Electrolyte Emergencies

BYPROF/ GOUDA ELLABBAN

Hyponatremia

Decreased serum sodium

Na+ <135 mEq/L

Hyponatremia

CausesLoss of salt and water

Diuretics Addison’s disease Osmotic diuresis (DKA) Vomiting Diarrhea Diaphoresis

Hyponatremia Causes

Increase in body water (dilutional hyponatremia) Excess water intake (water intoxication) CHF Renal failure Cirrhosis

Hyponatremia

Signs/SymptomsLethargy, apathy secondary to cerebral

edemaHeadacheMuscle twitching, crampsSeizures

Na+ < 110 mEq/L

Hyponatremia

TreatmentNS infused at a rate to restore normal

sodium over 48 hours

Hypernatremia

Elevated serum sodium

Na+ >150 mEq/L

Hypernatremia

CausesPure water loss

Diabetes insipidus

Pure solute gain NaHCO3 administration

Hypernatremia

CausesWater loss > Solute loss

Diarrhea Vomiting Sweating Osmotic diuresis

Hypernatremia Signs/Symptoms

Irritability, restlessnessComa Intracranial hemorrhageBlood sludging - thrombosisSeizuresThirst, dry mucus membranes, poor skin

turgor

Hypernatremia

Treatment Infusion of D5W (free water) to correct

water deficit over 48 hours

Hypokalemia

Decreased serum potassium

K+ < 3.5 mEq/L

Hypokalemia Causes

Gastrointestinal losses Diarrhea Vomiting NG suction

Urinary losses Diuretics Osmotic diuresis

Hypokalemia

Causes Intracellular shifts

Alkalosis β agents Theophylline

Inadequate intake

Hypokalemia

Signs/SymptomsWeakness, hyporeflexia, paresthesiasDecreased GI motility Nausea, vomiting Increased sensitivity to digitalis

Hypokalemia Signs/Symptoms

EKG changes Flat to inverted T waves U waves ST segment depression

Cardiac arrhythmias Ventricular ectopy V-Fib

Hypokalemia

TreatmentCorrect underlying cause10 mEq KCL IV over 1 hour, repeated

until serum K+ > 3.5 mEq/L

Hyperkalemia

Elevated serum potassium

K+ > 5.5 mEq/L

K+ > 6 mEq/L - Emergency

K+ > 7 mEq/L - Life Threat

Hyperkalemia

CausesDecreased excretion

Renal failure Addison’s disease β - blockers Hyperglycemia Acidosis

Hyperkalemia

Causes Increased intake

Crush injury, burns, sepsis Massive hemolysis Blood transfusion High-dose penicillin Increased oral intake

Hyperkalemia Signs/Symptoms

Muscle weaknessNumbness, tinglingEKG changes

Tall, peaked T waves Broadening of QRS; decreased P wave size “Sine wave” leading to V-Fib then asystole

Hyperkalemia

TreatmentCalcium - 0.5 - 1.0g

Antagonizes cardiac toxicity

NaHCO3 - 50 mEq Drives K+ into cells

D50W (25g)/insulin (10 units regular) Drives K+ into cells

Hypocalcemia

Decreased serum calcium

Ca2+ < 8.5 mg/100ml

Hypocalcemia

CausesHypoparathyroidismVitamin D deficiencyDecreased dietary intakeAlkalosisMassive blood transfusion

Citrate toxicity

Hypocalcemia Signs/Symptoms

ParesthesiasHyperreflexia, carpopedal spasm,

tetanySeizuresTrousseau’s sign:

Carpopedal spasm following BP cuff compression of arm

Hypocalcemia

Signs/SymptomsChvostek’s sign

Contraction of facial muscles when face is tapped at angle of jaw

LaryngospasmsProlonged QT interval Increased ventricular irritability

Hypocalcemia

ManagementCalcium chloride

1g over 10 - 20 minutes

Overly rapid administration of calcium can cause bradycardia, hypotension, and cardiac arrest

Hypercalcemia

Increased serum calcium

Ca2+ > 10.5 mg/100ml

Hypercalcemia

CausesMalignancies

Skeletal, breast, lungs

HyperparathyroidismVitamin D toxicityAddison’s diseaseMilk/alkali syndrome

Hypercalcemia

Signs/SymptomsApathy, fatigue, depression, comaMuscle weaknessHypertensionAnorexia, nausea, abdominal pain

Hypercalcemia

Signs/SymptomsKidney stonesShort QT interval, heart block, cardiac

arrest“Bones, Stones, Hypertones, Abdominal

moans”

Hypercalcemia

Treatment1 - 2 liters NS over 1 hour

Decrease Ca2+ reabsorption

Furosemide 40 mg IV Inhibits Ca2+ reabsorption

Calcitonin Directly lowers Ca2+