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Health Information For Parents
Blood transfusions are a lifesaving treatment for many Americans. Blood transfusions are needed for many reasons, including surgery, after accidents, and for patients with
illnesses and cancer.
Blood cannot be artificially made, so doctors rely on volunteer donations. To keep the blood supply safe, every donation is tested for blood type and checked for infectious diseases.
All blood contains the same basic components:
But not everyone has the same blood type.
Categorizing blood according to type helps prevent reactions when someone gets a blood transfusion. Red blood cells have markers on their surface that characterize the cell type. These markers (also called antigens) are proteins and sugars that our bodies use to identify the blood cells as belonging in us.
The two main blood groups are ABO and Rh.
The ABO blood system has four main types:
Blood is further classified as being either “Rh positive” (meaning it has Rh factor) or “Rh negative” (without Rh factor).
So, there are eight possible blood types:
Having any of these markers (or none of them) doesn’t make a person’s blood any healthier or stronger. It’s just a genetic difference, like having green eyes instead of blue or straight hair instead of curly.
The immune system is the body’s protection against invaders. It can identify antigens as self or nonself. To get a blood transfusion safely, a person’s immune system must recognize the donor cells as a match to his or her own cells. If a match isn’t recognized, the cells are rejected.
The immune system makes proteins called antibodies that act as protectors if foreign cells enter the body. Depending on which blood type a person has, the immune system will make antibodies to react against other blood types.
If a patient gets the wrong blood type, the antibodies immediately set out to destroy the invading cells. This aggressive, whole-body response can give someone a fever, chills, and low blood pressure. It can even cause vital body systems — like breathing or the kidneys — to fail.
Here’s an example of how the blood type-antibody process works:
In the same way, if you have the B marker, your body makes A antibodies. So as a person with type B blood, you could get a transfusion from someone with B or O blood, but not A or AB.
Things are a little different for people with type AB or type O blood:
But if you have type O blood, your red blood cells have neither A or B markers. So:
Blood transfusions are one of the most frequent lifesaving procedures hospitals do. Every 2 seconds someone needs a blood transfusion. So there’s always a need for blood donors. One blood donation can save up to three lives.
Here are the basics about the life-sustaining fluid called blood.
Find out about the mysterious, life-sustaining fluid called blood.
About 5 million people a year get blood transfusions in the United States. This article explains why people need them and who donates the blood used.
Blood might look the same and do the same job, but tiny cell markers mean one person’s body can reject another person’s blood. Find out how blood types work in this article for teens.
Should you bank your newborn’s cord blood? This article can help you decide.
There’s a 97% chance that someone you know will need a blood transfusion. Blood donors â especially donors with certain blood types â are always in demand. Find out what’s involved in this article for teens.
If you just found out you’re pregnant, one of the first tests you should expect is a blood-type test. This basic test determines your blood type and Rh factor, which may play an important role in your baby’s health.
Find out what the experts have to say.
What does it mean when a kid has anemia? Learn about anemia, why kids get it, and how it’s treated in our article for kids.
Stem cells can develop into cells with different skills, so they’re useful in treating diseases like cancer.
Stay well and have a good time over the holidays – even if everyone else is falling apart. Our 5 tips will help boost your body’s defenses.
Note: All information is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor.
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