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Source: Brophy DF, Frumin J. Disorders of Potassium and Magnesium Homeostasis. In: DiPiro, JT, Talbert RL, Yee GC, Matzke GR, Wells BG, Posey LM. Pharmacotherapy: A Pathophysiologic Approach. 8th ed. http://www.accesspharmacy.com/content.aspx?aid=7983818. Accessed August 21, 2012.

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  • Serum potassium >5.0 mEq/L (>5.0 mmol/L)
    • Mild: serum potassium 5.1–5.9 mEq/L (5.1–5.9 mmol/L)
    • Moderate: serum potassium 6.0–7.0 mEq/L (6.0–7.0 mmol/L)
    • Severe: serum potassium >7.0 mEq/L (>7.0 mmol/L)

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  • Develops when potassium intake exceeds excretion or when transcellular distribution of potassium disturbed.

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  • Increased potassium intake (e.g., use of salt substitutes by dialysis patients containing 10–15 mEq (10–15 mmol) potassium per gram)
  • Decreased renal potassium excretion
    • Kidneys excrete 80% of daily potassium intake.
    • Potassium retained in acute kidney injury (AKI) or with chronic kidney disease (CKD)
    • Hyperkalemia results from dose-dependent drug effects on kidney regulation:
      • Angiotensin-converting enzyme inhibitors (ACEIs)
      • Angiotensin-II receptor blockers (ARBs)
      • Potassium-sparing diuretics
      • Prostaglandin inhibitors (e.g., nonsteroidal anti-inflammatory drugs [NSAIDs])
  • Tubular unresponsiveness to aldosterone
  • Redistribution of potassium to extracellular space

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  • Less common than hypokalemia
  • Incidence in hospitalized patients: 1.4–10%

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  • Dietary potassium restrictions for patients with stages 4 or 5 CKD and dialysis patients
  • Use ACEIs, ARBs, potassium-sparing diuretics and NSAIDs cautiously in patients with underlying heart or liver failure or CKD.
    • Monitor serum potassium within 1 week of drug initiation or dosage increase.

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  • Age: More common in elderly patients with renal insufficiency
  • Acute and chronic kidney disease

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Signs and Symptoms

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  • Often asymptomatic; may be nonspecific and related to muscular or cardiac function
  • Muscle weakness
  • Fatigue
  • Palpitations
  • Electrocardiogram (ECG) changes include:
    • Peaked T wave
    • Widened PR interval and QRS complex
    • Loss of P wave
    • Sine-wave appearance

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Means of Confirmation and Diagnosis

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  • Serum potassium >5.0 mEq/L (>5.0 mmol/L)

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Laboratory Tests

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  • Metabolic panel
    • Serum potassium
    • Serum creatinine

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Diagnostic Procedures

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  • ECG

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Differential Diagnosis

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  • Diabetes mellitus
  • Rhabdomyolysis
  • Tumor lysis syndrome
  • Hemolysis

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  • Antagonize adverse cardiac effects.
  • Reverse signs and symptoms.
  • Return serum and total-body stores of potassium to normal.

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  • Determined by severity of hyperkalemia, rapidity of development and patient’s clinical condition (Figure 1).

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Figure 1.
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Treatment approach for hyperkalemia. Serum potassium of 5.5 mEq/L equivalent to 5.5 mmol/L. Reprinted with permission from Wells BG, DiPiro JT, Schwinghammer TL, et al. Pharmacotherapy Handbook. 8th ed. New York: McGraw-Hill, 2012.

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  • Asymptomatic patients with mild hyperkalemia: dietary education to control intake
  • Dialysis most rapid way to lower serum potassium concentration.

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  • Symptomatic patients or severe hyperkalemia
    • Acute ECG changes
      • Administer IV calcium chloride or gluconate 1 g to reverse ECG manifestations and arrhythmias.
        • Duration of action: 30–60 minutes; repeat based on ECG findings.
      • Administer drugs to cause intracellular shift of potassium (Figure 1, Table 1)
        • Insulin and dextrose
        • Sodium bicarbonate
        • Albuterol

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Table Graphic Jump Location
Table 1. Therapeutic Alternatives for Management of Hyperkalemia

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