L for adult women. The term hypochromia refers to RBC populations with MCH Anemia Associated with Blood Loss from Surgery Patients undergoing major surgery can experience considerable blood loss. This is especially true for patients undergoing elective orthopedic procedures such as primary hip or knee arthroplasty and spinal fusion. This blood loss can be especially difficult to manage in older patients, who comprise a large proportion of those requiring arthroplasty procedures. Because the marrow reserve is limited, anemia may result from hemorrhage associated with incision of a large blood vessel, erosion of an artery by lesions, or failure of normal hemostasis.
Immediate effects depend on the duration and volume of hemorrhage.
During and immediately after hemorrhage, the RBC count, Hb, and Hct may be deceptively high because of vasoconstriction. Within a few hours, however, tissue fluid enters the circulation, resulting in hemodilution and a drop in the RBC count proportional to the severity of bleeding. Plasma is replaced within 1 to 3 days, but a low concentration of RBCs remains. The RBC concentration usually returns to normal within 3 to 6 weeks if no further hemorrhage occurs. Recombinant Human Erythropoietin Human erythropoietin was first isolated in 1977.