The term comes from the time when hematocrit was the only method of measurement . Today, anemia is defined as a lower than normal hemoglobin concentration .
Cardiac hyperactivity causes palpitations , tachycardia and heart murmurs .
Other symptoms range from weakness, fatigue, and exercise intolerance or even dyspnea at rest . A pallor is the result of vasoconstriction which reroutes the blood to the oxygen dependent organs. The various forms of anemia differ quite a bit from each other, particularly in the peripheral blood film. A diagnosis can often be established at this stage. However, this must still be confirmed by specific supplementary tests.