Complete Blood Count (CBC)

What Is A Complete Blood Count (CBC)

A CBC or complete blood count is routinely ordered in doctor’s offices, emergency rooms, and at annual checkups. It is a comprehensive test that calculates the cellular elements of the blood. While it measures many things one of the most important aspects of the lab test is the measure of the white and red blood cell counts, as well as the number of platelets present. This gives a physician a great deal of information allowing him/her to determine the internal workings of the body. The CBC is typically ordered with a Chemistry Panel to provide a more complete picture of a person’s health status.

When A CBC Blood Test Is Ordered

A CBC is a common laboratory blood test that is ordered when infection or disease is suspected, but also used for annual checkups. A CBC is also typically ordered if a patient complains of weakness, fatigue, or bruising. It gives a physician a good indication of the blood levels and if the body is operating as it should.
A CBC specifically measures the concentration and quality of cells in a person’s blood, especially white blood cells, red blood cells, and platelets. Some of the most common uses of the CBC blood tests are for the diagnosis of infection, inflammation, bruising or bleeding. Abnormally high or low counts of these cells may indicate conditions such as infection, anemia and many others.

More About CBC Blood Testing

To conduct the blood test the laboratory requires only a small amount of blood, between one and two teaspoons. The blood is drawn from the vein of the patient and transferred by a special vacuum sealed vial. Once in the lab, testing begins and will return a wide range of counts, however the following are the most well known:
• White blood count measures the amount of white blood cells and help a physician determine infection, as well as other medical conditions. The normal range varies from 4300 to 10,800 cmm. A high count can signify an infection.
• Red blood count is the number of red blood cells and the normal range is from 4.2 to 5.9 cmm.
• Hematocrit is the ratio of white to red blood cells – the normal ratio is 45% to 52% for men and 37% to 48% for women.
• Hemoglobin is the measure of the protein within the cell that carries oxygen – the normal range is 13 to 18 grams for men and 12 to 16 for women.
• Platelet count is important in the clotting of the blood – the normal range is 150,000 to 400,000 cmm