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Blood Transfusions

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A blood transfusion is a fairly simple medical procedure. In a transfusion, a patient receives whole blood or one of its parts through an intravenous line, or IV. This is a tiny tube that is inserted into a vein using a small needle.

While patients are likely to feel a brief pinch of the needle, a blood transfusion is mostly painless. Still, because it involves a needle, kids might be anxious if they have to get one. So it helps to understand how a transfusion is done. That way, you can feel confident about what is happening and help put your child at ease.

About Blood Transfusions

Blood is like the body's transportation system. As blood circulates, it delivers oxygen and nutrients throughout the body. It also collects waste products and carries them to the organs responsible for making sure the wastes leave the body.

Whole blood is a mixture of cells and liquid, and each part has a specific job:

  • Red blood cells carry oxygen to the body's tissues and remove carbon dioxide.
  • White blood cells help defend the body against infection by producing antibodies, which help destroy foreign germs in the body.
  • Platelets, the smallest blood cells, help to clot the blood and control bleeding.
  • Plasma, the pale yellow liquid part of whole blood. It's a mixture of water, proteins, electrolytes, carbohydrates, cholesterol, hormones, and vitamins.

A blood transfusion can make up for a loss of blood or any part of the blood. Although whole blood can be transfused, it is rarely used. Instead, more specific parts of blood are transfused as needed. Red blood cells, the most commonly transfused part, are used to increase the blood's ability to carry oxygen and prevent tiredness and other complications.

Transfusions take 1 to 4 hours, depending on how much blood is given and the blood type. No special recovery time is needed.

Most transfusions are done in a hospital, but can be done elsewhere when necessary. In most cases, the blood comes from volunteer donors. The blood of the donor, which is carefully screened to ensure its safety, must be compatible with the blood type of the person receiving it.

There are four major blood types, each with a different chemical marker that's attached to a person's red blood cells. These markers determine if someone has type A blood, type B blood, type O blood, or type AB blood. Each blood type also can be positive (+) or negative (-).

Why Blood Transfusions Are Performed

The three main reasons why a child may need a blood transfusion are:

  1. Loss of blood during surgery or from an injury or an illness.
  2. An inability to make enough blood. Some illnesses and treatments can harm the bone marrow's ability to make blood (e.g., chemotherapy decreases production of new blood cells).
  3. To prevent complications from an existing blood or bleeding disorder, such as sickle cell disease, thalassemia, or anemia caused by kidney disease, hemophilia, or von Willebrand disease.

Where the Blood Comes From

Because there's no manmade substitute for blood, the blood supply used for transfusion must be donated. The three types of blood donation are:

  1. Autologous (ah-TOL-uh-gus) blood donation. Sometimes, when people know in advance that they are going to need a transfusion (for a planned surgery, for example), they may donate their own blood beforehand. There's no age requirement, but in general, kids don't donate their blood for their own use until they're over age 12.
  2. Directed donation. This is when a family member or friend with a compatible blood type donates blood specifically for use by a designated patient.
  3. Volunteer donation. Since there's no medical evidence that blood from directed donors is any safer than blood from volunteer donors, most patients receive blood donated through blood drives, which are often run by independent collection agencies like the American Red Cross. The minimum age for donating blood is 16 or 17 years old, depending on where a person lives.

Some people worry about getting diseases from infected blood, but the United States has one of the safest blood supplies in the world. Many organizations, including community blood banks and the federal government, work hard to make sure that the blood supply is safe.

The risk of getting a disease like HIV or hepatitis through a transfusion is extremely low in the United States today because of very stringent blood screening. Also, the needles and other equipment used are sterile, and are used only on one person and then thrown away in special containers.

Preparing for a Blood Transfusion

If your child needs a blood transfusion, the doctor will speak with you about the procedure. If you have questions, be sure to ask. When you feel comfortable with the information and your questions have been fully answered, you'll be asked to sign an informed consent form. This form states that you understand the procedure and its risks, and give your permission for your child to have the blood transfusion.

If the situation is not a life-threatening emergency, two tests will be done before the transfusion:

  1. Blood typing. To confirm your child's blood type, a nurse or technician will draw a sample from a vein in your child's arm using a sterile needle. (Except for the brief needle stick, this isn't painful and only takes a few minutes.) This blood is immediately labeled with your child's name, birth date, and medical record number, and an armband with matching information is made for your child to wear. The blood is then sent to the hospital's blood bank lab, where technicians test it for blood type.
  2. Cross-matching. Once typing is complete, a compatible donor blood is chosen. As a final check, a blood bank technologist will mix a small sample of your child's blood with a small sample of the donor blood to confirm they are compatible. If they clump together, the blood is not compatible. If the blood mixes smoothly, they are. Blood that is considered compatible is then labeled with your child's name, birth date, and medical record number and delivered to where your child will be receiving the transfusion.

Most transfusions are done in a hospital setting, often at a patient's bedside, or in the operating room, emergency room, or chemotherapy unit. They also can be done in an outpatient care clinic or even at home, if necessary.

As long as the transfusion is not being done during surgery, you can stay with your child, who will be awake. Your child can sit comfortably in a reclining chair or lie down on a bed, watch a movie, listen to music, or play quietly, and might be able to eat and drink, walk around a bit, and use the bathroom.

Starting an IV Line

A nurse will begin an intravenous line (IV). After the needle is inserted into an arm or hand, a small sample of blood is taken and sent to a lab to confirm the blood type. Once the results are in, a tiny plastic tube is left in the vein and attached to the IV tubing, which is then used to connect to the bag containing the blood.

Since puncturing the skin involves a small needle, starting an IV can cause a little bit of pain (kind of like a small pinch). To reduce discomfort, a nurse might put some numbing cream on your child's skin a half hour before inserting the needle.

Though the vein is typically in the arm or hand, it can be done in other places, if necessary, especially if conditions like severe dehydration or blood loss have made the veins harder to find. For example, babies often receive transfusions through veins in their foot or scalp.

Children who need many transfusions may require a central line (a tube inserted into a larger vein in the chest) or a PICC line (a longer tube inserted through a vein near the bend of the elbow). These lines allow easy access and also spare smaller veins the damage that can come from repeated punctures.

Most kids don't need any special medicines before or during a blood transfusion. However, if your child had a mild reaction during a previous transfusion, the doctor might give your child some medicine just before the procedure, either by mouth or through the IV.

Two nurses will read to each other the names and identification numbers on your child's armband and on the blood that came from the blood bank. The transfusion won't begin unless there is a match.

Transfusing the Blood

The blood bag is hung upside down from an IV pump that controls the speed of the flow.


The nurse will measure your child's blood pressure, body temperature, and pulse before, during, and after the transfusion. Your child also will be watched closely for any signs of an allergic or other type of reaction, including rash, fever, headache, or swelling.

After the transfusion, if your child is going home, the tiny plastic tube is removed from the vein and a bandage is placed over the area. The site may be slightly sore or tingly for a little while. Medicine may be given for any mild side effects, such as fever or headache. If your child is having surgery or is in the hospital, the IV line will stay in place.


In kids with anemia or those getting chemotherapy, the greatest benefit of a transfusion is increased blood flow to nourish the organs and improve oxygen levels in the body. This can keep them from feeling extreme tiredness and help give them enough energy for the activities of daily life. Benefits like this often are felt fairly quickly.

For patients with bleeding problems, transfusions with platelets or plasma can help to control or prevent bleeding complications.

Serious reactions to transfusions are rare. But as with any medical procedure, they have a few potential risks, which your doctor will review with you.

When your child is having any kind of procedure, it's understandable to be a little uneasy. But it helps to know that blood transfusions are common procedures and complications are rare. If you have any questions about transfusions, talk with your doctor.

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Note: All information is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor.

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