In the ICU Patient Anemia is a common clinical problem in the critically ill that results in a large blood transfusion requirement. RBCs carry oxygen from the lungs to tissues throughout the body. All cells require oxygen to function. Once RBCs become filled with hemoglobin they enter the bloodstream as erythrocytes.
Healthy hemoglobin holds the oxygen molecules with a precise degree of force.
If it binds oxygen molecules in the lungs too loosely, it cannot hold onto them and carry them away. If it binds them too tightly, it cannot release them to tissues. If the kidneys fail to produce adequate EPO, anemia develops. O. Whether or not the type is positive or negative depends whether the Rh factor is present on the person's red blood cells. Despite the many regulations in place to assure the safety of blood supplies, transfusions are not risk free.