEMI.

•  DuringHDshereceived1000mLofpRBCsandtolerated2000mLremovalwithUF.

Whathappened?RESULT:Gainedapproximatelynet1000mLNSequivalentresultinginpulmonaryedema

Case3A58yearoldwomanwithCHFhasbeenon“fluid”restrictionandaloopdiureticfor1week.Shestillhas3+edemaofbothlegs.Herserumsodiumis155mEq/Landsheiscomplainingofthirst.Howshouldshebetreated?1)  Continuefluidrestriction2)  Givefreewater3)  GiveNSandfreewater4)  Givefreewater,restrictsodiumintakeand

continuetheloopdiuretic

Case3A58yearoldwomanwithCHFhasbeenon“fluid”restrictionandaloopdiureticfor1week.Shestillhas3+edemaofbothlegs.Herserumsodiumis155mEq/Landsheiscomplainingofthirst.Howshouldshebetreated?1)  Continuefluidrestriction2)  Givefreewater3)  GiveNSandfreewater4)  Givefreewater,restrictsodiumintakeand

continuetheloopdiuretic

Summary•  Knowledgeofsodiumconcentrationsofbodyfluidlossesandofparenteralandenteralfluidscanbeusedtooptimizevolumestatusandsodiumconcentration.

•  Specificreplacementofsodiumandwaterlossesshouldbemoreeffectiveinpreventingandtreatingimbalanceof

freewater(hyponatremia/hypernatremia)orsodium(hypovolemia/hypervolemia)

thanreplacementprotocolsbasedoncumulative“fluid”balanceortotalbodyweightchanges.

Assessment•  Totalbodywaterstatus-useserum[Na+]

-calculatefreewaterdeficitandongoing losses

•  Intravascularvolumestatus-moredifficult

ApproachtoHypernatremia•  AssessS[Na+]foreffectsofchangesinserumprotein/lipidconcentrationsandosmoles

•  Calculatefreewaterdeficitandongoinglossesandreplaceappropriately

•  AssessECFandintravascularvolumestatus–  Increased– Decreased– Euvolemic

•  Hospitalizedandcriticallyillpatientsarefrequentlynotinsteadystate.

•  Theyfrequentlyhavemismatch•  betweenbloodpressureandintravascularvolume•  betweenextravascularandintravascularvolume

•  Physicalexam,CVP,andPCWPhavelimitedsensitivityandspecificitytodetermineintravascularvolume.

•  Weneedapracticalwaytoassessintravascularvolumestatustoguidevolumetherapy.

Theproblem

Mismatchbetweenintravascularvolumeandbloodpressure(Statesinwhichbloodpressureisnotprimarilydeterminedbyintravascularvolume)

IntravascularvolumelowBloodpressurehigh

Vasoconstriction•  Stimulants(cocaine,amphetamines),

catecholamines(pheochromocytoma,severestress,deliriumtremens)

•  Severehypothyroidism

IntravascularvolumehighBloodpressurelow

Cardiacdysfunction•  Cardiogenicshock•  Severecardiomyopathy,heartfailure,valvular

heartdiseaseVasodilation•  Distributiveshock+excessvolumeresuscitation•  Autonomicneuropathy

MismatchbetweenintravascularandextravascularvolumeIntravascularvolumelowExtravascularvolumehigh

Vasodilationand/or“thirdspacing”•  Distributiveshock(sepsis,anaphylaxis)•  Hemorrhagicpancreatitis•  CrushinjuryDelayedre-equilibration•  Severerenalfailure+diuresisorultrafiltration•  Nephroticsyndrome+diuresis•  End-stageliverdisease+diuresisorlarge-volume

paracentesisorultrafiltration•  Heartfailure+diuresisorultrafiltration

IntravascularvolumehighExtravascularvolumenothigh

•  Rapidbloodtransfusion+anuriaorsevererenalfailure

•  Rapidhypertonicsodiumbicarbonateorsalineinfusion

Ultrasoundoftheinferiorvenacavacollapsibilityindexforestimationofrelativeintravascularvolume.IVCCI=(IVCmax-IVCmin)/IVCmaxx100%

•  IVCmeasured2cmfromrightatriumorathepaticvein

•  CollapsibilityIndex=(IVCmax–IVCmin)/IVCmax

AssessIntravascularVolume

Intravascularoverload

Intravasculardepletion

IVCsmall,collapsing

IVCtotalcollapse

AdvantagesofbedsideIVCUS

•  Assessmentofintravascularvolumeatthetimeofclinicalevaluationtoguidevolumeadministration,diuresisorultrafiltration

•  Multipleassessmentsofintravascularvolumeasneededaftertherapeuticinterventionsorchangeinpatientstatus

•  NodelaybetweenneedforassessmentandresultsofIVCUS

Principles for treatment of concurrent sodium and water disorders

AssessmentandManagementofHypernatremia

1)  Correctfreewaterdeficitandreplaceongoingwaterlosses

2)  Assessintravascularvolume3)  Makethepatienteuvolemicandreplace

ongoingvolumelossesREQUIRES1)  Knowledgeofinputsandoutputsthat

contributetointravascularvolumeandtotalbodywater

2)  Accurateintravascularvolumeassessment

QUESTIONS?