Electrolytes Disorders
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Transcript of Electrolytes Disorders
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
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ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Composition of body fluidsComposition of body fluids Fluid CompartmentsFluid Compartments Fluid balanceFluid balance Specific ElectrolytesSpecific Electrolytes
– SodiumSodium– PotassiumPotassium– MagnesiumMagnesium– CalciumCalcium– PhosphorusPhosphorus
Key pointsKey points QuestionsQuestions
Outline
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Total fluid volume 42 litersECF 33% --- 1) Plasma 7% 2) Interstitial Fluid 26% 3) Lymph <1%ICF 67% mEqui per liter
Cations Plasma ISF Cell
Na+ 142.0 145.1 12
K+ 4.3 4.4 150
Ca2+ 5 2.4 4
Mg2+ 3 1.5 34
Total 154 153.0 200
Anions Plasma ISF Cell
Cl- 104 117.4 4
HCO3- 24 27.1 12
Phosphates 2 2.3 40
Proteins 14 0.0 54
Other 5.9 6.2 90
Total 149.9 153.0 200
Body Fluid Composition
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Fluid Compartments
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Serum OsmolalitySerum Osmolality– Number of osmoles (osmotically Number of osmoles (osmotically
active particles) in the serumactive particles) in the serum– Normal rangeNormal range
275 to 295 mosm/L275 to 295 mosm/L
Fluid Balance
2[Serum Na+] + ------------ + ------------Glucose BUN
18 2.8
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Major extracellular cationMajor extracellular cation Normal rangeNormal range
– 135 to 150 meq/L135 to 150 meq/L
Sodium
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Serum NaSerum Na++ < 135 meq/L < 135 meq/L– Primary water gain or NaPrimary water gain or Na++ loss > water loss > water– Altered distribution of body waterAltered distribution of body water– Sx’s related to rate of change > NaSx’s related to rate of change > Na++
valuevalue– Sx at NaSx at Na++ < 120 meq/L < 120 meq/L– Seizures likely at NaSeizures likely at Na++ << 113 113
Hyponatremia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Pathophysiology: CNSPathophysiology: CNS– Water shifts into brain cellsWater shifts into brain cells
– ApathyApathy –– Altered Altered ConsciousnessConsciousness
– AgitationAgitation –– Seizures Seizures– HeadacheHeadache –– Coma Coma
– Risk of brain damage > during Risk of brain damage > during treatmenttreatment
– Central Pontine Myelinolysis (CPM)Central Pontine Myelinolysis (CPM)
Hyponatremia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Pathophysiology: CardiovascularPathophysiology: Cardiovascular– Effect depends on arterial blood Effect depends on arterial blood
volumevolume– Volume depletionVolume depletion
Water shifts from ECF ICFWater shifts from ECF ICF Shock at lesser degrees of TBW depletionShock at lesser degrees of TBW depletion
– ADH Opposes effects of fluid shiftsADH Opposes effects of fluid shifts Increases water reabsorption ?????Increases water reabsorption ????? Potent vasoconstrictorPotent vasoconstrictor
Hyponatremia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Pathophysiology: Musculoskeletal Pathophysiology: Musculoskeletal SystemSystem– Muscle cramps & weakness with Muscle cramps & weakness with
exerciseexercise– Sx if sweat losses replaced with Sx if sweat losses replaced with
waterwater
Hyponatremia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Pathophysiology: Renal SystemPathophysiology: Renal System– Production of dilute urineProduction of dilute urine– Impacted by amount of ADH presentImpacted by amount of ADH present– Urine NaUrine Na++ < 10 renal handling of < 10 renal handling of
NA intactNA intact– Urine NaUrine Na++ > 20 intrinsic renal > 20 intrinsic renal
tubular damagetubular damage
Hyponatremia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
DiagnosisDiagnosis
Hyponatremia
Plasma Osmolality
Normal (275-295)Isotonichyponatremia
Low (< 275)Hypotonichyponatremia
High (> 295)Hypertonichyponatremia
Hypovolemic Hypervolemic Euvolemic
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
HypertonicHypertonic Hyponatremia (P Hyponatremia (Posmosm > > 295)295)– Large quantities of solute in ECFLarge quantities of solute in ECF– Water moves from ICF ECFWater moves from ICF ECF– Hyperglycemia most common causeHyperglycemia most common cause
Each 100 mg/dl plasma glucose will Each 100 mg/dl plasma glucose will serum Naserum Na++ by 1.6 meq/L by 1.6 meq/L
– TreatmentTreatment Volume replacementVolume replacement
Hyponatremia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
IsotonicIsotonic Hyponatremia (P Hyponatremia (Posmosm 275 - 275 - 295)295)– ““Pseudohyponatremia”Pseudohyponatremia”– Artifact in serum NaArtifact in serum Na++ measurement measurement
22° High levels of plasma proteins and ° High levels of plasma proteins and lipidslipids
– Etiology:Etiology: HyperlipidemiaHyperlipidemia HyperproteinemiaHyperproteinemia
Hyponatremia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
HypotonicHypotonic Hyponatremia (P Hyponatremia (Posmosm < < 275)275)
Hyponatremia
Plasma Osmolality
Normal (275-295)Isotonichyponatremia
Low (< 275)Hypotonichyponatremia
High (> 295)Hypertonichyponatremia
Hypovolemic Hypervolemic Euvolemic
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
HypotonicHypotonic Hyponatremia Hyponatremia– Hypovolemic vs Hypervolemic vs Hypovolemic vs Hypervolemic vs
EuvolemicEuvolemic Plasma electrolytes and osmolalityPlasma electrolytes and osmolality Urine electrolytes and osmolalityUrine electrolytes and osmolality
Hyponatremia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
HypovolemicHypovolemic Hyponatremia Hyponatremia– Loss of NaLoss of Na++ and water and water– Replacement with hypotonic fluidsReplacement with hypotonic fluids– Sodium loss “renal” vs “extrarenal”Sodium loss “renal” vs “extrarenal”
Hyponatremia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
HypovolemicHypovolemic Hyponatremia Hyponatremia– Renal NaRenal Na++ loss loss
Urine NaUrine Na++ > 20 meq/L > 20 meq/L Etiology:Etiology:
– Diuretic useDiuretic use– Salt-wasting nephropathy (renal tubular acidosis, Salt-wasting nephropathy (renal tubular acidosis,
chronic renal failure, interstitial nephritis)chronic renal failure, interstitial nephritis)– Osmotic diuresis (glucose, urea, mannitol, Osmotic diuresis (glucose, urea, mannitol,
hyperproteinemiahyperproteinemia– Mineralocorticoid (aldosterone) deficiencyMineralocorticoid (aldosterone) deficiency
Hyponatremia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
HypovolemicHypovolemic Hyponatremia Hyponatremia– Extrarenal NaExtrarenal Na++ loss loss
Urine NaUrine Na++ < 20 meq/L < 20 meq/L Etiology:Etiology:
– Volume replacement with hypotonic fluidsVolume replacement with hypotonic fluids– GI loss (vomiting, diarrhea, fistula, tube suction)GI loss (vomiting, diarrhea, fistula, tube suction)– Third-space loss (burns, hemorrhagic pancreatitis, Third-space loss (burns, hemorrhagic pancreatitis,
peritonitis)peritonitis)– Sweating (cystic fibrosis)Sweating (cystic fibrosis)
Hyponatremia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
HypovolemicHypovolemic Hyponatremia Hyponatremia– TreatmentTreatment
Re-expansion of ECF with isotonic salineRe-expansion of ECF with isotonic saline Correction of underlying disorderCorrection of underlying disorder
Hyponatremia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
EuvolemicEuvolemic Hyponatremia Hyponatremia– Normal volume status and Normal volume status and
hyponatremiahyponatremia– Sx usually 2Sx usually 2° CNS hypotonicity° CNS hypotonicity– Urine NaUrine Na++ > 20 meq/L > 20 meq/L– SIADH most notable causeSIADH most notable cause
Hyponatremia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
EuvolemicEuvolemic Hyponatremia Hyponatremia– SIADHSIADH
Hypotonic hyponatremiaHypotonic hyponatremia Inappropriately elevated urine osmolality (usually > Inappropriately elevated urine osmolality (usually >
200 mosm/kg)200 mosm/kg) Elevated urine NaElevated urine Na++ (> 20 meq/L) (> 20 meq/L) Clinical euvolemiaClinical euvolemia Normal adrenal, renal, cardiac, hepatic, and thyroid Normal adrenal, renal, cardiac, hepatic, and thyroid
functionfunction Correctable with water restrictionCorrectable with water restriction
Hyponatremia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
EuvolemicEuvolemic Hyponatremia Hyponatremia– Etiology:Etiology:
HypothyroidismHypothyroidism Pain, stress, nausea, psychosis (stimulates Pain, stress, nausea, psychosis (stimulates
ADH)ADH) Drugs: ADH, nicotine, sulfonylureas, Drugs: ADH, nicotine, sulfonylureas,
morphine, barbs, NSAIDS, APAP, morphine, barbs, NSAIDS, APAP, Carbamazepine, Phenothiazines, TCAs, Carbamazepine, Phenothiazines, TCAs, Colchicine, Clofibrate, Cyclophosphamide, Colchicine, Clofibrate, Cyclophosphamide, Isoproterenol, Tolbutamide, MAOIsIsoproterenol, Tolbutamide, MAOIs
Hyponatremia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
EuvolemicEuvolemic Hyponatremia Hyponatremia– Etiology (Cont):Etiology (Cont):
Water intoxication (psychogenic polydipsia)Water intoxication (psychogenic polydipsia) Glucocorticoid deficiencyGlucocorticoid deficiency Positive pressure ventilationPositive pressure ventilation PorphyriaPorphyria Essential (reset osmostat or sick cell Essential (reset osmostat or sick cell
syndrome)syndrome)
Hyponatremia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
EuvolemicEuvolemic Hyponatremia Hyponatremia– TreatmentTreatment
Fluid restrictionFluid restriction Work-up and management of underlying Work-up and management of underlying
disorderdisorder Hospital admission usually warrantedHospital admission usually warranted
Hyponatremia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
HypervolemicHypervolemic Hyponatremia Hyponatremia– Total body water in great excessTotal body water in great excess– Sx of volume overloadSx of volume overload
Peripheral/pulmonary edemaPeripheral/pulmonary edema
– Impaired water excretionImpaired water excretion– Water retention in excess of NaWater retention in excess of Na++
retentionretention
Hyponatremia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
HypervolemicHypervolemic Hyponatremia Hyponatremia– Without advanced renal insufficiencyWithout advanced renal insufficiency
Urine NaUrine Na++ < 20 meq/L < 20 meq/L Cirrhosis, ascites, CHF, Nephrotic syndromeCirrhosis, ascites, CHF, Nephrotic syndrome
– Advanced acute or chronic renal Advanced acute or chronic renal insufficiencyinsufficiency Urine NaUrine Na++ > 20 meq/L > 20 meq/L Renal failure (inability to excrete free Renal failure (inability to excrete free
water)water)
Hyponatremia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
HypervolemicHypervolemic Hyponatremia Hyponatremia– TreatmentTreatment
Optimize treatment for underlying disorderOptimize treatment for underlying disorder Judicious salt and water restrictionJudicious salt and water restriction ++ Diuretics Diuretics ++ Dialysis Dialysis
Hyponatremia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Treatment of Severe HyponatremiaTreatment of Severe Hyponatremia– Indications:Indications:
Serum NaSerum Na++ < 120 meq/L < 120 meq/L Rapid development ( NaRapid development ( Na++ > 0.5 meq/L/hr) > 0.5 meq/L/hr) Patient in extremis (coma, seizures)Patient in extremis (coma, seizures)
– 3% Saline Solution (513 meq/L) @ 25 - 3% Saline Solution (513 meq/L) @ 25 - 100 ml/hr100 ml/hr NaNa++ should not exceed 0.5 – 1.0 meq/L/hr should not exceed 0.5 – 1.0 meq/L/hr
Hyponatremia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Complications of TherapyComplications of Therapy– Central Pontine Myelinolysis (CPM)Central Pontine Myelinolysis (CPM)
22° excessively rapid correction of ° excessively rapid correction of hyponatremiahyponatremia
Fluctuating level of consciousnessFluctuating level of consciousness Behavioral disturbancesBehavioral disturbances DysarthriaDysarthria DysphagiaDysphagia ConvulsionsConvulsions Pseudobulbar palsyPseudobulbar palsy QuadriparesisQuadriparesis
Hyponatremia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Serum NaSerum Na++ > 150 meq/L > 150 meq/L– DDecrease in total body waterecrease in total body water
Reduced intakeReduced intake Excessive lossExcessive loss
– Thirst is body’s defensive mechanismThirst is body’s defensive mechanism
Hypernatremia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
PathophysiologyPathophysiology– 2 Primary Mechanisms2 Primary Mechanisms
Renal response to ADHRenal response to ADH– Conservation of free waterConservation of free water– Urine output with osmolality > 1000 mosm/kgUrine output with osmolality > 1000 mosm/kg
Failure of ADH responseFailure of ADH response– Inability to excrete NaInability to excrete Na++ properly properly– Urine osmolality 200-300 mosm/kgUrine osmolality 200-300 mosm/kg– Urinary NaUrinary Na++ 60-100 meq/kg 60-100 meq/kg
Hypernatremia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
PathophysiologyPathophysiology– Rapid hypertonicity or short durationRapid hypertonicity or short duration
Loss of 10% of body wt 2° dehydrationLoss of 10% of body wt 2° dehydration– Skin turgor, “doughy” skinSkin turgor, “doughy” skin
CNS cellular dehydrationCNS cellular dehydration– HemorrhageHemorrhage– Tearing of cerebral blood vessels 2° brain shrinkageTearing of cerebral blood vessels 2° brain shrinkage
– Gradual hypertonicityGradual hypertonicity Idiogenic osmoles prevent brain shrinkageIdiogenic osmoles prevent brain shrinkage
Hypernatremia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
EtiologyEtiology– Excessive sodium intakeExcessive sodium intake
Iatrogenic NaIatrogenic Na++ administration administration Seawater ingestionSeawater ingestion Mineralocorticoid or glucocorticoid excessMineralocorticoid or glucocorticoid excess
– Pure water lossPure water loss Inability to swallow, bedridden, comatoseInability to swallow, bedridden, comatose
Hypernatremia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Etiology (Cont):Etiology (Cont):– Loss of water in excess of NaLoss of water in excess of Na++
GastrointestinalGastrointestinal– Vomiting, diarrheaVomiting, diarrhea
RenalRenal– Central Diabetes InsipidusCentral Diabetes Insipidus– Impaired renal concentrating abilityImpaired renal concentrating ability
DrugsDrugs– Alcohol, Lithium, Phenytoin, Propoxyphene, Alcohol, Lithium, Phenytoin, Propoxyphene,
SulfonylureasSulfonylureas
Hypernatremia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Etiology (Cont):Etiology (Cont):– Loss of water in excess of NaLoss of water in excess of Na++
Skin lossSkin loss– Burns, sweatingBurns, sweating
Peritoneal dialysisPeritoneal dialysis
Hypernatremia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Clinical Features:Clinical Features:– Acute sx at NaAcute sx at Na++ > 158 meq/L > 158 meq/L
OsmolOsmol– Restless, irritabilityRestless, irritability 350-375350-375– Tremulousness, ataxiaTremulousness, ataxia 375-375-
400400– Hyperreflexia, twitching, spasticityHyperreflexia, twitching, spasticity 400-400-
430430– Seizures and deathSeizures and death > 430> 430
Hypernatremia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
TreatmentTreatment– **Volume replacement****Volume replacement**
NS/LR until tissue perfusion restoredNS/LR until tissue perfusion restored 0.45% Saline until urine output 0.45% Saline until urine output >>
0.5mL/kg/hr0.5mL/kg/hr
– in Nain Na++ should not exceed 10-15 should not exceed 10-15 meq/L/daymeq/L/day Monitor serum electrolytes frequentlyMonitor serum electrolytes frequently
– Manage underlying disorderManage underlying disorder
Hypernatremia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Complications of therapyComplications of therapy– Excessively rapid correctionExcessively rapid correction
Cerebral edemaCerebral edema SeizuresSeizures Permanent neuro sequelaePermanent neuro sequelae DeathDeath
Hypernatremia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Major intracellular cationMajor intracellular cation Normal rangeNormal range
– 3.5 to 5.5 meq/L3.5 to 5.5 meq/L Serum level does not reflect total Serum level does not reflect total
body Kbody K++
Potassium
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Serum KSerum K++ < 3.5 meq/L < 3.5 meq/L PathophysiologyPathophysiology
– KK++ shifts into cells as ECF pH rises shifts into cells as ECF pH rises 0.10 in pH causes 0.5 meq/l in serum K0.10 in pH causes 0.5 meq/l in serum K++
– KK++ losses usually via GI tract or kidneys losses usually via GI tract or kidneys– Aldosterone 2Aldosterone 2° volume loss° volume loss
NaNa++ & HCO & HCO33-- retention in exchange for K retention in exchange for K++
Hypokalemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
EtiologyEtiology– ECF ICF shiftsECF ICF shifts
Metabolic alkalosisMetabolic alkalosis Trtm of DKA (increased insulin)Trtm of DKA (increased insulin)
– Decreased intakeDecreased intake– GI lossGI loss
Vomiting, diarrhea, malabsorptionVomiting, diarrhea, malabsorption
Hypokalemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Etiology (Cont)Etiology (Cont)– Renal lossRenal loss
Diuretics, AldosteronismDiuretics, Aldosteronism Osmotic diuresisOsmotic diuresis Licorice, chewing tobaccoLicorice, chewing tobacco
– Drugs/ToxinsDrugs/Toxins PCN, Amphotericin B, Lithium, Thalium, PCN, Amphotericin B, Lithium, Thalium,
DopamineDopamine
– Sweat lossSweat loss
Hypokalemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Clinical FeaturesClinical Features– Sx onset at serum KSx onset at serum K++ << 2.5 meq/L 2.5 meq/L– CardiovascularCardiovascular
Increased HTNIncreased HTN Orthostatic hypotensionOrthostatic hypotension DysrhythmiasDysrhythmias EKG abnormalitiesEKG abnormalities
– Flat T-waves, prominent U-waves, ST-segment Flat T-waves, prominent U-waves, ST-segment depressiondepression
Hypokalemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Clinical Features (Cont):Clinical Features (Cont):– NeuromuscularNeuromuscular
Malaise, weakness, fatigueMalaise, weakness, fatigue Hyporeflexia, cramps, paresthesiasHyporeflexia, cramps, paresthesias
– RenalRenal Increased ammonia production Increased ammonia production
encephalopathyencephalopathy Decreased GFRDecreased GFR
– GastrointestinalGastrointestinal IleusIleus
Hypokalemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
TreatmentTreatment– Replace KReplace K++
OralOral IntravenousIntravenous
– 10-20 meq/L in 100 mL NS10-20 meq/L in 100 mL NS– Not > 40 meq in a single liter IV fluidNot > 40 meq in a single liter IV fluid– Not > 40 meq in 1 hourNot > 40 meq in 1 hour– Concentrations > 20 meq/L require a central lineConcentrations > 20 meq/L require a central line
20 meq will serum K20 meq will serum K++ ≈ 0.25 meq/L ≈ 0.25 meq/L
– Cardiac monitor during replacement Cardiac monitor during replacement therapytherapy
Hypokalemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Serum KSerum K++ > 5.5 meq/L > 5.5 meq/L– Oliguric renal failureOliguric renal failure– Severe hemolysisSevere hemolysis– Excessive tissue breakdownExcessive tissue breakdown
PseudohyperkalemiaPseudohyperkalemia– Hemolysis during blood drawHemolysis during blood draw– Cell breakdown after 30 minutesCell breakdown after 30 minutes
Hyperkalemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
EtiologyEtiology– ICF ECF shiftsICF ECF shifts
AcidosisAcidosis Beta blockadeBeta blockade Insulin deficiencyInsulin deficiency Digitalis intoxicationDigitalis intoxication
– KK++ load load Supplements, foods, KSupplements, foods, K++ containing drugs containing drugs Blood transfusionBlood transfusion RhabdomyolysisRhabdomyolysis
Hyperkalemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Etiology (Cont)Etiology (Cont)– Decreased excretionDecreased excretion
Renal failureRenal failure DrugsDrugs
– KK++ sparing diuretics, B-Blockers, NSAIDs, ACE sparing diuretics, B-Blockers, NSAIDs, ACE InhibitorsInhibitors
Aldosterone deficiencyAldosterone deficiency
Hyperkalemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Clinical FeaturesClinical Features– CardiovascularCardiovascular
V-Fib, complete heart block, asystoleV-Fib, complete heart block, asystole EKG abnormalitiesEKG abnormalities
– Tall, peaked T-waves, short QT, prolonged PRTall, peaked T-waves, short QT, prolonged PR– QRS widening, flattening of P-waveQRS widening, flattening of P-wave– QRS complex degrades into sine wave patternQRS complex degrades into sine wave pattern
Hyperkalemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
EKGEKG
Hyperkalemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Clinical Features (Cont)Clinical Features (Cont)– NeuromuscularNeuromuscular
Weakness, paresthesiasWeakness, paresthesias Areflexia, ascending paralysisAreflexia, ascending paralysis
– GastrointestinalGastrointestinal N/V, intestinal colicN/V, intestinal colic DiarrheaDiarrhea
Hyperkalemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
TreatmentTreatment– Membrane stabilizationMembrane stabilization
Cardiac irritability or KCardiac irritability or K++ > 7.5 meq/L > 7.5 meq/L 10% Calcium Gluconate or Calcium Chloride10% Calcium Gluconate or Calcium Chloride
– Redistribution (Shift KRedistribution (Shift K++ to the ICF) to the ICF) Glucose/Insulin (bolus, infusion)Glucose/Insulin (bolus, infusion) NaHCONaHCO33 - 50 to 100 meq IV over 2 min - 50 to 100 meq IV over 2 min B-Agonists (Albuterol neb)B-Agonists (Albuterol neb)
Hyperkalemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
TreatmentTreatment– Remove KRemove K++ from the body from the body
DiureticsDiuretics– Lasix 40 mg IVLasix 40 mg IV
Kaexalate PO/PRKaexalate PO/PR– Each gram eliminates 1 meq KEach gram eliminates 1 meq K++
DialysisDialysis– Severely ill or already on dialysis Severely ill or already on dialysis
Hyperkalemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Normal rangeNormal range– 8.5 to 10.5 mg/dL8.5 to 10.5 mg/dL– Ionized fraction is physiologically Ionized fraction is physiologically
activeactive
Calcium
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
HypocalcemiaHypocalcemia– Serum CaSerum Ca2+2+ < 8.5 mg/dL < 8.5 mg/dL– Ionized level < 2.0 meq/LIonized level < 2.0 meq/L– Common CausesCommon Causes
ShockShock SepsisSepsis Renal failureRenal failure PancreatitisPancreatitis
Hypocalcemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
EtiologyEtiology– HypoalbuminemiaHypoalbuminemia– Vitamin D deficiencyVitamin D deficiency
HypoparathyroidismHypoparathyroidism HyperphosphatemiaHyperphosphatemia MalignancyMalignancy
– DrugsDrugs Cimetidine, Phosphates, Dilantin, Phenobarbital,
Glucagon, Aminoglycosides, Cisplatin, Heparin, Theophylline, Protamine, Norepinephrine, Loop diuretics, Glucocorticoids, Magnesium Sulfate, Nitroprusside
Hypocalcemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Clinical FeaturesClinical Features– NeurologicalNeurological
Circumoral & digital paresthesiasCircumoral & digital paresthesias TetanyTetany Chvostek signChvostek sign Trousseau signTrousseau sign Impaired memory, confusionImpaired memory, confusion Hallucinations, dementia, seizuresHallucinations, dementia, seizures
Hypocalcemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Clinical Features (Cont)Clinical Features (Cont)– MuscularMuscular
Spasms, cramps, weaknessSpasms, cramps, weakness
– DermatologicDermatologic HyperpigmentationHyperpigmentation Coarse, brittle hairCoarse, brittle hair Dry, scaly skinDry, scaly skin
Hypocalcemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Clinical Features (Cont)Clinical Features (Cont)– CardiovascularCardiovascular
Heart failureHeart failure VasoconstrictionVasoconstriction EKG abnormalitiesEKG abnormalities
– Prolonged QTProlonged QT
– SkeletalSkeletal OsteodystrophyOsteodystrophy RicketsRickets OsteomalaciaOsteomalacia
Hypocalcemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Clinical Features (Cont)Clinical Features (Cont)– Skeletal (Cont)Skeletal (Cont)
X-Ray abnormalitiesX-Ray abnormalities– CraniotabesCraniotabes– Frontal skull bossingFrontal skull bossing– Rachitic rosary ribsRachitic rosary ribs– Widened rib cageWidened rib cage– Bowed legsBowed legs– Bone demineralizationBone demineralization
Hypocalcemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
TreatmentTreatment– AsymptomaticAsymptomatic
Oral replacementOral replacement
– Symptomatic or SevereSymptomatic or Severe 10% Calcium Gluconate IV, 10-30 ml10% Calcium Gluconate IV, 10-30 ml 10% Calcium Chloride IV, 10 ml10% Calcium Chloride IV, 10 ml
Hypocalcemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Total CaTotal Ca2+2+ > 10.5 mg/dL > 10.5 mg/dL Ionized CaIonized Ca2+2+ > 2.7 meq/L > 2.7 meq/L
Hypercalcemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
EtiologyEtiology– MalignancyMalignancy– EndocrinopathiesEndocrinopathies
HyperparathyroidismHyperparathyroidism PheochromocytomaPheochromocytoma Adrenal insufficiencyAdrenal insufficiency
– DrugsDrugs Hypervitaminosis D/AHypervitaminosis D/A Thiazides, LithiumThiazides, Lithium
– ImmobilizationImmobilization
Hypercalcemia
90%
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Clinical FeaturesClinical Features– GeneralGeneral
Malaise, weakness, dehydration, polydipsiaMalaise, weakness, dehydration, polydipsia
– NeurologicNeurologic Confusion, apathy, decreased memory, irritabilityConfusion, apathy, decreased memory, irritability Hallucinations, headache, ataxiaHallucinations, headache, ataxia Hyporeflexia, hypotoniaHyporeflexia, hypotonia
– CardiovascularCardiovascular HTN, dysrhythmiasHTN, dysrhythmias EKG abnormalitiesEKG abnormalities
– Short QT & ST, Wide T-waveShort QT & ST, Wide T-wave
Hypercalcemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Clinical Features (Cont)Clinical Features (Cont)– GastrointestinalGastrointestinal
N/V, anorexia, wt lossN/V, anorexia, wt loss Constipation, abdominal painConstipation, abdominal pain PUD, PancreatitisPUD, Pancreatitis
– SkeletalSkeletal Fractures, bone pain, deformitiesFractures, bone pain, deformities
– UrologicUrologic Polyuria, polydipsiaPolyuria, polydipsia Renal insufficiencyRenal insufficiency NephrolithiasisNephrolithiasis
Hypercalcemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Memory AidMemory Aid– StonesStones ---- ---- Renal CalculiRenal Calculi– BonesBones ---- ---- OsteolysisOsteolysis– MoansMoans ---- ---- Psychiatric disordersPsychiatric disorders– Groans ----Groans ---- Abdominal (PUD, Abdominal (PUD,
Pancreatitis)Pancreatitis)
Hypercalcemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
TreatmentTreatment– Treat dehydrationTreat dehydration
IV NS until ECF volume restoredIV NS until ECF volume restored Lasix 40 to 100 mg IV q 2-4 hrsLasix 40 to 100 mg IV q 2-4 hrs
– Decrease bone absorptionDecrease bone absorption CalcitoninCalcitonin MithramycinMithramycin HydrocortisoneHydrocortisone IndomethacinIndomethacin
– Monitor for hypokalemia, hypomagnesemiaMonitor for hypokalemia, hypomagnesemia
Hypercalcemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Intracellular cationIntracellular cation Normal rangeNormal range
– 1.5 to 2.5 meq/L1.5 to 2.5 meq/L
Magnesium
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Serum MgSerum Mg2+2+ < 1.5 meq/L < 1.5 meq/L Coexistent disordersCoexistent disorders
– HypokalemiaHypokalemia– HypocalcemiaHypocalcemia
Hypomagnesemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
EtiologyEtiology– RedistributionRedistribution
Trtm of DKATrtm of DKA
– Decreased intakeDecreased intake Alcoholism, malnutritionAlcoholism, malnutrition Bowel resection, malabsorptionBowel resection, malabsorption
– Extrarenal lossExtrarenal loss Lactation, sweatingLactation, sweating Burns, sepsisBurns, sepsis DiarrheaDiarrhea
Hypomagnesemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Etiology (Cont)Etiology (Cont)– Renal lossRenal loss
DrugsDrugs– Loop diuretics, Aminoglycosides, Amphotericin Loop diuretics, Aminoglycosides, Amphotericin
B, Vitamin D intoxication, Alcohol, CisplatinB, Vitamin D intoxication, Alcohol, Cisplatin SIADHSIADH Hyperthyroidism, HyperparathyroidismHyperthyroidism, Hyperparathyroidism
Hypomagnesemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Clinical FeaturesClinical Features– NeuromuscularNeuromuscular
TetanyTetany Muscle weaknessMuscle weakness Cerebellar (ataxia, nystagmus, vertigo)Cerebellar (ataxia, nystagmus, vertigo) Confusion, obtundation, comaConfusion, obtundation, coma SeizuresSeizures Apathy, depressionApathy, depression IrritabilityIrritability ParesthesiasParesthesias
Hypomagnesemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Clinical FeaturesClinical Features– GastrointestinalGastrointestinal
Dysphagia, anorexia, nauseaDysphagia, anorexia, nausea
– CardiovascularCardiovascular Heart failureHeart failure DysrhythmiasDysrhythmias HypotenstionHypotenstion EKG abnormalitiesEKG abnormalities
– Prolonged PR & QT, wide QRSProlonged PR & QT, wide QRS– Depressed ST segment, inverted T-wavesDepressed ST segment, inverted T-waves
Hypomagnesemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
TreatmentTreatment– OralOral– IV replacementIV replacement
Severe proven hypomagnesemiaSevere proven hypomagnesemia Alcoholics with DTsAlcoholics with DTs Up to 8-12 g MgSOUp to 8-12 g MgSO44 day 1, then 4-6 g/day day 1, then 4-6 g/day
– Monitor for hypokalemia, Monitor for hypokalemia, hypocalcemia, & hypophosphatemiahypocalcemia, & hypophosphatemia
Hypomagnesemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Serum MgSerum Mg2+2+ > 2.5 meq/L > 2.5 meq/L Coexistent disordersCoexistent disorders
– HyperkalemiaHyperkalemia– HypercalcemiaHypercalcemia
Hypermagnesemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
EtiologyEtiology– Renal failure (most common)Renal failure (most common)– Increased MgIncreased Mg2+2+ load load
Laxatives, antacids, enemasLaxatives, antacids, enemas Untreated DKAUntreated DKA RhabdomyolysisRhabdomyolysis
– Increased renal absorptionIncreased renal absorption HyperparathyroidismHyperparathyroidism HypothyroidismHypothyroidism Mineralocorticoid/adrenal insufficiencyMineralocorticoid/adrenal insufficiency
Hypermagnesemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Clinical FeaturesClinical Features– NauseaNausea > 2.0 meq/L > 2.0 meq/L– SomnolenceSomnolence > 3.0 meq/L > 3.0 meq/L– Decreased/absent DTRsDecreased/absent DTRs > 4.0 meq/L > 4.0 meq/L– Resp compromise, apneaResp compromise, apnea > 8.0 meq/L > 8.0 meq/L– Hypotension, heart block Hypotension, heart block ≈ 15.0 meq/L≈ 15.0 meq/L
– EKG abnormalitiesEKG abnormalities >> 5.0 meq/L 5.0 meq/L Prolonged PR & QTProlonged PR & QT Prolonged QRS durationProlonged QRS duration
Hypermagnesemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
TreatmentTreatment– D/C MgD/C Mg2+2+ administration administration– Dilution using IV NSDilution using IV NS– Lasix 40-80 mg IVLasix 40-80 mg IV– DialysisDialysis
Hypermagnesemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Intracellular anionIntracellular anion Normal rangeNormal range
– 2.5 to 4.5 mg/dL2.5 to 4.5 mg/dL
Phosphate
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Serum POSerum PO44 < 2.5 mg/dL < 2.5 mg/dL
Sx onset at POSx onset at PO44 < 1.0 mg/dL < 1.0 mg/dL
Hypophosphatemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
EtiologyEtiology– Decreased oral intakeDecreased oral intake
Malnutrition (Alcoholics)Malnutrition (Alcoholics)
– Excessive lossExcessive loss– Shift from ECF ICFShift from ECF ICF
Respiratory/Metabolic AlkalosisRespiratory/Metabolic Alkalosis
– HyperalimentationHyperalimentation– HyperparathyroidismHyperparathyroidism– DKA, AKADKA, AKA
Hypophosphatemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Clinical FeaturesClinical Features– Progressive weakness and tremorsProgressive weakness and tremors– Circumoral & fingertip paresthesiasCircumoral & fingertip paresthesias– Absent DTRsAbsent DTRs– Mental obtundationMental obtundation– HyperventilationHyperventilation– AnorexiaAnorexia
Hypophosphatemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
TreatmentTreatment– Serum POSerum PO44 level < 1.0 mg/dL level < 1.0 mg/dL
IV replacementIV replacement 2.5 mg/kg IV over 6 hours 2.5 mg/kg IV over 6 hours Check serum POCheck serum PO44 after each dose after each dose
Hypophosphatemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Complications of therapyComplications of therapy– HypocalcemiaHypocalcemia– Metastatic calcificationMetastatic calcification– HypotensionHypotension– HyperkalemiaHyperkalemia
Hypophosphatemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Serum POSerum PO44 > 4.5 mg/dL > 4.5 mg/dL EtiologyEtiology
– Decreased renal excretionDecreased renal excretion– Shift from ICF ECFShift from ICF ECF– Increased intakeIncreased intake– Most common with renal dysfunctionMost common with renal dysfunction– HypoparathyroidismHypoparathyroidism
Hyperphosphatemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Clinical FeaturesClinical Features– Sx related to renal failureSx related to renal failure– Sx of hypocalcemiaSx of hypocalcemia– Sx of hypomagnesemiaSx of hypomagnesemia
Hyperphosphatemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
TreatmentTreatment– Treat underlying causeTreat underlying cause– Restrict Calcium Phosphate intakeRestrict Calcium Phosphate intake– Dilution using IV NSDilution using IV NS– Acetazolamide 500 mg q 6 hrsAcetazolamide 500 mg q 6 hrs– Aluminum Carbonate/HydroxideAluminum Carbonate/Hydroxide
Absorbs phosphate secreted into gutAbsorbs phosphate secreted into gut
– HemodialysisHemodialysis
Hyperphosphatemia
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Things to rememberThings to remember– Treat the patient, not the lab valueTreat the patient, not the lab value– Rate of correction should mirror rate of Rate of correction should mirror rate of
changechange– Correct in orderly fashionCorrect in orderly fashion
1. Volume1. Volume 2. pH2. pH 3. Potassium, Calcium, Magnesium3. Potassium, Calcium, Magnesium 4. Sodium and Chloride4. Sodium and Chloride
– Consider impact of interventions overallConsider impact of interventions overall
Key Points
ELECTROLYTE ELECTROLYTE DISORDERSDISORDERS
Questions
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