Blood Transfusion | Patient Information | JAMA | JAMA Network
[Skip to Navigation]
Access to paid content on this site is currently suspended due to excessive activity being detected from your IP address Please contact the publisher to request reinstatement.
Citations 0
JAMA Patient Page
October 6, 2004

Blood Transfusion

JAMA. 2004;292(13):1646. doi:10.1001/jama.292.13.1646

Blood transfusion can be life-saving. Blood products include whole blood (blood with all of its components, rarely used now), packed red blood cells (blood cells that carry oxygen), platelets (cells in the blood that allow blood clots to form), plasma (the liquid portion of blood without cells), and concentrated clotting factors.

When packed red blood cells are transfused, an individual's blood count increases. This blood count is usually measured as the hemoglobin level. Hemoglobin is a protein that carries oxygen to the tissues and cells of the body. Normal hemoglobin levels are about 12 to 15 grams per 100 milliliters of blood for women and about 14 to 17 for men. Although individual circumstances can be different, anemia (low red blood cell count) requiring transfusion usually occurs when the hemoglobin is about 7. Medical research has shown that significant decreases in tissue oxygen delivery occur when the hemoglobin drops to that level. The October 6, 2004, issue of JAMA includes an article about blood transfusion in the setting of acute coronary syndrome (heart attack).