Blood types
There are eight major blood types: A+, A-, B+, B-, O+, O-, AB+, and AB-. Type O blood is the most demanded by hospitals for two reasons. The first is that it is the most common, with around 45 percent of the U.S. population having this type of blood. The second reason is that O negative blood can be transfused for any blood type. People with O negative blood are therefore referred to as universal donors. Just seven percent of the U.S. population has O negative blood, with this type slightly more common among white people.Who donates blood?
In 2021, a survey of U.S. adults found that just 15 percent stated they had donated blood in the last 12 months. According to the most recent data from the CDC’s National Blood Collection and Utilization Survey (NBCUS), the largest survey of blood collection and utilization data in the United States, around 6.55 million people donated blood in 2021, with around 1.72 million of these people first-time donors. At that time, those aged 25 to 64 years accounted for 69 percent of donations, while those aged 16 to 18 accounted for four percent. In order to donate blood in the United States, each donor must complete a questionnaire, and each unit of blood is routinely screened to minimize the risk of transmitting disease. When an individual is deemed ineligible to donate blood because of health or safety concerns, it is known as a donor deferral. The most common reason for donor deferral in the United States is due to low hemoglobin/hematocrit.Blood transfusions
Every day, blood that has been donated is transfused to save lives. Blood transfusions are one of the most common medical procedures in the United States, with donated blood used in surgery, helping cancer patients, and treating those with traumatic injuries or chronic illnesses. In 2021, there were almost 10.8 million blood transfusions in the United States. The majority of blood transfusions take place in inpatient medical settings, followed by critical care, and outpatient and non-acute inpatient settings, such as outpatient dialysis, rehabilitation, and long-term care. Although most patients do not experience any side effects from blood transfusions, adverse reactions can occur. In 2021, there were around 45,142 blood transfusion-associated adverse reactions in the United States. The most common was fever or chills, known as febrile non-hemolytic transfusion reaction, followed by mild to moderate allergic reactions.
