February 7, 2011 by dailybolusoflr
Patients with rhabdomyolysis are at risk for developing renal failure. The primary treatment modality aimed at reducing the risk of renal failure is intravenous hydration with normal saline. Average rates are typically twice maintenance to start but should focus on maintaining a urine output of at least 3cc/kg/hour (this is where you will hear the standard 200cc/h which is based on a typical 70kg person)
Mannitol and sodium bicarbonate can both be used as adjuvant treatments, but have not been proven to be effective in any controlled studies.
Mannitol increases urine flow via its diuretic mechanism, acts as a volume expander by drawing fluid out of interstitial spaces and may convert oliguric renal failure to non-oliguric renal failure, which has a better prognosis.
Sodium bicarbonate is used to alkalinize the urine, which may increase the solubility of myoglobin and increase its clearance. The goal is to keep urine pH greater than 6.5.
Loop diuretics, such as furosemide, can acidify the urine, which enhances precipitation of myoglobin and may decrease its clearance.
Renal failure, which is a late complication of rhabdomyolysis, typically develops approximately 24-48 hours after the inciting event.
Etiologies of rhabdomyolysis can include crush injuries, exertion, hyperthermia, drugs or toxins, electrocution injuries and infections.
Linda Regan, MD FACEP
Program Director, Emergency Medicine Residency
Johns Hopkins Medical Institutions