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Hypokalemia
Aka: Hypokalemia
- Pathophysiology
- Approximate Total body potassium = 55 meq/kg
- Serum Potassium decreased 1 meq/dl: 350 meq K+ deficit
- Serum Potassium less than 2 meq/dl: 1000 meq K+ deficit
- Symptoms and Signs (when Serum Potassium < 2.5)
- General
- Malaise
- Fatigue
- Neurologic
- Weakness
- Decreased Deep Tendon Reflexes
- Paresthesia
- Cramps
- Restless legs Syndrome
- Rhabdomyolysis
- Paralysis
- Gastrointestinal
- Constipation
- Ileus
- Exacerbated Hepatic Encephalopathy
- Cardiovascular
- Orthostatic Hypotension
- Hypertension
- Arrhythmias (especially with Digoxin use)
- Renal
- Metabolic Alkalosis
- Polyuria, Polydipsia
- Decreased GFR
- Glucose Intolerance
- Labs
- Electrocardiogram
- T Waves flattened
- Prominent U Waves
- ST depression
- Diagnosis
- Exclude Transcellular Potassium Shift
- Check 24 hour Urine Potassium and Urine Sodium
- Sample should have total Urine Sodium > 100 meq
- Interpretation
- Urine Potassium <20 meq/day
- Extrarenal Potassium Loss
- Urine Potassium >20 meq/day
- Renal Potassium Loss
- Management
- See Potassium Replacement