Evaluation of myoglobin clearance during continuous hemofiltration in a swine model of acute renal failure

Rhabdomyolysis is characterized by extensive damage of striated muscle, while the major complication of this disease is the development of acute myoglobinuric renal failure. Although first described more than five decades ago very little has changed with regard to the management of this entity as conventional hemodialysis has not been shown to effect myoglobin elimination. However, continuous arteriovenous hemofiltration (CAVH) offers an alternative to conventional hemodialysis as this procedure is more effective particularly for removing larger molecular weight substances such as myoglobin. We studied the effect of CAVH on myoglobin clearance in an animal model of acute myoglobinuric renal failure. Swine (n=6) were given 4 grams of equine myoglobin intravenously and underwent the CAVH procedure for six hours each. Once the filtering process was initiated there was a rapid and sustained production of ultrafiltrate. The clearance of myoglobin via the hemofilter was 2.05+/-1.48 L/day. The amount of myoglobin excreted in the ultrafiltrate over the six hour filtering period was 410+/-234 mg which accounts for 10.27+/-5.85 percent of the administered dose. Based on these findings, it appears that the hemofiltration system is a viable option for the removal of myoglobin from the systemic circulation.