Objective: Myoglobin kinetics of removal from the circulation were studied in patients following massive rhabdomyolysis, to see if myoglobin remains for long in the circulation in the anuric state and if myoglobin elimination was affected by therapeutic manipulation such as haemofiltration or haemodialysis.
Design: Randomised and controlled study.
Setting: Intensive care unit of a tertiary care teaching hospital.
Patients: 26 patients of rhabdomyolysis whose serum myoglobin exceeded more than 500 nmol/l. Thirteen patients developed acute renal failure and underwent treatment with blood purification (Group HD). The remaining 13 patients did not require treatment with blood purification (control subjects, Group non-HD).
Interventions: In patients of group HD, twelve were treated with haemofiltration and/or haemodialysis. One was treated with peritoneal dialysis. The patient of group non-HD were treated with fluid infusion alone.
Measurements and results: The serum concentrations of myoglobin were serially determined. The highest levels of myoglobin was 1641 +/- 484 nmol/l (mean +/- SEM) in the group non-HD and were 8957 +/- 2300 in the group HD. In the group non-HD, the blood myoglobin fell exponentially once myoglobin release into the circulation ceased. This was also noted in the group HD. The exponential decrease was observed even on the days when the patient passed little urine or treatment with blood purification was not performed.
Conclusion: In patients with massive myoglobinaemia, the blood myoglobin rapidly fell independent of renal function or any therapeutic manipulation. The results indicate that extrarenal factors played a major role in disposing circulating myoglobin in such patients.