From the Guidelines
The recommended initial fluid resuscitation rate for patients with rhabdomyolysis is 1.5 L/hour (or approximately 10-15 mL/kg/hour) of isotonic crystalloid solution, typically normal saline (0.9% NaCl). This recommendation is based on the most recent and highest quality study available, which suggests that aggressive initial hydration is crucial in preventing acute kidney injury in patients with rhabdomyolysis 1. The study highlights that volumes greater than 6L were required in patients with severe rhabdomyolysis to prevent acute kidney injury and the need for renal replacement therapy.
Key Considerations
- The initial fluid resuscitation rate should be continued until the clinical situation stabilizes and myoglobinuria clears, after which the rate can be adjusted to maintain a urine output of 200-300 mL/hour (or 1-2 mL/kg/hour) 1.
- Total daily fluid requirements often range from 6-12 liters depending on the severity of the condition.
- The goal is to maintain this high urine output for the first 24-48 hours to prevent acute kidney injury.
- Fluid therapy should be adjusted based on the patient's cardiovascular status, with careful monitoring for signs of fluid overload, especially in patients with heart or kidney disease.
Monitoring and Adjustments
- Serum creatine kinase levels, electrolytes, and kidney function should be monitored regularly during treatment to guide ongoing management 1.
- Urine alkalinization with sodium bicarbonate (to maintain urine pH > 6.5) may be considered in severe cases, though this practice remains somewhat controversial.
- The management of kidney injury built up after rhabdomyolysis has no specificity, and experts refer to the French recommendations for acute kidney injury in the perioperative period and intensive care units 1.
From the Research
Recommended Initial Fluid Resuscitation Rate
The recommended initial fluid resuscitation rate for patients with rhabdomyolysis varies, but the following points summarize the key findings:
- Early and aggressive fluid resuscitation is agreed on as the main intervention for preventing and treating acute kidney injury (AKI) 2, 3, 4, 5.
- The use of ≥12 l daily intravenous infusion of alkaline solution started at the scene of injury has been suggested to 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 3.
- A rate of approximately 400 ml/hour, with adjustments ranging between 200 and 1000 ml/hour, depending on severity and volume states, has been reported for intravenous fluid replacement 6.
- Normal saline is the most commonly reported treatment for decreasing CK levels and myoglobinuria following exertional rhabdomyolysis, and it may be combined with other compounds including sodium bicarbonate, sodium chloride, or potassium chloride 6.
Key Considerations
- The diagnosis of rhabdomyolysis is confirmed by elevated creatine kinase levels, but additional testing is needed to evaluate for potential causes, electrolyte abnormalities, and AKI 2, 4.
- Treatment is aimed at discontinuation of further skeletal muscle damage, prevention of acute renal failure, and rapid identification of potentially life-threatening complications 4.
- Hyperkalemia and compartment syndrome are additional complications of rhabdomyolysis that must be treated effectively 4, 5.