What is the treatment for a patient with suspected Rhabdomyolysis?

Treatment of Rhabdomyolysis

Immediately initiate aggressive intravenous fluid resuscitation with 0.9% normal saline at 1 liter per hour to prevent acute kidney injury and reduce mortality. 1

Immediate Fluid Resuscitation

Start IV fluids as soon as possible—delayed initiation significantly increases the risk of acute kidney injury. 2, 3

• Establish IV access immediately and begin 0.9% normal saline at 1000 mL/hour during the initial phase 1
• Target urine output of ≥300 mL/hour (approximately 3-5 mL/kg/hour for a 70 kg patient) to ensure adequate myoglobin clearance and prevent tubular precipitation 3
• Insert a bladder catheter to monitor hourly urine output unless urethral injury is suspected 1, 3
• Reduce infusion rate by 50% if initial resuscitation exceeds 2 hours to avoid volume overload 1

Fluid Volume Requirements Based on Severity

• Severe rhabdomyolysis (CK >15,000 IU/L): Administer >6L of IV fluids per day 2, 3
• Moderate rhabdomyolysis: Administer 3-6L of IV fluids per day 2, 3

Fluids to AVOID

Do not use potassium-containing fluids such as Lactated Ringer's solution, Hartmann's solution, or Plasmalyte A, as potassium levels can increase markedly after reperfusion even with intact renal function 1, 3

Avoid starch-based fluids due to their association with increased rates of acute kidney injury and bleeding 1, 3

Electrolyte Monitoring and Management

Monitor electrolytes (particularly potassium, calcium, phosphorus) every 6-12 hours in severe cases 2, 1

• Treat hyperkalemia emergently as it can precipitate life-threatening cardiac arrhythmias 2
• Perform repeated bioassessments of plasma myoglobin, CK, and potassium 2, 3
• Trend CK, creatinine, and electrolytes daily until CK is declining and renal function is stable 2

Medication Management

Immediately discontinue any causative agents:

• Statins and other prescription medications 2
• Supplements including red yeast rice containing lovastatin, creatine monohydrate, wormwood oil, licorice, and Hydroxycut 2, 1

Bicarbonate and Mannitol: NOT Routinely Recommended

Do not routinely use urinary alkalinization with bicarbonate—current evidence does not demonstrate benefit over aggressive fluid resuscitation with crystalloids alone 3

• Bicarbonate is only indicated for severe metabolic acidosis or life-threatening hyperkalemia, not for routine rhabdomyolysis management 3
• Large doses of bicarbonate can worsen hypocalcemia by decreasing free calcium levels 3

Do not routinely use mannitol—studies suggest little additional benefit compared to crystalloid resuscitation alone, and it is potentially nephrotoxic 3

• Mannitol may only benefit patients with markedly elevated CK (>30,000 U/L), though this benefit remains undefined 3
• Mannitol is contraindicated in patients with oligoanuria 3

Renal Replacement Therapy Indications

Initiate dialysis early for:

• Refractory hyperkalemia 1
• Severe metabolic acidosis 1
• Fluid overload despite conservative management 1, 3
• Persistently elevated CK levels after 4 days of adequate hydration 1

Intermittent hemodialysis is the preferred modality as it provides rapid clearance of potassium 3

Compartment Syndrome Management

Perform early fasciotomy when:

• Compartment pressure exceeds 30 mmHg 2, 1
• Differential pressure (diastolic BP – compartment pressure) is <30 mmHg 2, 1

Early signs include pain, tension, paresthesia, and paresis—late signs like pulselessness and pallor often indicate irreversible damage 2

Pain Management

Use acetaminophen as the preferred initial analgesic at 500-1000 mg (maximum 4-6 grams daily) to avoid nephrotoxic effects 2

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

Reserve opioids for severe pain unresponsive to acetaminophen:

• Oral morphine 20-40 mg for opioid-naive patients 2
• In patients with established AKI (eGFR <30 mL/min), use fentanyl or buprenorphine as the safest opioid choices 2

Duration of Treatment

Continue IV fluids until:

• CK levels decrease (typically <1,000 U/L) 1, 4
• Urine output remains adequate 1
• Electrolytes normalize 1
• Renal function stabilizes or improves 1

Critical Pitfalls to Avoid

Do not wait for creatinine elevation to trigger intervention—the 1.5 mg/dL creatinine threshold is specific to cirrhotic patients and not applicable to rhabdomyolysis 3

Do not use diuretics as primary treatment—they may increase the risk of acute kidney injury unless adequate volume resuscitation has first been achieved 3

Do not assume impact trauma alone explains CK elevation—while simple contusion can elevate CK, given the clinical context, assume true muscle breakdown until proven otherwise 2