Prognostic value, kinetics and effect of CVVHDF on serum of the myoglobin and creatine kinase in critically ill patients with rhabdomyolysis

Background: (I) To investigate the kinetics of the myoglobin and creatine kinase (CK) in rhabdomyolysis. Especially to describe those patients in whom art isolated increase in the myoglobin or the CK occurred at a later stage. (II) To evaluate the sensitivity of the myoglobin and the CK as prognostic tools for the development of Acute renal failure (ARF). (III) To investigate the effect of continuous venovenous haemodiafiltration (CVVHDF) on the myoglobin elimination in ARF. Patients and methods: Prospective and retrospective cohort study carried out in an ICU of a university hospital. A total of 47 critically ill patients with rhabdomyolysis and a plasma myoglobin > 5000 mu g l(-1) were admitted between July 1998 and July 2003. Results: (I) The myoglobin peaked 0.66 +/- 0.6 days before the CK. The elimination kinetics of the myoglobin was faster than for the CK. (II) Fifty percent developed ARE Mortality in the ARF patients was 52% compared to 14% in the non-ARF patients. The sensitivity and specificity of developing ARF were higher with the myoglobin in comparison to the CK. (III) In non-ARF, t1/2 CK was 25.5 h and t1/2 myoglobin was 17 h (13-23). In those with ARF treated with CVVHDF, t1/2 CK was 24.8 and t1/2 myoglobin was 21 h (17-29). Conclusion: (I) The myoglobin peaked earlier than the CK. (II) The myoglobin was a better prognostic tool than the CK. However, the myoglobin also has a wide interindividual range. (III) Though the myoglobin is eliminated in ultrafiltration t1/2 myoglobin, it was not faster in patients with ARF treated with CVVHDF compared to non-ARF patients.