What is the treatment for Rhabdomyolysis (muscle breakdown disease)?

Treatment of Rhabdomyolysis

Immediately initiate aggressive intravenous fluid resuscitation with isotonic saline (0.9% NaCl), targeting a urine output of 300 mL/hour, as this is the cornerstone of treatment to prevent acute kidney injury by facilitating myoglobin clearance and preventing renal tubular obstruction. 1, 2, 3, 4

Immediate Fluid Management

• Start isotonic saline (0.9% NaCl) immediately upon diagnosis—delayed treatment significantly increases the risk of acute kidney injury and mortality. 1, 2

• For severe rhabdomyolysis (CK >15,000 IU/L), administer more than 6L of fluid per day; for moderate cases (CK 5,000-15,000 IU/L), give 3-6L per day. 1, 2

• Continue IV fluids until CK levels decline below 1,000 U/L and renal function stabilizes. 4

• Monitor closely for fluid overload, particularly in patients with cardiac or renal compromise. 2

Discontinue All Causative Agents

• Immediately stop all potentially causative medications, including statins, which are the most common drug-related cause with an incidence of 1.6 per 100,000 patient-years. 1, 2

• Discontinue dietary supplements including red yeast rice (contains lovastatin), creatine monohydrate, wormwood oil, licorice, and Hydroxycut. 1, 2

• Avoid succinylcholine in anesthesia settings as it can cause rhabdomyolysis and hyperkalemia in myopathic patients. 5, 2

Electrolyte Monitoring and Correction

• Check electrolyte panels every 6-12 hours in severe cases, with particular attention to potassium, as hyperkalemia can precipitate life-threatening cardiac arrhythmias and arrest. 1, 2

• Perform repeated bioassessment including plasma myoglobin, CK, and potassium measurements. 1, 2

• Correct significant hyperkalemia immediately to prevent cardiac complications. 1, 2

• Monitor and correct hypocalcemia and hyperphosphatemia. 2

• Assess for metabolic acidosis via arterial blood gas, which commonly occurs in severe cases. 2

Pain Management Algorithm

• Use acetaminophen (500-1000 mg, maximum 4-6 grams daily) as first-line analgesic, as it avoids nephrotoxic effects that are particularly problematic in rhabdomyolysis patients already at high risk for acute kidney injury. 1, 2

• Avoid all NSAIDs (ibuprofen, ketoprofen, diclofenac, naproxen, mefenamic acid) due to their gastrointestinal and renal toxicity. 1, 2

• Reserve opioids for severe muscle pain unresponsive to acetaminophen; use oral morphine (20-40 mg for opioid-naive patients) as first choice. 1, 2

• In patients with established acute kidney injury (eGFR <30 mL/min), use fentanyl or buprenorphine as the safest opioid choices. 1, 2

Compartment Syndrome Surveillance

• Maintain high suspicion for compartment syndrome, which can both cause and complicate rhabdomyolysis—early signs include pain, tension, paresthesia, and paresis. 1, 2

• Late signs (pulselessness and pallor) indicate irreversible damage. 1, 2

• Perform early fasciotomy when compartment pressure exceeds 30 mmHg or when differential pressure (diastolic BP minus compartment pressure) is <30 mmHg. 1, 2

Renal Replacement Therapy Indications

• Consider renal replacement therapy for refractory hyperkalemia, severe metabolic acidosis, or progressive acute kidney injury despite adequate hydration. 2

• Initiate RRT if CK remains persistently elevated despite 4 days of adequate hydration in severe cases. 2

• Discontinue RRT when urine output recovers adequately (>100 mL/day). 2

Critical Pitfalls to Avoid

• Do not delay fluid resuscitation—this is the single most important factor associated with worse outcomes and higher risk of acute kidney injury. 2, 3

• Do not use inadequate fluid volumes, as this may fail to prevent renal complications. 2

• Do not miss compartment syndrome, particularly in traumatic or severe exertional cases, as this leads to irreversible muscle and nerve damage. 2

• Do not use bicarbonate or mannitol routinely—these lack strong evidence for improved outcomes and should only be considered in specific circumstances (acidosis or inadequate urine output despite fluids). 3, 4

Admission and Monitoring

• Most patients require hospitalization for close monitoring of renal function, electrolytes, and CK levels. 3

• Trend CK, creatinine, and electrolytes daily until CK is declining and renal function is stable. 1

• The classic triad of myalgia, weakness, and dark urine is seen in less than 10% of patients, so maintain high clinical suspicion even with non-specific symptoms. 6

Etiology-Specific Considerations

• For recurrent rhabdomyolysis, history of exercise intolerance, or positive family history of neuromuscular disorders, consider genetic testing including RYR1, CACNA1S, CPT2, PYGM, ACADM, AMPD1, and VLCAD genes. 1

• For exertional rhabdomyolysis, proper calibration of training and conditioning, especially during transition periods, is essential for prevention. 1, 7