Electrolyte Emergencies

Decreased serum sodium Na+ <135 mEq/L 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 Lethargy, apathy secondary to cerebral edema Headache Muscle twitching, cramps Seizures Na+ < 110 mEq/L

Hyponatremia Treatment NS infused at a rate to restore normal sodium over 48 hours

Elevated serum sodium Na+ >150 mEq/L Hypernatremia Elevated serum sodium Na+ >150 mEq/L

Hypernatremia Causes Pure water loss Diabetes insipidus Pure solute gain NaHCO3 administration

Hypernatremia Causes Water loss > Solute loss Diarrhea Vomiting Sweating Osmotic diuresis

Hypernatremia Signs/Symptoms Irritability, restlessness Coma Intracranial 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

Decreased serum potassium K+ < 3.5 mEq/L 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  agents Theophylline Inadequate intake

Hypokalemia Signs/Symptoms Weakness, hyporeflexia, paresthesias Decreased 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 Treatment Correct underlying cause 10 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 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 Muscle weakness Numbness, tingling EKG changes Tall, peaked T waves Broadening of QRS; decreased P wave size “Sine wave” leading to V-Fib then asystole

Hyperkalemia Treatment Calcium - 0.5 - 1.0g Antagonizes cardiac toxicity NaHCO3 - 50 mEq Drives K+ into cells D50W (25g)/insulin (10 units regular)

Decreased serum calcium Ca2+ < 8.5 mg/100ml Hypocalcemia Decreased serum calcium Ca2+ < 8.5 mg/100ml

Hypocalcemia Causes Hypoparathyroidism Vitamin D deficiency Decreased dietary intake Alkalosis Massive blood transfusion Citrate toxicity

Hypocalcemia Signs/Symptoms Paresthesias Hyperreflexia, carpopedal spasm, tetany Seizures Trousseau’s sign: Carpopedal spasm following BP cuff compression of arm

Hypocalcemia Signs/Symptoms Chvostek’s sign Contraction of facial muscles when face is tapped at angle of jaw Laryngospasms Prolonged QT interval Increased ventricular irritability

Hypocalcemia Management Calcium chloride 1g over 10 - 20 minutes Overly rapid administration of calcium can cause bradycardia, hypotension, and cardiac arrest

Increased serum calcium Ca2+ > 10.5 mg/100ml Hypercalcemia Increased serum calcium Ca2+ > 10.5 mg/100ml

Hypercalcemia Causes Malignancies Skeletal, breast, lungs Hyperparathyroidism Vitamin D toxicity Addison’s disease Milk/alkali syndrome

Hypercalcemia Signs/Symptoms Apathy, fatigue, depression, coma Muscle weakness Hypertension Anorexia, nausea, abdominal pain

Hypercalcemia Signs/Symptoms Kidney stones Short QT interval, heart block, cardiac arrest “Bones, Stones, Hypertones, Abdominal moans”

Hypercalcemia Treatment 1 - 2 liters NS over 1 hour Decrease Ca2+ reabsorption Furosemide 40 mg IV Inhibits Ca2+ reabsorption Calcitonin Directly lowers Ca2+