CBC

A CBC is the oldest blood analysis and currently the most commonly performed blood test.

It consists of a combination of tests which analyze the ceIlular make up of the blood. Some specific analyses of the CBC are as follows:

Hematocrit

The hematocrit represents the percentage of the blood volume which is comprised by red blood cells. If forty percent of the blood consists of red blood cells then the hematocrit is 40 volumes percent. A low hematocrit is a sign of anemia. Such anemia may be from nutritional factors, blood loss (bleeding) or other disease processes.

Hemoglobin

Hemoglobin makes up about 1/3 of all red blood cells. As such, it is directly proportional to the hematocrit. Hemoglobin is the chemical which allows blood to carry oxygen from the lungs. Iron is important in the chemical structure of hemoglobin. A low hemoglobin also represents anemia.

White Blood Count

White blood cells are a normal component of blood. Their primary function is as a defense against infections. An elevated white blood cell count may be a sign of infection. Some viral infections may lower the white blood count. There are 5 different types of white blood cells. Increases or decreases in these cells may indicate particular medical conditions.

Platelets

Blood platelets are a component of blood which is important in blood clotting (to stop bleeding). Platelets act by "sticking" to each other and "clotting" the bleeding site. Aspirin affects the clotting of blood by decreasing the effectiveness of platelets.