Blood (serum) myoglobin is a test that measures the amount of myoglobin in the blood.
Myoglobin is a protein in heart and skeletal muscles. When you exercise, your muscles use up any available oxygen. Myoglobin has oxygen attached to it, which provides extra oxygen for the muscles to keep at a high level of activity for a longer period of time.
When muscle is damaged, myoglobin is released into the bloodstream. The kidneys help remove myoglobin from the body into the urine. In large amounts, myoglobin can damage the kidneys.
There is very little risk involved with having your blood taken. Veins and arteries vary in size from one patient to another and from one side of the body to the other. Taking blood from some people may be more difficult than from others.
Other risks associated with having blood drawn are slight but may include:
Fainting or feeling light-headed
Hematoma (blood accumulating under the skin)
Infection (a slight risk any time the skin is broken)
David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine. Also reviewed by A.D.A.M. Health Solutions, Ebix, Inc., Editorial Team: David Zieve, MD, MHA, David R. Eltz, Stephanie Slon, and Nissi Wang.