Preventing renal failure in patients with rhabdomyolysis: do bicarbonate and mannitol make a difference?

BACKGROUND The combination of bicarbonate and mannitol (BIC/MAN) is commonly used to prevent renal failure (RF) in patients with rhabdomyolysis despite the absence of sufficient evidence validating its use. The purpose of this study was to determine whether BIC/ MAN is effective in preventing RF in patients with rhabdomyolysis caused by trauma. METHODS This study was a review of all adult trauma intensive care unit (ICU) admissions over 5 years (January 1997-September 2002). Creatine kinase (CK) levels were checked daily (abnormal,>520 U/L). RF was defined as a creatinine greater than 2.0 mg/dL. Patients received BIC/MAN on the basis of the surgeon's discretion. RESULTS Among 2,083 trauma ICU admissions, 85% had abnormal CK levels. Overall, RF occurred in 10% of trauma ICU patients. A CK level of 5,000 U/L was the lowest abnormal level associated with RF; 74 of 382 (19%) patients with CK greater than 5,000 U/L developed RF as compared with 143 of 1,701 (8%) patients with CK less than 5,000 U/L (p < 0.0001). Among patients with CK greater than 5,000 U/L, there was no difference in the rates of RF, dialysis, or mortality between those who received BIC/MAN and those who did not. Subanalysis of groups with various levels of CK still failed to show any benefit of BIC/MAN. CONCLUSION Abnormal CK levels are common among critically injured patients, and a CK level greater than 5,000 U/L is associated with RF. BIC/MAN does not prevent RF, dialysis, or mortality in patients with creatine kinase levels greater than 5,000 U/L. The standard of administering BIC/MAN to patients with post-traumatic rhabdomyolysis should be reevaluated.