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

 

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