From the Guidelines
Rhabdomyolysis should be diagnosed and treated promptly with aggressive intravenous fluid administration, typically normal saline at 1-2 L/hour initially, to prevent kidney damage and reduce morbidity and mortality. The diagnosis of rhabdomyolysis is confirmed when creatine kinase (CK) levels are elevated, typically above 1,000 U/L, often accompanied by myoglobinuria, elevated creatinine, and electrolyte abnormalities 1. Treatment focuses on preventing kidney damage, with hydration being the cornerstone of therapy. The goal is to flush myoglobin from the kidneys and prevent acute kidney injury.
Key Components of Treatment
- Aggressive intravenous fluid administration, usually normal saline at 1-2 L/hour initially, then adjusted based on urine output targeting 200-300 mL/hour 1
- Monitoring and correction of electrolyte imbalances, particularly hyperkalemia, hypocalcemia, and hyperphosphatemia
- Consideration of urinary alkalinization with sodium bicarbonate in severe cases to reduce myoglobin toxicity, though this remains controversial 1
- Renal replacement therapy (dialysis) for patients with severe kidney injury, refractory hyperkalemia, or volume overload
Monitoring and Adjustment
- Close monitoring of kidney function, electrolytes, and CK levels is essential throughout treatment, with CK levels typically checked daily until declining 1
- Adjustment of fluid administration based on urine output and clinical response
- Identification and addressing of the underlying cause of rhabdomyolysis, whether it's medication-related, trauma, excessive exercise, or another condition 1
Evidence-Based Recommendations
The most recent and highest quality study 1 suggests that early and aggressive fluid resuscitation is crucial in preventing acute kidney injury and reducing the need for renal replacement therapy in patients with rhabdomyolysis. Additionally, the measurement of plasma myoglobin may be more sensitive and specific than CPKs in identifying the risk of acute kidney injury, which is correlated with increased mortality 1. Therefore, prompt diagnosis and treatment of rhabdomyolysis, with a focus on aggressive fluid administration and monitoring of kidney function and electrolytes, is essential to reduce morbidity and mortality.
From the Research
Diagnosis of Rhabdomyolysis
- Rhabdomyolysis is a clinical syndrome defined by muscle breakdown and subsequent release of intracellular contents 2
- The diagnosis is confirmed most reliably with the finding of elevated serum creatine kinase levels 2
- Presenting symptoms include tea-colored urine and muscle weakness or fatigue 2
- A high index of clinical suspicion is required to promptly recognize rhabdomyolysis, especially in the unconscious patient 2
Treatment Options for Rhabdomyolysis
- Early, aggressive resuscitation with either normal saline or lactated Ringer's solution to maintain an adequate urine output is the most important intervention in preventing the development of acute renal failure 2
- Aggressive intravenous fluid resuscitation (IVFR) decreases the incidence of acute renal failure (ARF) and need for dialysis in patients with rhabdomyolysis 3
- Immediate, aggressive intravenous volume expansion is indicated to prevent myoglobinuric renal failure 4
- Early vigorous fluid resuscitation with ≥12 l daily intravenous infusion of alkaline solution started at the scene of injury can stabilize the circulation and mobilize edema fluids sequestered in the injured muscles into the circulation, correct hyperkalemia and acidosis, and protect against the nephrotoxic effects of myoglobinemia and hyperuricosuria 5
- There is insufficient clinical evidence supporting the routine administration of diuretics and bicarbonate to protect against the development of acute renal failure 2
- Bicarbonate and mannitol administration do not improve the incidence of acute renal failure and need for dialysis in patients with rhabdomyolysis 3