Electrolyte Emergencies
Hyponatremia
Decreased serum sodium Na+ <135 mEq/L
Hyponatremia
Causes
Loss
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/Symptoms
apathy secondary to cerebral edema Headache Muscle twitching, cramps Seizures Na+ < 110 mEq/L
Lethargy,
Hyponatremia
Treatment
NS
infused at a rate to restore normal sodium over 48 hours
Hypernatremia
Elevated serum sodium Na+ >150 mEq/L
Hypernatremia
Causes
water loss Diabetes insipidus Pure solute gain NaHCO3 administration
Pure
Hypernatremia
Causes
Water
loss > Solute loss Diarrhea Vomiting Sweating Osmotic diuresis
Hypernatremia
Signs/Symptoms
Irritability,
Coma Intracranial
restlessness
hemorrhage Blood sludging - thrombosis Seizures Thirst, 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 Diarrhea
losses
Vomiting
suction Urinary losses Diuretics Osmotic diuresis
NG
Hypokalemia
Causes
Intracellular Alkalosis
shifts
agents Theophylline Inadequate intake
Hypokalemia
Signs/Symptoms
hyporeflexia, paresthesias Decreased GI motility Nausea, vomiting Increased sensitivity to digitalis
Weakness,
Hypokalemia
Signs/Symptoms
changes Flat to inverted T waves U waves ST segment depression Cardiac arrhythmias Ventricular ectopy V-Fib
EKG
Hypokalemia
Treatment
underlying cause 10 mEq KCL IV over 1 hour, repeated until serum K+ > 3.5 mEq/L
Correct
Hyperkalemia
Elevated serum potassium K+ > 5.5 mEq/L K+ > 6 mEq/L - Emergency K+ > 7 mEq/L - Life Threat
Hyperkalemia
Causes
Decreased
excretion Renal failure Addison’s disease - blockers Hyperglycemia Acidosis
Hyperkalemia
Causes
Increased
intake Crush injury, burns, sepsis Massive hemolysis Blood transfusion High-dose penicillin Increased oral intake
Hyperkalemia
Signs/Symptoms
weakness Numbness, tingling EKG changes
peaked T waves Broadening of QRS; decreased P wave size “Sine wave” leading to V-Fib then asystole
Tall,
Muscle
Hyperkalemia
Treatment
- 0.5 - 1.0g Antagonizes cardiac toxicity NaHCO3 - 50 mEq Drives K+ into cells D50W (25g)/insulin (10 units regular) Drives K+ into cells
Calcium
Hypocalcemia
Decreased serum calcium Ca2+ < 8.5 mg/100ml
Hypocalcemia
Causes
Hypoparathyroidism
D deficiency Decreased dietary intake Alkalosis Massive blood transfusion Citrate toxicity
Vitamin
Hypocalcemia
Signs/Symptoms
Paresthesias Hyperreflexia,
carpopedal spasm,
tetany Seizures Trousseau’s sign: Carpopedal spasm following BP cuff compression of arm
Hypocalcemia
Signs/Symptoms
sign Contraction of facial muscles when face is tapped at angle of jaw Laryngospasms Prolonged QT interval Increased ventricular irritability
Chvostek’s
Hypocalcemia
Management
chloride 1g over 10 - 20 minutes Overly rapid administration of calcium can cause bradycardia, hypotension, and cardiac arrest
Calcium
Hypercalcemia
Increased serum calcium Ca2+ > 10.5 mg/100ml
Hypercalcemia
Causes
Malignancies
breast, lungs Hyperparathyroidism Vitamin D toxicity Addison’s disease Milk/alkali syndrome
Skeletal,
Hypercalcemia
Signs/Symptoms
fatigue, depression, coma Muscle weakness Hypertension Anorexia, nausea, abdominal pain
Apathy,
Hypercalcemia
Signs/Symptoms
stones Short QT interval, heart block, cardiac arrest “Bones, Stones, Hypertones, Abdominal moans”
Kidney
Hypercalcemia
Treatment
- 2 liters NS over 1 hour Decrease Ca2+ reabsorption Furosemide 40 mg IV Inhibits Ca2+ reabsorption Calcitonin Directly lowers Ca2+
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