More possible Risks

Transfusion-related acute lung injury

Transfusion-related acute lung injury (TRALI) is a rare, but very serious transfusion reaction. It can happen with any type of transfusion, but those that contain more plasma, such as fresh frozen plasma or platelets, seem more likely to cause it. It often starts within 1 to 2 hours of starting the transfusion, but can happen anytime up to 6 hours after a transfusion. There’s also a delayed TRALI syndrome, which can begin up to 72 hours after the transfusion is given.

The main symptom of TRALI is trouble breathing, which can become life-threatening. If TRALI is suspected during the transfusion, the transfusion should be stopped right away.

Doctors now believe that several factors are involved in this illness, and medicines don’t seem to help. Many of the patients who get TRALI have had recent surgery, trauma, cancer treatment, transfusions, or have an active infection. Most of the time, TRALI goes away within 2 or 3 days if breathing and blood pressure are supported, but even with support it is deadly in 5% to 10% of cases. TRALI is more likely to be fatal if the patient was already very ill before the transfusion. Most often a patient will need oxygen, fluids, and sometimes support with a breathing machine.

Delayed TRALI has a higher risk of death, with one expert finding a death rate as high as 40%. If a patient who has had TRALI needs red blood cells, doctors may try to prevent future problems by removing most of the plasma from the red blood cells using a diluted salt water solution. Researchers are working on other ways to reduce this risk with careful donor selection and testing.

Acute immune hemolytic reaction

An acute hemolytic (he-mo-LIT-ik) reaction is the most serious type of transfusion reaction, but it’s very rare. It happens when donor and patient blood types do not match. The patient’s antibodies attack the transfused red blood cells, causing them to break open (hemolyze) and release harmful substances into the bloodstream.

Patients may have chills, fever, chest and lower back pain, and nausea. The kidneys may be badly damaged, and dialysis may be needed. A hemolytic reaction can be deadly if the transfusion is not stopped as soon as the reaction starts.

Delayed hemolytic reaction

This type of reaction happens when the body slowly attacks antigens (other than ABO antigens) on the transfused blood cells. The blood cells are broken down days or weeks after the transfusion. There are usually no symptoms, but the transfused red blood cells are destroyed and the patient’s red blood cell count falls. In rare cases, the kidneys may be affected, and treatment may be needed.

People don’t usually have this type of reaction unless they have had transfusions in the past. Those who do have this reaction need special blood tests before any more blood can be transfused. Units of blood that do not have the antigen that the body is attacking must be used.