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6 J uly, 20106 J uly, 2010 ESIM 13, BrightonESIM 13, Brighton
The challenges ofThe challenges ofhyponatremiahyponatremia
Runolfur Palsson, MD, FACP, FASNRunolfur Palsson, MD, FACP, FASNDivisionDivision ofof NephrologyNephrology
LandspitaliLandspitali University HospitalUniversity HospitalUniversity of IcelandUniversity of Iceland
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TreatingTreating hyponatremiahyponatremia:: damneddamned ifif wewe dodo
andand damneddamned ifif wewe dondonttThomasThomas BerlBerl
HyponatremiaHyponatremia placesplaces thethe treatingtreating physicianphysician
betweenbetween aa rockrock andand aa hardhard placeplace
RichardRichard SternsSterns
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LANDSPITALI UNIVERSITY HOSPITAL DIVISION OF NEPHROLOGY
Recognize how understanding of the physiology ofRecognize how understanding of the physiology of
water homeostasis and cell volume regulation provideswater homeostasis and cell volume regulation providesa foundation for prudent treatment ofa foundation for prudent treatment ofhyponatremiahyponatremia
Be able to distinguish between acute and chronicBe able to distinguish between acute and chronichyponatremiahyponatremia
UnderstandUnderstand howhow thethe choicechoice ofoftreatmenttreatment forforhyponatremiahyponatremia dependsdepends onon severityseverity,, raterate ofofonsetonset andandthethe clinicalclinical featuresfeatures
Be able to diagnose and aggressively manage lifeBe able to diagnose and aggressively manage life--
threateningthreatening hyponatremichyponatremic emergenciesemergencies Be able to administer therapies that reliably correctBe able to administer therapies that reliably correct
hyponatremiahyponatremia at an appropriate rateat an appropriate rate
Learning objectivesLearning objectives
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LANDSPITALI UNIVERSITY HOSPITAL DIVISION OF NEPHROLOGY
Hyponatremia is defined as serum Na
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Hyponatremia is a disorderof water balance!
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LANDSPITALI UNIVERSITY HOSPITAL DIVISION OF NEPHROLOGY
Difference between intake and excretion of waterDifference between intake and excretion of waterresults in alteration of body fluid tonicityresults in alteration of body fluid tonicity
The body senses and regulates serumThe body senses and regulates serum osmolalityosmolality
(not serum Na) which is kept constant at ~285(not serum Na) which is kept constant at ~285mOsmmOsm/kg by matching water excretion and intake/kg by matching water excretion and intake
Serum Na is a surrogate marker for serumSerum Na is a surrogate marker for serum
osmolalityosmolality SerumSerum osmolalityosmolality is regulated by water balanceis regulated by water balance
(not sodium balance)(not sodium balance)
Water homeostasis: key conceptsWater homeostasis: key concepts
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OsmolalityOsmolality is equal in allis equal in allbody fluid compartmentsbody fluid compartments
SerumSerum osmolalityosmolality can becan becalculated:calculated:
OsmolalityOsmolality = 2 x serum Na += 2 x serum Na +
glucose + ureaglucose + urea EffectiveEffective osmolalityosmolality = 2 x= 2 x
serum Naserum Na
OsmolalityOsmolality of the body fluidsof the body fluids
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SumitKumar & Tomas Berl
ExcretionExcretion of fof freeree waterwater by the kidneyby the kidney
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ActionAction ofofargininearginine vasopressinvasopressin onon
thethe renalrenal principalprincipal cellcell
SumitKumar & Tomas Berl
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Increased plasma
osmolality
Decreased effectivecirculating volume
VasoconstrictionRenal water
reabsorption
Decreased plasma
osmolality
Expanded plasmavolume
AVPAVP
++
V1a receptors V2 receptors
Regulation of vasopressin secretionRegulation of vasopressin secretion
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OsmoticOsmotic andand nonosmoticnonosmotic regulationregulation
ofofvasopressinvasopressin secretionsecretion
SumitKumar & Tomas Berl
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LANDSPITALI UNIVERSITY HOSPITAL DIVISION OF NEPHROLOGY
Accumulation of water rarely occurs unless the abilityAccumulation of water rarely occurs unless the ability
to excrete water is impairedto excrete water is impaired The capacity of the kidneys to excrete water isThe capacity of the kidneys to excrete water is
normally very large or up to 15normally very large or up to 15--20 L/day20 L/day
Thus, enormous water intake is required to causeThus, enormous water intake is required to causehypotonichypotonic hyponatremiahyponatremia under normal conditionsunder normal conditions If renal water handling is impaired, then modest waterIf renal water handling is impaired, then modest water
intake can causeintake can cause hypotonicityhypotonicity Impaired water excretion leading toImpaired water excretion leading to hyponatremiahyponatremia,,
almost invariably results from the inability to suppressalmost invariably results from the inability to suppressthe secretion of vasopressinthe secretion of vasopressin
How doesHow does hyponatremiahyponatremia develop?develop?
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LANDSPITALI UNIVERSITY HOSPITAL DIVISION OF NEPHROLOGY
IsotonicIsotonic hyponatremiahyponatremia ((pseudohyponatremiapseudohyponatremia))
A laboratory artifactA laboratory artifact causedcaused byby severesevere hypertriglyceridemiahypertriglyceridemia oror
paraproteinemiaparaproteinemia thatthat isis rarelyrarely encounteredencountered todaytoday duedue totowidespreadwidespread useuse ofofionion--specificspecific electrodeelectrode forfor serumserum NaNameasurementmeasurement
HypertonicHypertonic hyponatremiahyponatremia ((translocationaltranslocational)) Caused by hyperglycemia or hypertonicCaused by hyperglycemia or hypertonic mannitolmannitol therapy resulting intherapy resulting in
osmotic shift of water from ICF to ECF, thereby diluting serum Nosmotic shift of water from ICF to ECF, thereby diluting serum Naa
Serum Na tends to decrease ~1.7Serum Na tends to decrease ~1.7 mmolmmol/L for every 5.6/L for every 5.6 mmolmmol/L (100/L (100mg/mg/dLdL) serum glucose is above its normal value) serum glucose is above its normal value
HypotonicHypotonic hyponatremiahyponatremia ((dilutionaldilutional))
By far the most common type and is caused by water retentionBy far the most common type and is caused by water retentionresulting in water excess in relation to sodium stores, which caresulting in water excess in relation to sodium stores, which cann
be decreased, normal or increasedbe decreased, normal or increased
ClassificationClassification ofofhyponatremiahyponatremia
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LANDSPITALI UNIVERSITY HOSPITAL DIVISION OF NEPHROLOGY
Impaired renal water excretionImpaired renal water excretion Decreased extracellular fluid volumeDecreased extracellular fluid volume
Increased extracellular fluid volumeIncreased extracellular fluid volume-- Heart failureHeart failure
-- CirrhosisCirrhosis
-- Advanced renal failureAdvanced renal failure
Normal extracellular fluid volumeNormal extracellular fluid volume-- ThiazideThiazide diureticsdiuretics-- Syndrome of inappropriate secretionSyndrome of inappropriate secretion
ofofantidiureticantidiuretic hormone (SIADH)hormone (SIADH)
-- Adrenal insufficiencyAdrenal insufficiency
-- HypothyroidismHypothyroidism-- Low dietary solute intakeLow dietary solute intake
Excessive water intakeExcessive water intake PsychogenicPsychogenic polydipsiapolydipsia
Associated with prolonged exerciseAssociated with prolonged exercise
CNS disorders (includingCNS disorders (includingacute psychosis)acute psychosis)
CancerCancer
MedicationsMedicationsSSRISSRIss
TricyclicTricyclicantidepressantsantidepressants
NSAIDNSAIDss
Pulmonary diseasePulmonary disease
MiscellaneousMiscellaneous Postoperative statePostoperative state
PainPain
Severe nauseaSevere nausea
Causes ofCauses ofhyponatremiahyponatremia
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LANDSPITALI UNIVERSITY HOSPITAL DIVISION OF NEPHROLOGY
Healthy individuals on a normal diet excrete 600Healthy individuals on a normal diet excrete 600--900900
mosmolesmosmoles of solute in the urine dailyof solute in the urine daily If minimum urineIf minimum urine osmolalityosmolality is 60is 60 mOsmmOsm/kg, then maximum/kg, then maximum
urine output will be 10urine output will be 10--15 L15 L
Poor dietary intake can lower the daily urinary solute excretionPoor dietary intake can lower the daily urinary solute excretionto below 250to below 250 mosmolesmosmoles, resulting in significant reduction in, resulting in significant reduction inurine volumeurine volume
Examples:Examples:
Beer drinkerBeer drinker
ss
potomaniapotomania
--
high water intake, low dietary proteinhigh water intake, low dietary protein
Tea and toastTea and toast hyponatremiahyponatremia -- a diet that is deficient in salt and proteina diet that is deficient in salt and protein
HyponatremiaHyponatremia develops if fluid intake is greater than thedevelops if fluid intake is greater than themaximum amount of urine output that can be generatedmaximum amount of urine output that can be generated
Low dietary solute intakeLow dietary solute intake
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LANDSPITALI UNIVERSITY HOSPITAL DIVISION OF NEPHROLOGY
Healthy individuals on a normal diet excrete 600Healthy individuals on a normal diet excrete 600--900900
mosmolesmosmoles of solute in the urine dailyof solute in the urine daily If minimum urineIf minimum urine osmolalityosmolality is 60is 60 mOsmmOsm/kg, then maximum/kg, then maximum
urine output will be 10urine output will be 10--15 L15 L
Poor dietary intake can lower the daily urinary solute excretionPoor dietary intake can lower the daily urinary solute excretionto below 250to below 250 mosmolesmosmoles, resulting in significant reduction in, resulting in significant reduction inurine volumeurine volume
Examples:Examples:
Beer drinkerBeer drinker
ss
potomaniapotomania
--
high water intake, low dietary proteinhigh water intake, low dietary protein
Tea and toastTea and toast hyponatremiahyponatremia -- a diet that is deficient in salt and proteina diet that is deficient in salt and protein
HyponatremiaHyponatremia develops if fluid intake is greater than thedevelops if fluid intake is greater than themaximum amount of urine output that can be generatedmaximum amount of urine output that can be generated
600600 mosmolesmosmoles 6060 mOsmmOsm/kg = 10 L/kg = 10 L
900900 mosmolesmosmoles 6060 mOsmmOsm/kg = 15 L/kg = 15 L
Low dietary solute intakeLow dietary solute intake
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Androgue & Madias, N Engl J Med 2000;342:1581-89
EffectsEffects ofofhyponatremiahyponatremia onon thethe brainbrain
andand adaptiveadaptive responsesresponses
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LANDSPITALI UNIVERSITY HOSPITAL DIVISION OF NEPHROLOGY
AcuteAcute hyponatremiahyponatremia (48 hrhr)) FrequentlyFrequently mildmild oror nono symptomssymptoms HeadacheHeadache RestlessnessRestlessness MuscleMuscle crampscramps NauseaNausea andand vomitingvomiting LethargyLethargy ConfusionConfusion andand disorientationdisorientation
Severe cerebral edemaSevere cerebral edema Risk of death fromRisk of death from
untreateduntreated hyponatremiahyponatremia
Adaptation minimizesAdaptation minimizes
brain swellingbrain swelling RiskRisk ofofinjuryinjury fromfromovertreatedovertreated hyponatremiahyponatremia
ClinicalClinical featuresfeatures ofofhyponatremiahyponatremia
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LANDSPITALI UNIVERSITY HOSPITAL DIVISION OF NEPHROLOGY
WaterWater intoxicationintoxication duedue toto compulsorycompulsoryexcessiveexcessive fluidfluid intakeintake PatientsPatients withwith severesevere psychosispsychosis
UseUse ofofecstasyecstasy (N(N--methylmethyl--3,43,4--methylenedioxyamphetamine)methylenedioxyamphetamine)
MarathonMarathon runnersrunners
Postoperative iatrogenicPostoperative iatrogenic hyponatremiahyponatremia
ClinicalClinical settingssettings ofof
acuteacute hyponatremiahyponatremia
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Normal brainHyponatremic brain edema
AcuteAcute hyponatremiahyponatremia and brain edemaand brain edema
in a marathon runnerin a marathon runner
Ayus et al, Ann IntMed 2000;132:711-14
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NoncardiogenicNoncardiogenic pulmonarypulmonary edemaedema
Ayus et al, Ann IntMed 2000;132:711-14
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LANDSPITALI UNIVERSITY HOSPITAL DIVISION OF NEPHROLOGY
A study of runners in the 2002 Boston Marathon:
488 out of 766 runners provided a blood sample at
the finish line
63 runners (13%) had hyponatremia (serumNa
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LANDSPITALI UNIVERSITY HOSPITAL DIVISION OF NEPHROLOGY
FrequentlyFrequently asymptomaticasymptomatic PatientsPatients withwith asymptomaticasymptomatic
hyponatremiahyponatremiahavehave beenbeen foundfound totohavehave aa numbernumber ofofproblemsproblems:: AttentionAttention impairmentimpairment
GaitGait instabilityinstability
FallsFalls
IncreasedIncreased riskrisk ofofbonebone fracturesfractures
ChronicChronic hyponatremiahyponatremia
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AlgorithmAlgorithm forfor thethediagnosisdiagnosis ofofhyponatremiahyponatremia
Rai et al, AmJ Nephrol 2006;26:579-89
DiagnosticDiagnostic criteriacriteria for SIADH:for SIADH:
DecreasedDecreased serumserum osmolalityosmolality(100 mOsmmOsm/kg/kg
ClinicalClinical euvolemiaeuvolemia
UrineUrine NaNa >40>40 mmolmmol/L/L withwith normalnormaldietarydietary saltsalt intakeintake
NormalNormal thyroidthyroid andand adrenaladrenalfunctionfunction
NoNo renalrenal diseasedisease NoNo recentrecent useuse ofofdiureticdiuretic agentsagents
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LANDSPITALI UNIVERSITY HOSPITAL DIVISION OF NEPHROLOGY
The rate of correction of the serum Na is determinedThe rate of correction of the serum Na is determined
by whetherby whether hyponatremiahyponatremia is acute or chronicis acute or chronic The definition of acute or chronic is largely based onThe definition of acute or chronic is largely based on
the severity of the clinical featuresthe severity of the clinical features
LifeLife--threatening acutethreatening acute hyponatremiahyponatremia requires rapidrequires rapidcorrection of serum Nacorrection of serum Na
In contrast, the treatment of chronicIn contrast, the treatment of chronic hyponatremiahyponatremia
should be cautious because too rapid correction ofshould be cautious because too rapid correction ofthe serum Na can result in dangerous osmoticthe serum Na can result in dangerous osmoticdemyelinationdemyelination injury of the brainsteminjury of the brainstem
Treatment ofTreatment ofhyponatremiahyponatremia
can be a dilemma!can be a dilemma!
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OsmoticOsmotic demyelinationdemyelination syndromesyndrome
Demyelination lesion
Sveinsson et al, Icelandic Med J 2008;94:665-71
Normal brain Central pontine myelinolysis
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LANDSPITALI UNIVERSITY HOSPITAL DIVISION OF NEPHROLOGY
Rapid elevation of the serum Na is necessary, particularlyRapid elevation of the serum Na is necessary, particularlyif the clinical manifestations are severeif the clinical manifestations are severe
RaisingRaising thethe serumserum NaNa 44--66 mmolmmol/L/L overover 22--33 hourshours appearsappears
enoughenough
toto
preventprevent
seriousserious
neurologicneurologic
complicationscomplications
Administer 3%Administer 3% NaClNaCl (513(513 mmolmmol/L), 1/L), 1--2 ml/kg IV per hour2 ml/kg IV per hour
Should elevate theShould elevate the serumserum NaNa approximately 1approximately 1--22 mmolmmol/L/Lper hourper hour
Subsequently, the rate of correction should be less than 10Subsequently, the rate of correction should be less than 10mmolmmol/L per 24 hours/L per 24 hours
Treatment of acuteTreatment of acute hyponatremichyponatremic
encephalopathyencephalopathy
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Androgue-Madias formula:
Change in serum Na = infusate Na serum Natotal body water + 1
Estimates the effect of 1 liter of any fluid infused on serum Na Assumes all of the infusate is retained; does not consider urine
losses of electrolyte or water
Adrogu et al. N Engl J Med. 2000;342:1581-89
HowHow muchmuch hypertonichypertonic salinesaline
shouldshould bebe administeredadministered??
Ch i h i
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LANDSPITALI UNIVERSITY HOSPITAL DIVISION OF NEPHROLOGY
ClinicalClinical observationsobservations suggestsuggest thatthat thethe riskrisk ofofdemyelinationdemyelination injuryinjury of the brain is increased ifof the brain is increased ifthethe raterate ofofcorrectioncorrection ofofthethe serumserum NaNa is fasteris faster
thanthan 1212 mmolmmol/L/L inin thethe firstfirst 2424 hourshours andand 1818mmolmmol/L/L inin 4848 hourshours
ThisThis isis particularlyparticularly importantimportant inin patientspatients withwith
extremeextreme hyponatremiahyponatremia ((serumserum NaNa
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LANDSPITALI UNIVERSITY HOSPITAL DIVISION OF NEPHROLOGY
GoalsGoals
::
66--88 mmolmmol/L/L inin 2424 hourshours
1212--1414 mmolmmol/L/L inin 4848 hourshours
1414--1616 mmolmmol/L/L inin 7272 hourshours LimitsLimits::
LessLess thanthan 1010 mmolmmol/L/L inin 2424 hourshours
LessLess thanthan 1818 mmolmmol/L/L inin 4848 hourshours LessLess thanthan 2020 mmolmmol/L/L inin 7272 hourshours
SternsSterns
et al,et al,
SeminSemin
NephrolNephrol
2009;29:2822009;29:282
--9999
TreatmentTreatment ofofchronicchronic hyponatremiahyponatremia::
recommendedrecommended ratesrates ofofcorrectioncorrection
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LANDSPITALI UNIVERSITY HOSPITAL DIVISION OF NEPHROLOGY
EffectiveEffective inin correctingcorrecting hyponatremiahyponatremia causedcaused byby
volumevolume depletiondepletion Eliminates volume stimulus for vasopressin secretionEliminates volume stimulus for vasopressin secretion
Unpredictable onset of waterUnpredictable onset of water diuresisdiuresis
InIn SIADH,SIADH, isotonicisotonic salinesaline isis ineffectiveineffective andand maymay lowerlowerthe serum sodiumthe serum sodium
IfIfthethe sodiumsodium containedcontained inin aa literliter ofofsalinesaline isis excretedexcretedinin lessless thanthan aa literliter ofofurineurine;; thethe netnet effecteffect isis freefree waterwater
retentionretention ThusThus,, wewe reservereserve isotonicisotonic salinesaline forfor hyponatremichyponatremic
patientspatients whowho requirerequire treatmenttreatment forfor volumevolume depletiondepletion
IsotonicIsotonic salinesaline
T t tT t t ff t i dt i d l il i
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LANDSPITALI UNIVERSITY HOSPITAL DIVISION OF NEPHROLOGY
ConventionalConventional treatmenttreatment optionsoptions areare suboptimalsuboptimal
becausebecause ofoflimitedlimited efficacyefficacy andand poorpoor safetysafety andandtolerabilitytolerability IdentifyIdentify andand treattreat thethe underlyingunderlying causecause FluidFluid restrictionrestriction 0.50.5--1.0 L/1.0 L/dayday isis thethe mainstaymainstay butbut
poorlypoorly toleratedtolerated longlong--termterm DrugDrug therapiestherapies::
LoopLoop diureticsdiuretics plusplus increasedincreased saltsalt intakeintake
DemeclocyclineDemeclocycline 600600--1200 mg/1200 mg/dayday LithiumLithium 600600--900 mg/900 mg/dayday UreaUrea 30 g/30 g/dayday VasopressorVasopressor receptorreceptor antagonistsantagonists
TreatmentTreatment ofofsustainedsustained euvolemiceuvolemic
andand hypervolemichypervolemic hyponatremiahyponatremia
Wh tWh t l ll l ff fl idfl id t i tit i ti
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LANDSPITALI UNIVERSITY HOSPITAL DIVISION OF NEPHROLOGY
UNa + UKUNa + UK FluidFluid restrictionrestrictionSNaSNa
>1>1
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SchrierSchrier et al, Net al, N EnglEnglJJ MedMed 2006;355:20992006;355:2099--122122
Treatment hyponatremia with tolvaptan
Randomized controlled trial
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LANDSPITALI UNIVERSITY HOSPITAL DIVISION OF NEPHROLOGY
WhenWhen aa reversiblereversible causecause ofofwaterwater retentionretention isis correctedcorrected,,
vasopressinvasopressin levelslevels fallfall andand thethe excretionexcretion ofofdilutedilute urineurine causescausesserumserum NaNa toto riserise rapidlyrapidly
Maximally dilute urine increases the serum Na by >2Maximally dilute urine increases the serum Na by >2 mmolmmol/L/hr/L/hr
CanCan occuroccur whenwhen excessiveexcessive waterwater drinkingdrinking isis discontinueddiscontinued oror
impairedimpaired renalrenal waterwater excretionexcretion isis correctedcorrected Continued vigilance is essential:Continued vigilance is essential:
Monitor urine output and measure serum Na frequentlyMonitor urine output and measure serum Na frequently
IfIfurineurine outputoutput suddenlysuddenly increasesincreases,, thenthen oneone shouldshould attemptattempt totocounteractcounteract thethe elevationelevation ofofserumserum NaNa AdministerAdminister 5%5% dextrosedextrose IVIV
AdministerAdminister desmopressdesmopressnn (DDAVP)(DDAVP) parenterallyparenterally
OvercorrectionOvercorrection ofofserumserum sodiumsodium
R lRe ersal fof i d t tinad ertent tio ercorrection
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PerianayagamPerianayagamet al,et al, ClinClinJJ AmAmSocSoc NephrolNephrol 2008;3:3312008;3:331--66
ReversalReversal ofofinadvertentinadvertent overcorrectionovercorrection
ofofhyponatremiahyponatremia
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LANDSPITALI UNIVERSITY HOSPITAL DIVISION OF NEPHROLOGY
A 67 year old female was brought to the emergencydepartment following a seizure that occurred in the setting of
progressive weakness for several days There was a history of recently diagnosed small cell lung
cancer
On physical exam she was lethargic and confused;
Wt 60 kg, BP 125/75 without orthostatic drop, P 90; lungswere clear and there was no edema
Laboratory studies Blood: Na 112 mmol/L, K 4.2 mmol/L, Cl 76 mmol/L, CO2 26
mmol/L, creatinine 80 mol/L (0.9 mg/dL), osmolality 234 mOsm/kg
Urine: Osmolality 660 mOsm/kg, Na 102 mmol/L, K 64 mmol/L
CT scan of the brain showed evidence for mild cerebraledema but no other abnormalities
Case PresentationCase Presentation
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LANDSPITALI UNIVERSITY HOSPITAL DIVISION OF NEPHROLOGY
How do you judge the volume status of the patient?
Euvolemic
What is a likely cause of the hyponatremia?
SIADH due to ectopic production of vasopressin by the lung
cancer
Is the hyponatremia acute or chronic?
Serious neurological signs and symptoms indicate acute
hyponatremia with brain edema Duration unknown, but probably a significant chronic
component
DiagnosisDiagnosis
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LANDSPITALI UNIVERSITY HOSPITAL DIVISION OF NEPHROLOGY
How should this patient be treated?
Hypertonic saline with close monitoring The goal is to raise the serum Na by ~5-6 mmol/L over 2-3
hours
How much hypertonic (3%) saline should be
administered? Concurrent furosemide therapy may be required to
increase free water clearance
Closely monitor the patients clinical status, urineoutput and and measure serum Na every 1-2 hours
Immediate managementImmediate management
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LANDSPITALI UNIVERSITY HOSPITAL DIVISION OF NEPHROLOGY
How should this patient be treated?
Hypertonic saline with close monitoring The goal is to raise the serum Na by ~5-6 mmol/L over 2-3
hours
How much hypertonic (3%) saline should be
administered? Concurrent furosemide therapy may be required to
increase free water clearance
Closely monitor the patients clinical status, urineoutput and and measure serum Na every 1-2 hours
Androgue-Madias formula:Change in serum Na = infusate Na serum Na total body water + 1Change in serum Na = 513 mmol 112 mmol/L 30 L + 1 = 12.9 mmol/LThus, 1 L of 3% saline will increase the serum Na by 12.9 mmol/L
6 12.9 = 0.465 L => 155 mL per hour will be needed
Immediate managementImmediate management
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LANDSPITALI UNIVERSITY HOSPITAL DIVISION OF NEPHROLOGY
Fluid restriction
How much? To get any meaningful improvement in serum Na,
would need to completely eliminate all p.o. or i.v.
electrolyte-free H2O Additional strategies:
Increase daily solute load (salt tablets, urea)
Furosemide
Tolvaptan
The patient needs continued close monitoring
LongLong--term managementterm management
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LANDSPITALI UNIVERSITY HOSPITAL DIVISION OF NEPHROLOGY
Fluid restriction
How much? To get any meaningful improvement in serum Na,
would need to completely eliminate all p.o. or i.v.
electrolyte-free H2O Additional strategies:
Increase daily solute load (salt tablets, urea)
Furosemide
Tolvaptan
The patient needs continued close monitoring
Estimation of electrolyte-free water excretion:Urine Na + Kserum Na166 112 = 1.4
>1 indicates that no free-water excretion is occurring
LongLong--term managementterm management
Th kThank ou ffor our tt tiattention!!
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ThankThank youyou forfor youryour attentionattention!!