Definition
- Level below 3.4 mmol/L
Causes
- Malnutrition (severe)
- Increased gastrointestinal losses (e.g., vomiting, diarrhea)
- Increased skin losses (e.g., excessive sweating, burns)
- Increased renal losses (e.g., Fanconi syndrome, RTA, diuretic therapy)
- Alkalosis (metabolic and respiratory)
- Excess insulin (increases cellular uptake of potassium)
- Medications
- Diuretics (except for potassium-sparing ones)
- Insulin
- Albuterol
Presentation
Neuromuscular Signs
- Weakness, paralysis, tetany, ileus, ureteral aperistalsis, lethargy, confusion, autonomically mediated hypotension, and rhabdomyolysis.
Cardiovascular Signs
- Elevated blood pressure, bradyarrhythmia, and tachyarrhythmia.
Renal and Metabolic Abnormalities
- Hypokalemic nephropathy, and impaired insulin secretion (glucose intolerance).
Lab Tests
- Chemistry for other electrolytes
- Glucose level
- Urinalysis, urine potassium, and creatinine
- ECG
Treatment of Hypokalemia
Orally
- Bananas, tomatoes, and most other fruits, prune juice, and orange juice.
- Oral supplements: 2 mmol/kg/day in divided doses.
Severe or Symptomatic Hypokalemia
- IV potassium, dose not to exceed 0.3 to 0.5 mEq/kg/hour.
Very Important: Ensure intact urine output prior to administration of intravenous potassium. Close cardiac monitoring is critical.Z
ECG Findings
- T wave inversion
- ST depression
- Prominent U wave
