Most blood transfusions go very smoothly. Sometimes mild problems can occur. Very rarely, serious problems occur.
Some people have allergic reactions to the blood given during transfusions. This can happen even when the donated blood is the correct blood type.
Allergic reactions can be mild or severe. Symptoms may include:
A nurse or doctor will stop the transfusion at the first signs of an allergic reaction. The health care team will figure out the severity of the reaction, what treatments are needed, and whether they can safely restart the transfusion.
Some infectious agents, such as HIV, can survive in blood and infect the person receiving the blood transfusion. To keep blood safe, blood banks carefully screen donated blood.
The risk of catching a virus from a blood transfusion is low.
You may get a sudden fever during or within a day of your blood transfusion. This usually is your body's normal response to white blood cells in the donated blood. Over-the-counter fever medicine usually will treat the fever.
Some blood banks remove white blood cells from whole blood or different parts of the blood. This reduces the risk that you will have a reaction after the transfusion.
Getting many blood transfusions can cause too much iron to build up in your blood (iron overload). People who have a blood disorder like thalassemia, which requires multiple transfusions, are at risk for iron overload. Iron overload can damage your liver, heart, and other parts of your body.
If you have iron overload, you may need iron chelation (ke-LAY-shun) therapy. For this therapy, medicine is given through an injection or as a pill to remove the extra iron from your body.
Although it's unlikely, blood transfusions can damage your lungs, making it hard to breathe. This usually occurs within about 6 hours of the procedure.
Most patients recover. However, some patients who develop lung injuries die. These people usually were very ill before the transfusion.
Doctors aren't completely sure why blood transfusions damage the lungs. Antibodies (proteins) that are more likely to be found in the plasma of women who have been pregnant may disrupt the normal way that lung cells work. Because of this risk, hospitals are starting to use men's and women's plasma differently.
An acute immune hemolytic reaction is very serious, but also very rare. It occurs if the blood type you get during a transfusion doesn't match or work with your blood type. Your body attacks the new red blood cells, which then produce substances that harm your kidneys.
The symptoms include chills, fever, nausea, pain in the chest or back, and dark urine. Your doctor will stop the transfusion at the first sign of this reaction.
This is a much slower version of an acute immune hemolytic reaction. Your body destroys red blood cells so slowly that the problem can go unnoticed until your red blood cell level is very low.
Delayed hemolytic reactions are more common in patients who have had a previous transfusion than in those who haven't.
Graft-versus-host disease (GVHD) is a condition in which white blood cells in the new blood attack your tissues. GVHD usually is fatal. This condition affects people who have very weak immune systems.
Symptoms start within a month of the blood transfusion. They include fever, rash, and diarrhea. To protect against GVHD, donated blood can be treated so that the white blood cells can't cause GVHD.
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