1365. Effects of hypocalcemia // Rx of hypoCa // How much calcium in the two preparations? // 90% cases of hypercalcemia are secondary to which two causes? // Bryan Hayes Electrolyte Replacement

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Bryan Hayes / EMRAP Electrolyte Replacement

  • Potassium repletion
    • Oral repletion
      • Use the oral route as long as the patient can take medication orally and their GI tract is working.
      • Potassium chloride
        • Comes as immediate release packet and extended release tabs
        • Unpleasant taste is a major issue
        • May be more beneficial if patient is chloride depleted
        • Typical dosing: 40-60 mEq PO
      • Potassium bicarbonate
        • Effervescent tab typically comes as 25 mEq
        • More palatable than potassium chloride
        • May be more beneficial in patients with metabolic acidosis
        • Typical dosing: 50 mEq PO
    • Intravenous repletion
      • Works more rapidly than oral potassium
      • Indications
        • Serum concentration < 3.0 mEq/L
        • Patient not tolerating PO
        • Moderate to severe symptoms
        • ECG changes from hypokalemia
      • Central access allows for more rapid administration.
        • Most institutions have protocols setting a maximum infusion rate (typically 20 mEq/hour through a peripheral IV and 60 mEq/hour through a central line).
  • Magnesium supplementation
    • “HypoK = HypoMg” (a mantra from Dr. Corey Slovis)
    • Repletion of magnesium is critical in repleting potassium.
      • Oral: Magnesium oxide 400-800 mg tablet
      • IV: Magnesium sulfate 2-4 g
    • Recheck labs
      • Oral repletion: After 60 minutes
      • IV repletion: After 30-60 minutes
    • Home supplementation
      • Potassium rich foods
      • Can use either potassium chloride or potassium bicarbonate
  • Magnesium repletion
    • Mg 1.6 – 1.9 mEq/L: Give Magnesium sulfate 1-2 g IV
    • Mg 1.0 – 1.4 mEq/L: Give Magnesium sulfate 2-4 g IV
    • Mg < 1.0 mEq/L: Give Magnesium sulfate 4-8 g IV
    • Caution with outpatient supplementation if patient has renal insufficiency
  • Calcium repletion
    • Sick patient: IV calcium gluconate 2 g over an hour
    • Non-sick patient: Oral supplementation with calcium carbonate
  • Phosphate repletion
    • Typically will replete if phosphate < 1.0 mEq/L
    • Sick patient
      • IV repletion
      • Potassium phosphate (if serum potassium is low) or sodium phosphate (if serum potassium is high)
      • Can give 15, 30, or 45 mmol depending on how low phosphate level is.
      • Typically given at about 15 mmol/h
    • Non-sick patient
      • Oral repletion
      • Potassium phosphate or sodium phosphate 250 mg PO