Afterward, there may be some throbbing . It is also used for regulation of body temperature, regulation of fluids, and acid-base equilibrium. Plasma contains various substances dissolved in the fluid. The cellular portion consists primarily of red blood cells, but also includes white blood cells and platelets . Because blood is used for multiple functions within the body, tests on the blood or its components may give valuable clues in the diagnosis of a multitude of medical conditions.
Normal results vary with the specific test.
The cost varies with the specific test. Veins and arteries vary in size from one patient to another and from one side of the body to the other. Obtaining a blood sample from some people may be more difficult than from others. The blood will be stored under tightly controlled refrigeration. This unit of blood has been typed, screened for disease, cross matched for blood type, and is now ready for infusion into the patient.