When should rhabdomyolysis be considered in a patient?

From the Guidelines

Rhabdomyolysis should be considered in patients with severe limb trauma when CPK levels exceed five times normal, approximately 1000 IU/L, as indicated by recent guidelines 1. When evaluating patients for rhabdomyolysis, it is essential to consider the clinical context, including symptoms such as muscle pain, weakness, and dark urine. However, these symptoms may not always be present simultaneously.

• Key risk factors for rhabdomyolysis include trauma, crush injuries, prolonged immobilization, excessive exercise, seizures, or recent use of certain medications like statins, antipsychotics, or illicit drugs.
• Laboratory findings suggestive of rhabdomyolysis include markedly elevated creatine kinase (CK) levels, elevated serum creatinine, hyperkalemia, hypocalcemia, hyperphosphatemia, and metabolic acidosis, as well as myoglobinuria indicated by a positive urine dipstick for blood without red blood cells on microscopy 1. Early recognition and intervention with aggressive IV fluid resuscitation are critical to prevent acute kidney injury, a major complication of rhabdomyolysis 1.
• The goal of treatment is to prevent further muscle breakdown and support renal function, with isotonic saline administered at 1-2 L/hour initially, then adjusted based on clinical response. The pathophysiology of rhabdomyolysis involves muscle cell breakdown, releasing intracellular contents, particularly myoglobin, which can precipitate in renal tubules, causing obstruction and direct toxicity to kidney cells 1.

From the Research

Symptoms of Rhabdomyolysis

• Muscle pain and weakness
• Dark urine, which may be red-to-brown in color due to the presence of myoglobin (myoglobinuria) 2, 3, 4
• Elevated creatine kinase (CK) levels, which can indicate muscle damage 2, 3, 4, 5, 6

When to Consider Rhabdomyolysis

• In patients with a history of intense physical exercise, trauma, or other potential causes of muscle damage 2, 3, 4, 5, 6
• In patients with symptoms such as muscle pain, weakness, and dark urine, especially if these symptoms occur after intense physical activity or other potential causes of muscle damage 2, 3, 4, 5, 6
• In patients with elevated CK levels, which can indicate muscle damage 2, 3, 4, 5, 6

Importance of Early Diagnosis and Treatment

• Early diagnosis and treatment of rhabdomyolysis are crucial to prevent complications such as acute renal failure and electrolyte abnormalities 2, 3, 4, 5, 6
• Aggressive hydration with intravenous normal saline infusion is a key component of treatment to avoid complications 4, 6