Intravenous Potassium Chloride Administration for Hypokalemia
For hypokalemia requiring IV correction, administer potassium chloride at a maximum rate of 10 mEq/hour (not exceeding 200 mEq/24 hours) when serum potassium is >2.5 mEq/L, but in severe/life-threatening hypokalemia (<2.0 mEq/L with ECG changes or cardiac arrhythmias), rates up to 40 mEq/hour (maximum 400 mEq/24 hours) can be used with continuous cardiac monitoring. 1
Indications for IV Potassium
IV potassium is indicated for:
- Severe hypokalemia (K+ ≤2.5 mEq/L) 2
- ECG abnormalities (ST depression, T wave flattening, prominent U waves, prolonged QT) 2
- Active cardiac arrhythmias (ventricular tachycardia, torsades de pointes, ventricular fibrillation) 2
- Severe neuromuscular symptoms (muscle paralysis, respiratory compromise) 1
- Non-functioning gastrointestinal tract 2
Standard Administration Protocol
Concentration and Route
- Peripheral IV: Maximum concentration 200 mEq/L (20 mEq in 100 mL) 3
- Central line preferred: Allows thorough dilution by bloodstream and avoids extravasation pain 1
- Highest concentrations (300-400 mEq/L): Must be administered exclusively via central route 1
Standard Infusion Rates (K+ >2.5 mEq/L)
- Maximum rate: 10 mEq/hour 1
- Maximum 24-hour dose: 200 mEq 1
- Typical protocol: 20 mEq KCl in 100 mL normal saline over 1 hour via central line 4, 3, 5
- Expected increase: Approximately 0.25-0.5 mEq/L per 20 mEq dose 3, 2
Urgent/Severe Hypokalemia Protocol (K+ <2.0 mEq/L)
When serum potassium is <2.0 mEq/L with ECG changes or life-threatening arrhythmias:
- Rate: Up to 40 mEq/hour 1
- Maximum 24-hour dose: 400 mEq 1
- Cardiac arrest scenario: 10 mEq/100 mL over 5 minutes has been proposed, though evidence is limited 6
Critical Monitoring Requirements
Continuous Cardiac Monitoring Required When:
- Administering rates >10 mEq/hour 1
- Serum K+ <2.0 mEq/L 1
- Patient on digitalis 2
- Baseline ECG abnormalities present 2
- Using concentrated solutions (>200 mEq/L) 1
Laboratory Monitoring
- Recheck potassium: 1-2 hours after IV correction 2
- Concurrent magnesium: Check and correct to >0.6 mmol/L, as hypomagnesemia makes hypokalemia refractory to treatment 2
- Renal function: Verify adequate urine output before initiating potassium infusion 2
Essential Safety Measures
Administration Requirements
- Use calibrated infusion device only - never push IV potassium 1
- Do not add supplementary medications to potassium solutions 1
- Use final filter during administration when possible 1
- Remove concentrated KCl from clinical areas - store only in locked cupboards in critical care 2
- Institute double-check policy for all potassium administration 2
Contraindications and Cautions
- Renal insufficiency: Dramatically increases hyperkalemia risk and potential for life-threatening complications 1
- Inadequate urine output: Delay potassium until adequate renal function established 2
- Concurrent RAAS inhibitors: Increases hyperkalemia risk, requires closer monitoring 2
Special Clinical Scenarios
Diabetic Ketoacidosis
- Add 20-30 mEq/L potassium (2/3 KCl and 1/3 KPO4) to each liter of IV fluid once K+ <5.5 mEq/L with adequate urine output 2
- If K+ <3.3 mEq/L: Delay insulin therapy until potassium restored 2
- Monitor every 2-4 hours during active treatment 2
Cardiac Arrest from Hypokalemia
- Rapid administration warranted: 10 mEq/100 mL over 5 minutes if hypokalemia identified as arrest cause 6
- Standard ACLS protocols apply, but bolus potassium administration during active CPR remains controversial with limited evidence 2, 6
Common Pitfalls to Avoid
- Never administer IV potassium as a bolus push - always use controlled infusion device 1
- Do not correct potassium without checking magnesium first - most common reason for treatment failure 2
- Avoid peripheral administration of concentrated solutions - causes severe pain and phlebitis 1
- Do not use flexible containers in series connections - risk of air embolism 1
- Never exceed 40 mEq/hour without continuous cardiac monitoring - risk of cardiac arrest 1
- Waiting too long to recheck potassium after IV administration can lead to undetected hyperkalemia 2