Blood donation
A blood donation occurs when a person voluntarily has blood drawn and used for transfusions and/or made into blood products and biopharmaceutical medications by a process called fractionation. A donation may be of whole blood, or of specific components directly. Blood banks often participate in the collection process as well as the procedures that follow it.
In the developed world, most blood donors are unpaid volunteers who donate blood for a community supply. In some countries, established supplies are limited and donors usually give blood when family or friends need a transfusion. Many donors donate for several reasons, such as a form of charity, general awareness regarding the demand for blood, increased confidence in oneself, helping a personal friend or relative, and social pressure. Despite the many reasons that people donate, not enough potential donors actively donate. However, this is reversed during disasters when blood donations increase, often creating an excess supply that will have to be later discarded. In countries that allow paid donation some people are paid, and in some cases there are incentives other than money such as paid time off from work. People can also have blood drawn for their own future use. Donating is relatively safe, but some donors have bruising where the needle is inserted or may feel faint.
Potential donors are evaluated for anything that might make their blood unsafe to use. The screening includes testing for diseases that can be transmitted by a blood transfusion, including HIV and viral hepatitis. The donor must also answer questions about medical history and take a short physical examination to make sure the donation is not hazardous to their health. How often a donor can donate varies from days to months based on what component they donate and the laws of the country where the donation takes place. For example, in the United States, donors must wait 56 days between [|whole-blood donations] but only seven days between platelet apheresis donations and twice per seven-day period in plasmapheresis.
The amount of blood drawn and the methods vary. The collection can be done manually or with automated equipment that takes only specific components of the blood. Most of the components of blood used for transfusions have a short shelf life, and maintaining a constant supply is a persistent problem. This has led to some increased interest in autotransfusion, whereby a patient's blood is salvaged during surgery for continuous reinfusion—or alternatively, is self-donated prior to when it will be needed. Generally, the notion of donation does not refer to giving to one's self, though in this context it has become somewhat acceptably idiomatic.
History
The first non-direct transfusion was performed on March 27, 1914, by the Belgian doctor Albert Hustin, though this was a diluted solution of blood. The Argentine doctor Luis Agote used a much less diluted solution in November of the same year. Both used sodium citrate as an anticoagulant.The world's first blood donor service was established in 1921 by the secretary of the British Red Cross, Percy Lane Oliver. Volunteers were subjected to a series of physical tests to establish their blood group. The London Blood Transfusion Service was free of charge and expanded rapidly. By 1925, it was providing services for almost 500 patients and it was incorporated into the structure of the British Red Cross in 1926. Similar systems were established in other cities including Sheffield, Manchester and Norwich, and the service's work began to attract international attention. Similar services were established in France, Germany, Austria, Belgium, Australia and Japan.
In 1937 Bernard Fantus, director of therapeutics at the Cook County Hospital in Chicago, established one of the first hospital blood banks in the United States. In creating a hospital laboratory that preserved, refrigerated and stored donor blood, Fantus originated the term "blood bank". Within a few years, hospital and community blood banks were established across the United States.
Types of donation
Blood donations are divided into groups based on who will receive the collected blood. An allogeneic donation is when a donor gives blood for storage at a blood bank for transfusion to an unknown recipient. A directed donation is when a person, often a family member, donates blood for transfusion to a specific individual. Directed donations are relatively rare when an established supply exists. A replacement donor donation is a hybrid of the two and is common in developing countries. In this case, a friend or family member of the recipient donates blood to replace the stored blood used in a transfusion, ensuring a consistent supply. When a person has blood stored that will be transfused back to the donor at a later date, usually after surgery, that is called an autologous donation. Blood that is used to make medications can be made from allogeneic donations or from donations exclusively used for manufacturing.Sometimes there are specific reasons for preferring one form or the other. Allogeneic donations have a lower risk of some complications than blood from a family member. Neonatal alloimmune thrombocytopenia may require a transfusion from the mother's own platelets. Autologous donations may be preferred for someone with a rare blood type for a planned surgery.
Blood is sometimes collected using similar methods for therapeutic phlebotomy, similar to the ancient practice of bloodletting, which is used to treat conditions such as hereditary hemochromatosis or polycythemia vera. This blood is sometimes treated as a blood donation, but may be immediately discarded if it cannot be used for transfusion or further manufacturing.
The actual process varies according to the laws of the country, and recommendations to donors vary according to the collecting organization. The World Health Organization gives recommendations for blood donation policies, but in developing countries many of these are not followed. For example, the recommended testing requires laboratory facilities, trained staff, and specialized reagents, all of which may be unavailable or unaffordable in developing countries.
A blood drive or a blood donor session is an event in which donors come to donate allogeneic blood. These can occur at a blood bank, but they are often set up at a location in the community, such as a shopping center, workplace, school, or house of worship.
Screening
Donors are typically required to give consent for the process, and meet a certain criteria such as weight and hemoglobin levels, and this requirement means minors cannot donate without permission from a parent or guardian. In some countries, answers are associated with the donor's blood, but not name, to provide anonymity; in others, such as the United States, names are kept to create lists of ineligible donors. If a potential donor does not meet these criteria, they are 'deferred'. This term is used because many donors who are ineligible may be allowed to donate later. Blood banks in the United States may be required to label the blood if it is from a therapeutic donor, so some do not accept donations from donors with any blood disease. Others, such as the Australian Red Cross Blood Service, accept blood from donors with hemochromatosis. It is a genetic disorder that does not affect the safety of the blood.The donor's race or ethnic background is sometimes important since certain blood types, especially rare ones, are more common in certain ethnic groups. Historically, in the United States donors were segregated or excluded on race, religion, or ethnicity, but this is no longer a standard practice.
Recipient safety
Donors are screened for health risks that could make the donation unsafe for the recipient. Some of these restrictions are controversial, such as restricting donations from men who have sex with men because of the risk of transmitting HIV. In 2011, the UK reduced its blanket ban on MSM donors to a narrower restriction which only prevents MSM from donating blood if they have had sex with other men within the past year. A similar change was made in the US in late 2015 by the Food and Drug Administration. In 2017, the UK and US further reduced their restrictions to three months. In 2023, the FDA announced new policies easing restrictions on gay and bisexual men donating blood. These updated guidelines stipulate that men in monogamous relationships with other men, or who have not recently had sex, can donate. Individuals who report having sex with people who are HIV positive or have had sex with a new partner who has engaged in anal sex are still barred from blood donation. Autologous donors are not always screened for recipient safety problems since the donor is the only person who will receive the blood. Since the donated blood may be given to pregnant women or women of child-bearing age, donors taking teratogenic medications are deferred. These medications include acitretin, etretinate, isotretinoin, finasteride, and dutasteride.Donors are examined for signs and symptoms of diseases that can be transmitted in a blood transfusion, such as HIV, malaria, and viral hepatitis. Screening may include questions about risk factors for various diseases, such as travel to countries at risk for malaria or variant Creutzfeldt–Jakob disease. These questions vary from country to country. For example, while blood centers in Québec and the rest of Canada, Poland, and many other places defer donors who lived in the United Kingdom for risk of vCJD, donors in the United Kingdom are only restricted for vCJD risk if they have had a blood transfusion in the United Kingdom. Australia removed its UK-donor deferral in July 2022.
Directed donations from family members carry extra risks for the recipient. Any blood transfusion carries some risk of a transfusion reaction, but between genetically related family members, there are additional risks. The donated blood must be irradiated to prevent a potentially deadly graft-versus-host disease, which is more likely between genetically related people. Not all healthcare facilities have the equipment to do this on site. Alloimmunization is a particular risk for directed granulocyte donations. It is a common misconception that directed donations are safer for the recipient; however, family members and close friends, especially parents who have not previously donated blood, frequently feel pressured into lying about disqualifying risk factors and their eligibility, which can result in a higher risk of infection with bloodborne pathogens. Additionally, in the less common case of a person with leukemia or other bone marrow disease, a familial blood transfusion can trigger the production of alloantibodies against HLA proteins, which can cause a bone marrow transplant from that donor to fail in the future. A directed donation from an unrelated friend, however, would not have the same risk.