What is the treatment for rhabdomyolysis?

Rhabdomyolysis: Signs, Symptoms, and Treatment

The cornerstone of rhabdomyolysis treatment is immediate, aggressive intravenous fluid resuscitation with isotonic saline (0.9% NaCl) targeting a urine output of >300 mL/hour to prevent acute kidney injury. 1

Signs and Symptoms

Clinical Presentation

• Classic triad (present in <10% of cases):
  • Muscle pain
  • Muscle weakness
  • Dark urine (tea/cola-colored) 2
• Common symptoms:
  • Myalgias (muscle aches)
  • Weakness
  • Fatigue
  • Nausea/vomiting
  • Fever
  • Altered mental status (in severe cases)

Laboratory Findings

• Diagnostic threshold: Serum creatine kinase (CK) at least 10 times the upper limit of normal 1
• Key laboratory abnormalities:
  • Elevated CK (may reach >100,000 IU/L)
  • Myoglobinuria (positive urine dipstick for blood but negative microscopy for RBCs)
  • Hyperkalemia
  • Elevated creatinine/BUN (if kidney injury present)
  • Hypocalcemia (early) or hypercalcemia (later)
  • Hyperphosphatemia
  • Metabolic acidosis

Treatment Algorithm

1. Initial Management (First Hours)

• Fluid resuscitation:

  • Use isotonic saline (0.9% NaCl) - avoid potassium-containing fluids like Lactated Ringer's 1
  • Initial rate: 1-2 L/hour (adjust based on severity and cardiac status)
  • Target urine output: >300 mL/hour 1
  • Continue aggressive hydration until CK levels decrease significantly

• Identify and remove causative factors:

  • Discontinue all nephrotoxic medications (NSAIDs, ACE inhibitors/ARBs)
  • Stop causative medications (e.g., statins) immediately 1

• Monitor and manage electrolyte abnormalities:

  • Treat hyperkalemia urgently if present
  • Address symptomatic hypocalcemia only (avoid routine calcium supplementation) 1
  • Monitor potassium, calcium, phosphorus, and magnesium levels every 6-12 hours 1

2. Ongoing Management

• Laboratory monitoring:

  • Check CK, electrolytes, and renal function every 6-12 hours in acute phase 1
  • Monitor urine output hourly
  • Arterial blood gas to assess for metabolic acidosis 1

• Renal protection:

  • Continue fluid resuscitation until CK levels decrease significantly
  • Nephrology consultation for all cases with acute kidney injury 1
  • Consider renal replacement therapy for:
    • Severe hyperkalemia unresponsive to medical management
    • Severe acidosis
    • Volume overload unresponsive to diuretics
    • Uremic symptoms

• Compartment syndrome management:

  • Monitor for signs: pain, tension, paresthesia, paresis
  • Measure compartment pressure if suspected (threshold >30 mmHg) 1
  • Urgent surgical consultation for fasciotomy if confirmed

3. Prevention of Complications

• Acute kidney injury prevention:

  • Maintain aggressive hydration
  • Avoid nephrotoxins
  • Monitor renal function

• Electrolyte management:

  • Treat hyperkalemia with calcium gluconate, insulin/glucose, sodium bicarbonate, or dialysis if severe
  • Monitor for rebound hypercalcemia during recovery phase

• Other complications:

  • Monitor for disseminated intravascular coagulation
  • Watch for liver dysfunction
  • Assess for cardiac arrhythmias (secondary to electrolyte abnormalities)

Special Considerations

Exertional Rhabdomyolysis

• Properly train during transition periods to prevent exertional rhabdomyolysis 3
• Limit volume and intensity of activity during first 4 days of transition periods 3
• Avoid "too much, too soon, too fast" in workout regimens 3
• Have venue-specific emergency action plans for exertional rhabdomyolysis 3

Post-surgical Management

• Monitor for myonecrosis and subsequent rhabdomyolysis 3
• Watch for reddish urine without explanation
• Provide adequate hydration, forced diuresis, and urine alkalinization if myoglobinuria develops 3

Recurrent Rhabdomyolysis

• Investigate for underlying genetic disorders if recurrent episodes occur 1
• Consider genetic testing for:
  • Glycogen storage diseases
  • Fatty acid oxidation disorders
  • Mitochondrial disorders
  • Muscular dystrophies
  • Ion channelopathies 1

Common Pitfalls to Avoid

1. Delayed recognition - Don't wait for the classic triad; most patients don't present with all three symptoms
2. Inadequate fluid resuscitation - Underestimating fluid needs is common
3. Using potassium-containing fluids - Can worsen hyperkalemia
4. Routine use of bicarbonate or mannitol - Limited evidence for benefit 4, 5
5. Missing compartment syndrome - Can lead to permanent muscle damage
6. Failure to identify and remove the underlying cause - Essential to prevent recurrence
7. Premature discontinuation of fluid therapy - Continue until CK levels decrease significantly

By following this evidence-based approach to rhabdomyolysis management, focusing on early recognition, aggressive fluid resuscitation, and careful monitoring, you can significantly reduce the risk of acute kidney injury and other complications.