Admitting Orders for a Patient with Hypokalemia
Patients with hypokalemia (serum potassium <3.5 mEq/L) should be admitted for monitoring and treatment when levels are ≤2.0 mEq/L or when associated with cardiac or neuromuscular symptoms, as these represent potentially unstable metabolic conditions requiring multiple disciplinary intervention and frequent monitoring. 1
Admit
- Admit to telemetry unit for patients with moderate hypokalemia (K+ 2.5-2.9 mEq/L) or severe hypokalemia (K+ <2.5 mEq/L) due to risk of cardiac arrhythmias 1
- Consider ICU admission for severe hypokalemia (K+ <2.0 mEq/L) or patients with ECG changes, neuromuscular symptoms, or hemodynamic instability 1, 2
- Primary diagnosis: Hypokalemia 3
- Secondary diagnoses: Document underlying cause (diuretic use, gastrointestinal losses, renal losses, etc.) 4
IVF
For moderate hypokalemia (K+ 2.5-2.9 mEq/L) without severe symptoms:
For severe hypokalemia (K+ <2.5 mEq/L) or with ECG changes/neuromuscular symptoms:
Diet
- Regular diet with potassium-rich foods 3
- Avoid high sodium intake which can worsen potassium excretion 2
- Consider dietary consultation for education on potassium-rich food choices 3
Laboratory and Imaging
- Baseline labs: Complete metabolic panel, magnesium, phosphorus, CBC 2
- ECG on admission and after potassium correction 1
- Urinary potassium, chloride, creatinine, and osmolality if cause is unclear 6
- Serum potassium every 4-6 hours during IV replacement, then daily until stable 2
- Magnesium level (hypomagnesemia can make hypokalemia resistant to correction) 1, 2
- Additional labs based on suspected etiology (renin, aldosterone, cortisol if endocrine cause suspected) 4, 7
Medications
- Oral potassium chloride 20-60 mEq/day for mild hypokalemia or maintenance after IV correction 2
- Consider potassium-sparing diuretics (spironolactone 25-100 mg daily, amiloride 5-10 mg daily, or triamterene 50-100 mg daily) for patients with persistent diuretic-induced hypokalemia 2
- Hold medications that worsen hypokalemia (thiazide/loop diuretics, amphotericin B, etc.) 2
- If digoxin is being used, monitor closely as hypokalemia increases risk of digoxin toxicity 2
- Correct hypomagnesemia if present (IV magnesium sulfate) 1, 2
Special Orders
- Continuous cardiac monitoring for moderate to severe hypokalemia (K+ <3.0 mEq/L) 1
- Strict intake and output monitoring 6
- Daily weights 1
- Avoid medications that can cause transcellular potassium shifts (insulin, beta-agonists) without appropriate potassium replacement 2
- Check serum potassium and renal function within 1 week after restarting diuretics if applicable 2
- Target serum potassium in the 4.0-5.0 mEq/L range, with closer to 4.5-5.0 mEq/L for cardiac patients 2
Pitfalls to Avoid
- Administering potassium too rapidly can cause cardiac arrhythmias and cardiac arrest 5
- Failing to correct hypomagnesemia will make hypokalemia resistant to correction 2
- Administering digoxin before correcting hypokalemia significantly increases risk of life-threatening arrhythmias 2
- Restarting potassium-wasting diuretics without appropriate monitoring and supplementation 2
- Inadequate monitoring of serum potassium during replacement therapy 5