- What Is It
Although the blood type O+ can donate blood to all positive blood types (A+, B+, AB+, and O+), it is not a universal donor. Blood type O- is the universal blood donor, meaning that people with this blood type can donate blood to all other types with a lower risk of causing serious reactions.
What is a blood group?
Blood groups are an important categorization when it comes to many medical decisions.
The presence or absence of specific antigens on the surface of the red blood cells—and corresponding antibodies in the plasma—determines blood type.
What are antigens?
Antigens are proteins and polysaccharides that reside on the surface of red blood cells. Depending on the blood group system, these antigens could be carbohydrates, glycoproteins, or glycolipids.
The A antigen is found exclusively in the A blood type, whereas the B antigen is found only in the B blood type. Both A and B antigens are present in the AB blood type. Neither A nor B antigen is present in the O blood type.
If blood antigens are unfamiliar to the body, they can cause an immune reaction, which means a mismatch of blood can clump dangerously inside the veins.
What are antibodies?
Antibodies are disease-fighting proteins found in the plasma that are necessary for immunological responses.
Anti-B antibodies are found in people with blood type A, and anti-A antibodies are found in those with blood type B. Antibodies A and B cause an immune response against the opposite antigens respectively, thus making compatibility necessary.
What are the different classifications of blood groups?
The ABO and Rh-positive or Rh-negative blood type classification is used to classify blood groups.
A, B, AB, and O are the four blood types in the ABO system, determined by the presence or absence of the antigens A and B on the surface of red blood cells.
- Type-A: Contains only the A antigen
- Type-B: Contains only the B antigen
- Type-AB: Contains both A and B antigens
- Type-O: Does not contain either A or B antigens. Because there are no antigens present, an individual with an ABO blood type can receive type-O blood.
Blood can be Rh-positive or Rh-negative based on the presence or absence of the rhesus protein on the surface of red blood cells. Rh-positive indicates the presence of the protein, while Rh-negative indicates the absence of the protein.
A separate set of genes determines Rh blood type from the ones that influence the ABO blood type, one inherited from each parent. People with Rh-negative blood will have a strong immune reaction if Rh-positive blood enters their blood. Thus, it is important to identify a person’s blood type before transfusion.
With the Rh factor in mind, each person can be one of the following 8 blood groups:
- A RhD positive (A+)
- A RhD negative (A-)
- B RhD positive (B+)
- B RhD negative (B-)
- RhD positive (O+)
- RhD negative (O-)
- AB RhD positive (AB+)
- AB RhD negative (AB-)
How does blood type play a role in pregnancy?
If the mother has RhD-negative blood, but the fetus has RhD-positive blood, it might lead to difficulties if not properly managed.
During delivery, the blood of the mother and the infant may interact. If this happens, the mother’s body may react to the Rh protein as a foreign material and start producing antibodies against it. This can lead to complications, including miscarriage.
What is the compatibility of different blood types?
- Blood type O- is compatible with all blood groups. A person with blood type O+ can give blood to anybody with blood groups A+, B+, AB+, or O+; however, as a recipient it is only compatible with the O+ blood group.
- As a donor, the AB+ blood group is only compatible with the AB+ blood group, but as a recipient, it is compatible with all blood groups.
- As donors, blood groups A and B are compatible with blood groups A, AB and B, AB, respectively, and as a recipient, it is compatible with blood groups A, O and B, O, respectively.
Why is it important to know your blood type?
You should know your blood group for the following reasons:
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Health Solutions From Our Sponsors
Mitra R, Mishra N, Rath GP. Blood groups systems. Indian J Anaesth. 2014;58(5):524-528. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4260296/
Stanford Blood Center. Blood Types. https://stanfordbloodcenter.org/donate-blood/blood-donation-facts/blood-types/
The Royal Children's Hospital Melbourne. Blood Groups and Compatibilities. https://www.rch.org.au/bloodtrans/about_blood_products/Blood_Groups_and_Compatibilities/
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Common Medical Abbreviations & Terms
Doctors, pharmacists, and other health-care professionals use abbreviations, acronyms, and other terminology for instructions and information in regard to a patient's health condition, prescription drugs they are to take, or medical procedures that have been ordered. There is no approved this list of common medical abbreviations, acronyms, and terminology used by doctors and other health- care professionals. You can use this list of medical abbreviations and acronyms written by our doctors the next time you can't understand what is on your prescription package, blood test results, or medical procedure orders. Examples include:
- ANED: Alive no evidence of disease. The patient arrived in the ER alive with no evidence of disease.
- ARF: Acute renal (kidney) failure
- cap: Capsule.
- CPAP: Continuous positive airway pressure. A treatment for sleep apnea.
- DJD: Degenerative joint disease. Another term for osteoarthritis.
- DM: Diabetes mellitus. Type 1 and type 2 diabetes
- HA: Headache
- IBD: Inflammatory bowel disease. A name for two disorders of the gastrointestinal (BI) tract, Crohn's disease and ulcerative colitis
- JT: Joint
- N/V: Nausea or vomiting.
- p.o.: By mouth. From the Latin terminology per os.
- q.i.d.: Four times daily. As in taking a medicine four times daily.
- RA: Rheumatoid arthritis
- SOB: Shortness of breath.
- T: Temperature. Temperature is recorded as part of the physical examination. It is one of the "vital signs."
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How Many Pints of Blood Are There in the Human Body?The average human adult has about 8-10 pints of blood in the body, which is 8% of total body weight. A pint of blood is equivalent to 473.18 mL.
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Liver Blood TestsAn initial step in detecting liver damage is a simple blood test to determine the presence of certain liver enzymes in the blood. Under normal circumstances, these enzymes reside within the cells of the liver. But when the liver is injured, these enzymes are spilled into the blood stream, and can lead to diseases like fatty liver, type 2 diabetes, obesity, and hepatitis. Several medications also can increase liver enzyme test results.
What Are the 3 Rarest Blood Types?The red blood cells or RBCs present in the blood carry certain molecules, called antigens, on their surface that determine what blood group you have. The antigens depend on the genes you inherit from your parents. These antigens may be grouped in various categories to form a system for blood typing called the ABO system. The EldonCard blood type test kit uses the basic forward antibody technique of blood hematology for quick and simple determination of your blood type.
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