Blood and platelet transfusion is the process of transferring
blood or blood-based products, such as red blood cells, plasma,
or platelets, from one person into the circulatory system of
another. There are several different components of the blood
that can be transfused into an adult. Red blood cells are the
most common type of blood product transfusion. Human blood is
made of a fluid called plasma that carries red and white blood
cells and platelets. Each part of blood has special functions
and can be separated from each other. The bone marrow is the
soft, spongy material in the center of the bones that produces
about 95 percent of the body's blood cells. Platelets help
control bleeding by making clots in blood vessels opened by
injury or surgery. Many medical treatments, including treatments
for cancer patients, organ or bone marrow transplant patients,
victims of traumatic injury, and patients undergoing open heart
surgery require platelet transfusions. The body may not be able
to make enough platelets bec