Management 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 single most critical intervention to prevent acute kidney injury and improve outcomes. 1, 2
Immediate Fluid Resuscitation
Start isotonic saline immediately upon diagnosis—delayed treatment significantly increases acute kidney injury risk and worsens outcomes. 1, 2
For severe rhabdomyolysis (CK >15,000 IU/L), administer more than 6L of fluid per day; for moderate cases (CK typically between 5,000-15,000 IU/L), give 3-6L per day. 1, 2
Avoid hypotonic solutions such as Ringer's lactate, particularly if there is any concern for head trauma in the setting of traumatic rhabdomyolysis. 1
Monitor closely for fluid overload, particularly in patients with cardiac or renal compromise. 2
Continue intravenous fluids until CK levels decline below 1,000 U/L. 3
Electrolyte Monitoring and Correction
Check electrolyte panels every 6-12 hours in severe cases, including plasma myoglobin, CK, and potassium measurements. 1, 2
Correct hyperkalemia emergently—it can precipitate life-threatening cardiac arrhythmias, pulseless electrical activity, and cardiac arrest. 1, 2
Obtain an ECG immediately to identify cardiac manifestations of hyperkalemia. 1
Monitor and correct hypocalcemia and hyperphosphatemia as they develop. 2
Assess for metabolic acidosis via arterial blood gas analysis, which commonly occurs in severe rhabdomyolysis. 1, 2
Trend CK, creatinine, and electrolytes daily until CK is declining and renal function is stable. 1
Discontinue All Causative Agents
Immediately discontinue statins and all prescription medications that may contribute to rhabdomyolysis. 1, 2
Stop dietary supplements including red yeast rice (containing lovastatin), creatine monohydrate, wormwood oil, licorice, and Hydroxycut. 1, 2
Avoid NSAIDs (ibuprofen, ketoprofen, diclofenac, naproxen, mefenamic acid) due to their nephrotoxic effects in patients already at high risk for acute kidney injury. 1, 2
In anesthesia settings, avoid succinylcholine and inhaled anesthetics in patients with muscular dystrophy or at-risk populations. 1, 2
Compartment Syndrome Surveillance
Maintain high suspicion for compartment syndrome, which can both cause and complicate rhabdomyolysis. 1, 2
Monitor for early signs: pain, tension, paresthesia, and paresis. 1, 2
Late signs (pulselessness and pallor) indicate irreversible damage—do not wait for these to develop. 1, 2
Perform early fasciotomy when compartment pressure exceeds 30 mmHg or when differential pressure (diastolic blood pressure minus compartment pressure) is <30 mmHg. 1, 2
Pain Management
Use acetaminophen (500-1000 mg, maximum 4-6 grams daily) as first-line analgesic, as it avoids nephrotoxic effects. 1, 2
Reserve opioids for severe muscle pain unresponsive to acetaminophen. 1, 2
For opioid-naive patients with moderate to severe pain, start oral morphine at 20-40 mg. 1, 2
In patients with established acute kidney injury (eGFR <30 mL/min), use fentanyl or buprenorphine as the safest opioid choices. 1, 2
Provide round-the-clock dosing with rescue doses (10-15% of total daily dose) for breakthrough pain. 1
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
Consider discontinuation of RRT when urine output recovers adequately (>100 mL/day). 2
Additional Laboratory Monitoring
Obtain complete blood count with differential to evaluate for infection or systemic processes. 1
Check liver function tests (AST, ALT, alkaline phosphatase) as transaminitis commonly occurs due to muscle enzyme release. 1
Perform urinalysis looking for brown color, cloudiness, and positive blood without RBCs (indicating myoglobinuria). 1
For recurrent rhabdomyolysis, history of exercise intolerance, or family history of neuromuscular disorders, consider genetic testing including RYR1, CACNA1S, CPT2, PYGM, ACADM, AMPD1, and VLCAD genes. 1
Critical Pitfalls to Avoid
Do not delay fluid resuscitation—this is the most common error and is associated with significantly worse outcomes. 1, 2
Do not use inadequate fluid volumes that fail to achieve the target urine output of 300 mL/hour. 2
Do not miss compartment syndrome, particularly in traumatic or severe exertional cases, as this leads to irreversible muscle and nerve damage. 1, 2
Do not use the 1.5 mg/dL creatinine threshold as a trigger for intervention in trauma-related rhabdomyolysis—this threshold is specific to cirrhotic patients and not applicable here. 1
Recognize that CK levels peak 24-120 hours after the inciting event, not immediately—if clinical suspicion remains high, repeat CK measurement at 24 hours post-event. 1