What is the management of rhabdomyolysis?

Management of Rhabdomyolysis

Early aggressive intravenous fluid resuscitation is the cornerstone of rhabdomyolysis management to prevent acute kidney injury and reduce mortality. 1

Initial Assessment and Diagnosis

• Diagnosis is confirmed by elevated creatine kinase (CK) levels at least 10 times the upper limit of normal
• Monitor for clinical manifestations:
  • Muscle pain, weakness, swelling
  • Dark "tea-colored" urine (myoglobinuria)
  • Signs of acute kidney injury
  • Electrolyte abnormalities (particularly hyperkalemia)

Primary Management Strategy

Fluid Resuscitation

• Initiate aggressive intravenous fluid resuscitation immediately:
  • Target: Maintain urine output of at least 300 mL/hour 2
  • Volume: At least 6L daily for moderate rhabdomyolysis (CPK <15,000 IU/L)
  • Volume: Greater than 6L daily for severe rhabdomyolysis (CPK >15,000 IU/L) 1
  • Solution: Normal saline (0.9% NaCl) is the first-line fluid
  • Goal: Restore renal perfusion and increase urine flow to prevent myoglobin precipitation in renal tubules

Monitoring

• Measure serum creatinine, electrolytes, and CK levels every 6-12 hours initially
• Monitor fluid status with regular clinical assessment
• Target urine pH >6.5 to reduce myoglobin precipitation 1
• Continue fluid therapy until CK levels decrease to <1,000 U/L 2

Management of Complications

Acute Kidney Injury

• Monitor for signs of acute kidney injury
• Consider renal replacement therapy if:
  • Severe hyperkalemia unresponsive to medical management
  • Severe acidosis
  • Volume overload unresponsive to diuretics
  • Uremic symptoms

Electrolyte Abnormalities

• Hyperkalemia: Treat aggressively with standard protocols (calcium gluconate, insulin/glucose, sodium bicarbonate, potassium binders)
• Hypocalcemia: Monitor but typically don't treat unless symptomatic
• Hyperphosphatemia: Phosphate binders if severe
• Metabolic acidosis: May require sodium bicarbonate if severe

Compartment Syndrome

• Assess for signs of compartment syndrome:
  • Pain out of proportion to injury
  • Pain with passive stretch
  • Paresthesia and paresis
  • (Note: Pulselessness and pallor are late signs) 1
• Measure compartment pressure if suspected (>30 mmHg or differential pressure <30 mmHg is diagnostic) 1
• Early fasciotomy is required for established compartment syndrome 1

Adjunctive Therapies

Sodium Bicarbonate

• While commonly used, there is limited evidence supporting routine use 3
• Consider if patient has metabolic acidosis
• Goal: Maintain urine pH >6.5 to reduce myoglobin precipitation

Mannitol

• Evidence does not strongly support routine use 3
• Consider if urine output goals are not met despite adequate fluid resuscitation

Special Considerations

Medication Review

• Discontinue medications that may cause or worsen rhabdomyolysis:
  • Statins
  • Certain antibiotics
  • Antipsychotics
  • Other myotoxic drugs 1

Underlying Cause Management

• Identify and treat the underlying cause of rhabdomyolysis:
  • Trauma/crush injury
  • Exertional
  • Medications
  • Toxins/drugs
  • Infections
  • Metabolic disorders

Pitfalls and Caveats

1. Delayed treatment: Early fluid resuscitation is critical - mortality increases significantly with delayed intervention 1

2. Inadequate fluid resuscitation: Underestimating fluid needs can lead to preventable kidney injury

3. Fluid overload: Excessive fluid administration can lead to pulmonary edema, especially in patients with pre-existing cardiac or renal disease - requires careful monitoring

4. Missing compartment syndrome: This is a surgical emergency requiring prompt fasciotomy

5. Electrolyte management: Failure to monitor and correct electrolyte abnormalities (especially hyperkalemia) can lead to cardiac arrhythmias

6. Medication interactions: Some medications used to treat complications may interact with existing medications or exacerbate rhabdomyolysis

By following this algorithmic approach with emphasis on early aggressive fluid resuscitation, most patients with rhabdomyolysis can be successfully managed with preservation of renal function and prevention of life-threatening complications.