How to manage a patient with rhabdomyolysis and stagnant creatine kinase (CK) levels?

Management of Rhabdomyolysis with Stagnant Creatine Kinase Levels

For a patient with rhabdomyolysis whose CK has decreased from 69,000 to 5,900 but has remained stagnant for 3 weeks, aggressive hydration therapy should be continued or intensified with isotonic crystalloids to achieve a urine output of at least 200-300 mL/hour until CK levels begin to decrease again.

Initial Assessment and Management

• Evaluate for ongoing muscle injury that may be contributing to persistent CK elevation:

  • Medication review for potential myotoxic drugs
  • Assessment for compartment syndrome
  • Evaluation for underlying metabolic or inflammatory myopathies
  • Check for electrolyte abnormalities (particularly potassium, calcium, phosphorus)

• Intensify fluid management:

  • Use isotonic crystalloids (0.9% saline) rather than colloids 1
  • Target urine output of 200-300 mL/hour
  • Monitor for signs of volume overload (pulmonary edema, peripheral edema)
  • Consider adding loop diuretics if the patient has residual kidney function to reduce ultrafiltration requirements 2

Renal Protection Strategies

• Monitor renal function closely:

  • Daily BUN, creatinine, and electrolytes
  • Urine output monitoring
  • Consider 24-hour urine collection to assess residual kidney function every 3-4 months 1

• Avoid nephrotoxic agents:

  • NSAIDs
  • Aminoglycosides
  • Radiocontrast agents
  • Other potentially nephrotoxic medications 1, 2

• Consider ACE inhibitors or ARBs for kidney protection in normotensive patients with residual kidney function 1

Dialysis Considerations

If the patient has developed acute kidney injury requiring dialysis:

• Preserve residual kidney function:

  • Avoid episodes of intravascular volume depletion during hemodialysis 1
  • Maintain hemodynamic stability during dialysis sessions 1
  • Consider strategies to minimize hypotension: maintain target hematocrit, reduce dialysate temperature, increase dialysate sodium concentration 1, 2

• Optimize dialysis prescription:

  • For patients with residual kidney function (urine Kt/Vurea > 0.1/wk), total solute clearance should be measured within first month and every 6 months thereafter 1
  • For patients without residual kidney function, peritoneal Kt/Vurea should be at least 1.8/wk 1

Monitoring and Follow-up

• Continue monitoring CK levels every 2-3 days until downward trend resumes

• Monitor electrolytes closely, particularly:

  • Potassium (risk of hyperkalemia)
  • Calcium (risk of hypocalcemia)
  • Phosphorus (risk of hyperphosphatemia)

• Assess for complications of prolonged rhabdomyolysis:

  • Compartment syndrome
  • Disseminated intravascular coagulation
  • Cardiac arrhythmias from electrolyte disturbances 3, 4

Special Considerations

• If CK remains persistently elevated despite adequate hydration, consider additional diagnostic workup:

  • Muscle biopsy to rule out underlying myopathy
  • Genetic testing for metabolic myopathies
  • Evaluation for autoimmune myositis

• For patients with extremely high CK levels (>16,000 IU/L), the risk of acute renal failure is significantly increased 4

  • More aggressive hydration and closer monitoring may be warranted
  • Early consideration of renal replacement therapy if signs of renal failure develop 5

Pitfalls to Avoid

• Don't assume stagnant CK levels are benign - continued muscle injury may be occurring
• Don't underestimate fluid requirements - inadequate hydration is a common cause of persistent CK elevation
• Don't rely solely on CK levels - clinical assessment of muscle pain, weakness, and urine color remains important
• Don't discontinue monitoring once CK levels plateau - continued surveillance is necessary until normal levels are achieved
• Don't neglect residual kidney function - preservation is critical for long-term outcomes 1