LAB TEST
RBC count
An RBC count is a blood test that measures how many red blood cells (RBCs) you have. RBCs contain hemoglobin , a protein which carries oxygen. How much oxygen your body tissues get depends on how many RBCs you have and how well they work.
How the Test is Performed
A blood sample is needed.
How to Prepare for the Test
No special preparation is necessary.
How the Test will Feel
When the needle is inserted to draw blood, some people feel moderate pain. Others feel only a prick or stinging. Afterward, there may be some throbbing or a slight bruise. This soon goes away.
Why the Test is Performed
The RBC count is almost always part of a complete blood count ( CBC ) test. The test can help diagnose different kinds of anemia (low number of RBCs) and other conditions affecting red blood cells. Other conditions that may require an RBC count are: Bone marrow disorder in which the marrow is replaced by scar tissue…
Normal Results
Normal RBC ranges are: Male: 4.7 to 6.1 million cells per microliter (cells/mcL) Female: 4.2 to 5.4 million cells/mcL The ranges above are common measurements for results of these tests. Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or test different samples.…
What Abnormal Results Mean
Higher than normal numbers of RBCs may be due to: Bone marrow disease that causes abnormal increase in RBCs ( polycythemia vera ) Cigarette smoking Dehydration (for example, from severe diarrhea) Failure of the right side of the heart ( cor pulmonale ) Kidney tumor (renal cell carcinoma) Low blood oxygen level…
Risks
There is little risk involved with having your blood taken. Veins and arteries vary in size from one person to another and from one side of the body to the other. Taking blood from some people may be more difficult than from others. Other risks associated with having blood drawn are slight, but may include: Excessive…
References
Gallagher PG. Hemolytic anemias: red blood cell membrane and metabolic defects. In: Goldman L, Cooney KA, eds. Goldman-Cecil Medicine . 27th ed. Philadelphia, PA: Elsevier; 2024:chap 147. Kliegman RM, St. Geme JW, Blum NJ, Shah SS, Tasker RC, Wilson KM. Blood disorders. In: Kliegman RM, St. Geme JW, Blum NJ, et al,…
This is a summary. Read the full article at www.ucsfbenioffchildrens.org (reviewed 11/03/2024).
This page is general information and is not medical advice. It does not replace a registered doctor, and it is not a prescription or a recommendation to use any medicine or test. Prices are listed prices and may change. Always follow the advice of your doctor or pharmacist.