Anemia is, in the simplest terms, a condition in which there is a reduction in the number of circulating red blood cells in the body. We often discuss this in relation to hemoglobin.
For men, anemia would indicate a hemoglobin level of less than 13 and in women a hemoglobin level of less than 12.
Previously undiagnosed anemia was identified in 5 to 75 percent of elective surgery patients in certain populations, and a national audit demonstrated that 35 percent of patients scheduled for joint replacement therapy have a hemoglobin level of less than 13 g/dL on preadmission testing.
At UPMC, it is estimated that 25 percent of all patients have low hemoglobin levels before their surgery.
In many cases, anemia will be diagnosed after a workup for fatigue or shortness of breath when labs demonstrate a low hemoglobin level.
Many patients, however, are symptom-free, and anemia may only come to light on screening or preoperative lab work.
When most people think of anemia, the first thing they think about is iron or B12 deficiency.
There are, however, many potential causes of anemia including:
In addition, anemia can result from chemotherapy or even certain malignancies. There also are rare genetic causes of anemia.
In most situations, anemia can be corrected with intervention preoperatively. Interventions, including B12, IV Iron infusions, and growth factors can be employed to achieve a safe hemoglobin count prior to surgery.
If the preoperative blood count is maximized, the need for transfusion support can be diminished.
The human body is quite capable of functioning safely at reduced blood levels, and therefore if the blood count preoperatively is near normal, a patient may be able to sustain significant blood loss during an operation without requiring any blood products.
The body will naturally produce more red cells in response to anemia, and in many cases can correct an anemia without transfusion. In cases where anemia is present preoperatively, the body may be unable to maintain a “safe” level of hemoglobin, and hence transfusion support would be necessary.