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).
- Oral repletion
- 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