What is the management of Rhabdomyolysis?

Management of Rhabdomyolysis

The cornerstone of rhabdomyolysis management is aggressive intravenous fluid resuscitation, with volumes greater than 6L required for severe cases (CK >15,000 IU/L) and 3-6L per day for moderate cases, initiated as early as possible to prevent acute kidney injury. 1, 2

Diagnosis and Assessment

• Rhabdomyolysis is diagnosed when creatine kinase (CK) levels exceed five times the upper limit of normal (approximately 1000 IU/L), with myoglobin having an earlier peak plasma concentration making it more sensitive for early detection 2
• Clinical presentation ranges from asymptomatic enzyme elevations to life-threatening complications including acute kidney injury, severe electrolyte abnormalities, compartment syndrome, and disseminated intravascular coagulation 3
• Laboratory assessment should include:
  • Plasma myoglobin and CK measurements 1
  • Complete electrolyte panel (particularly potassium, calcium, phosphorus, and magnesium) 1
  • Renal function tests 1
  • Liver function tests 1
  • Coagulation studies to evaluate for disseminated intravascular coagulation 1
  • Arterial blood gas analysis to assess for metabolic acidosis 1

Treatment Algorithm

Immediate Management

• Begin aggressive IV fluid resuscitation immediately 1, 4:
  • For severe rhabdomyolysis (CK >15,000 IU/L): >6L of fluid per day
  • For moderate cases: 3-6L per day
  • Target urine output of 300 mL/hour 3, 5
• Monitor and correct significant electrolyte abnormalities, particularly hyperkalemia which can lead to cardiac arrhythmias 1, 6
• For patients with myoglobin >600 ng/mL, maintain urine pH at 6.5 2

Monitoring

• Perform repeated bioassessment including plasma myoglobin, CK, and electrolytes 1
• Monitor urine output hourly 2
• Assess for compartment syndrome, with early signs including pain, tension, paresthesia, and paresis 1, 6
• Late signs of compartment syndrome include pulselessness and pallor, which often indicate irreversible damage 1

Compartment Syndrome Management

• Consider fasciotomy when compartment pressure exceeds 30 mmHg or when differential pressure (diastolic blood pressure – compartment pressure) is <30 mmHg 1, 6
• Early fasciotomy is indicated for established compartment syndrome 1

Cause-Specific Management

• Identify and address underlying causes of rhabdomyolysis, which may include 7, 3:
  • Trauma or direct injury
  • Excessive muscle activity
  • Hereditary muscle enzyme defects
  • Drugs and toxins (particularly statins)
  • Muscle hypoxia
  • Metabolic and endocrine disorders
  • Infections
  • Temperature alterations
• For statin-associated rhabdomyolysis, discontinue statin therapy immediately 6
• For immune checkpoint inhibitor-induced myositis with rash, consider high-dose corticosteroids 6
• For infectious causes, administer appropriate antimicrobial therapy based on suspected pathogen 6

Prevention of Complications

• Early fluid resuscitation is critical, as delayed treatment is associated with higher risk of acute kidney injury 1, 4
• In crush syndrome, CK levels above 75,000 IU/L correlate with a high incidence (>80%) of acute kidney injury 2
• Avoid medications that can exacerbate rhabdomyolysis, particularly succinylcholine 1
• Consider renal replacement therapy for severe cases with significant renal impairment 6

Special Considerations

• For exertional rhabdomyolysis, proper calibration of training and conditioning is recommended, especially during transition periods 1, 6
• Maintain adequate hydration throughout the perioperative period for surgical patients 1
• For perioperative patients, consider discontinuation of dietary supplements associated with theoretical or known higher risk for myositis or rhabdomyolysis 8