A blood donor occurs when a person has voluntarily taken his blood and is used for transfusion and/or made into biopharmaceutical drugs by a process called fractionation (the separation of whole blood components). Donations can be whole blood (WB), or a particular component directly (the latter called apheresis). Blood banks often participate in the collection process and the procedures that follow.
Today in developed countries, most blood donors are unpaid volunteers who donate blood for the supply of society. In some countries, established stocks are limited and donors usually provide blood when family or friends need transfusions (direct donations). Many donors contribute as charitable acts, but in countries where donations are paid, some donors are paid, and in some cases there are incentives other than money like the time paid off. Donors can also be taken of blood for future use (autologous donations). Donate is relatively safe, but some donors have bruises where needles are inserted or may feel faint.
Potential donors are evaluated for anything that might make their blood unsafe to use. Screening includes testing for diseases that can be transmitted through blood transfusions, including HIV and viral hepatitis. Donors should also answer questions about medical history and conduct a brief physical exam to ensure donations are not harmful to their health. How often donors can contribute varies from day to month based on what components they donate and the laws of the country where donations take place. For example, in the United States, donors must wait eight weeks (56 days) between whole blood donors but only seven days between platelet pheresis donations and twice per seven-day period in plasmapheresis.
The amount of blood taken and the method varies. Collection can be done manually or with automatic equipment that only takes certain components of the blood. Most of the blood components used for transfusions have short shelf life, and maintaining a constant supply is a persistent problem. This results in an increased interest in autotransfusion, in which the patient's blood is saved during surgery for continuous reinfusion - or alternatively, is "self-donated" before when needed. (Generally, the idea of ​​"donation" does not refer to giving to someone self , although in this context it has become somewhat idiomatic.)
Video Blood donation
Donation type
Blood donors are divided into groups based on who will receive the collected blood. The 'allogeneic' contribution (also called 'homolog') is when the donor gives blood to be stored in a blood bank for transfusion to an unknown recipient. A 'directional' donation is when a person, often a family member, donates blood for transfusion to a particular individual. Donated donations are relatively rare when there is an available supply. Donors 'donor replacement' is a hybrid of both and is common in developing countries like Ghana. In this case, a friend or recipient family member donates blood to replace the stored blood used in the transfusion, ensuring a consistent supply. When a person has stored blood that will be transfused back to the donor at a later date, usually after surgery, called an 'autologous' donation. The blood used to make the drug can be made from allogenic donations or from donations exclusively used for manufacture.
Blood is sometimes collected using a similar method for blood-secreting, similar to the ancient practice of bloodshed, used to treat conditions such as hereditary hemochromatosis or polycythemia vera. This blood is sometimes treated as a blood donor, but can be immediately discarded if it can not be used for transfusion or further preparation.
The actual process varies according to state law, and recommendations for donors vary according to the collecting organization. The World Health Organization provides recommendations for blood donor policies, but in developing countries much of this is not followed. For example, the recommended testing requires laboratory facilities, trained staff, and special reagents, all of which may not be available or too expensive in developing countries.
An event in which donors come to donate alogenic blood is sometimes called 'blood drive' or 'blood donation sessions'. This can happen in blood banks, but they are often established in locations in communities such as shopping centers, workplaces, schools, or places of worship.
Maps Blood donation
Screening
Donors are usually asked to give consent to the process and this requirement means minors can not donate without the consent of a parent or guardian. In some countries, answers are linked to donor blood, but not names, to provide anonymity; in other countries, such as the United States, the names are stored to create an unqualified list of donors. If potential donors do not meet these criteria, they are 'suspended'. This term is used because many unqualified donors may be allowed to contribute later. Blood banks in the United States may be required to label blood if it is from a therapeutic donor, so some do not receive donations from donors with blood diseases. Others, such as the Australian Red Cross Blood Service, receive blood from donors with hemochromatosis. This is a genetic disorder that does not affect the safety of blood.
The race or ethnic background of the donor is sometimes important because certain blood types, especially the rare ones, are more common in certain ethnic groups. Historically, in the United States donors are separated or excluded on race, religion or ethnicity, but this is no longer a standard practice.
Receiver security
Donors are screened for health risks that can make the donation unsafe for the recipient. Some of these restrictions are controversial, such as limiting the contribution of men who have sex with men (MSM) due to the risk of HIV transmission. In 2011, the UK (excluding Northern Ireland) reduced the blanket ban on MSM donors to narrow restrictions that only prevent MSM from donating blood if they have had sex with other men in the past year. Similar changes were made in the US by the end of 2015 by the FDA. Autologous donors are not always screened for recipient safety issues because the donor is the only person who will receive blood. Because donated blood can be given to pregnant women or women of childbearing age, donors take teratogenic (birth defects cause) the drug is suspended. These medications include acitretin, etretinate, isotretinoin, finasteride and dutasteride.
Donors are examined for signs and symptoms of diseases that can be transmitted through blood transfusions, such as HIV, malaria, and viral hepatitis. Screening may include questions about risk factors for various diseases, such as travel to malarial risk countries or variants of Creutzfeldt-Jakob disease (vCJD). These questions vary from country to country. For example, while blood centers in QuÃÆ' Â © bec, Poland, and elsewhere postponed donors living in the UK for the risk of vCJD, donors in the UK were limited only to the risk of vCJD if they had a blood transfusion in the United Kingdom.
Donor security
Donors are also examined and ask specific questions about their medical history to ensure that donating blood is not harmful to their health. Hematocrit or hemoglobin levels of donors are tested to ensure that blood loss will not make them anemic, and this examination is the most common reason that donors are not eligible. Pulse, blood pressure, and body temperature are also evaluated. Elderly donors are sometimes also suspended at an age alone due to health problems. The safety of donating blood during pregnancy has not been thoroughly studied, and pregnant women are usually delayed up to six weeks after pregnancy.
Blood tests
Blood type of blood should be determined if blood is to be used for transfusion. Collecting agencies typically identify whether blood types A, B, AB, or O and Rh (D) donor types and will filter out antibodies against less common antigens. Further testing, including crosses, is usually done before transfusion. Group O is often referred to as a "universal donor" but this refers only to red cell transfusions. For plasma transfusions the system is reversed and AB is a universal donor type.
Most of the blood is tested for disease, including some STDs. The test used was a high sensitivity screening test and no actual diagnosis was made. Some test results are then found to be false positives using more specific testing. False negatives are rare, but donors are not encouraged to use blood donors for the purpose of anonymous STD screening because false negatives can mean contaminated units. Blood is usually discarded if the test is positive, but there are some exceptions, such as autologous donations. Donors are generally notified of test results.
Donated blood is tested by many methods, but the core test recommended by the World Health Organization is these four things:
- Hepatitis B Surface Antigen
- Antibodies against Hepatitis C
- Antibodies against HIV, usually subtypes 1 and 2
- Serological test for Syphilis
WHO reported in 2006 that 56 of the 124 countries surveyed did not use this baseline test on all blood donors.
Other tests for infectious transfusion infections are often used based on local requirements. Additional testing is expensive, and in some cases tests are not carried out because of the cost. These additional tests include other infectious diseases such as West Nile Virus, and babesiosis. Sometimes some tests are used for a single disease to cover the limitations of each test. For example, HIV antibody tests will not detect infected donors recently, so some blood banks use p24 antigen or HIV nucleic acid tests in addition to basic antibody tests to detect infected donors during the period. Cytomegalovirus is a special case in donor testing where many donors will test positive for it. This virus is harmless to healthy recipients, but may harm infants and other recipients with weakened immune systems.
Getting blood
There are two main methods to get blood from donors. The most common is just taking blood from the blood vessels as whole blood. This blood is usually separated into sections, usually red blood cells and plasma, since most recipients require only special components for transfusion. The typical contribution is 450 milliliters (or about one liter of US) of whole blood, although a 500-milliliter donation is also common. Historically, blood donors in India will only contribute 250 or 350 milliliters and donors in the People's Republic of China will contribute only 200 milliliters, although the larger 300 and 400 milliliters donations have become more common.
Another method is to draw blood from a donor, separate it using a centrifuge or filter, store the desired part, and return the rest to the donor. This process is called apheresis, and this is often done with machines designed specifically for this purpose. This process is very common for plasma and platelets.
For direct transfusion, the veins may be used but blood can be taken from the arteries. In this case, the blood is not stored, but it is pumped directly from the donor to the receiver. This is the earliest method for blood transfusion and is rarely used in modern practice. It was removed during World War II because of problems with logistics, and doctors who returned from treating injured soldiers set up banks to store blood when they returned to civilian life.
Site setup and drawing blood
Blood is taken from a large arm vein close to the skin, usually a median cubital vein on the inside of the elbow. The skin over the blood vessels is cleaned with antiseptics such as iodine or chlorhexidine to prevent skin bacteria from contaminating the collected blood and also to prevent infection where the needle penetrates the donor skin.
Large needles (16 to 17 gauge) are used to minimize shear forces that can physically damage red blood cells as they flow through the needle. A tourniquet is sometimes wrapped in the upper arm to increase blood pressure in the arm vein and speed up the process. Donors may also be asked to hold the object and blackmail it repeatedly to increase blood flow through the blood vessels.
Whole blood
The most common method is to collect blood from donor blood vessels into the container. The amount of blood taken varies from 200 milliliters to 550 milliliters depending on the country, but 450-500 milliliters is typical. Blood is usually stored in flexible plastic bags that also contain sodium citrate, phosphate, dextrose, and adenine sometimes. This combination keeps the blood from freezing and retains it during storage. Other chemicals are sometimes added during processing.
Plasma from whole blood can be used to make plasma for transfusion or can also be processed into other drugs using a process called fractionation. This is the development of the dry plasma used to treat the wounded during World War II and the variant on the process is still used to make other drugs.
Apheresis
Apheresis is a blood donor method in which blood is passed through a device that separates one particular constituent and returns the remainder to the donor. Usually the returned component is the red blood cells, the longest part of the blood being replaced. Using this method, one can donate plasma or platelets much more often than they can safely donate blood. This can be combined, with donors providing plasma and platelets in the same donation.
Platelets can also be separated from whole blood, but they must be collected from various donations. From three to ten units of whole blood is required for therapeutic doses. Plateletpheresis provides at least one full dose of each donation.
Plasmaferesis is often used to collect the plasma sources used to produce drugs such as plasma from whole blood. Plasma is collected at the same time as plateletpheresis sometimes called concurrent plasma .
Apheresis is also used to collect more red blood cells than usual in one donation (commonly known as "double red") and to collect white blood cells for transfusion.
Recovery and time between donations
Donors are usually kept on donation sites for 10-15 minutes after donating because most of the adverse reactions occur during or immediately after the donation. Blood centers usually provide soft drinks, such as orange juice and cakes, or lunch money to help recover donors. The needle site is covered with bandages and the donor is directed to keep the bandage for several hours. In hot climates, donors are advised to avoid dehydration (heavy exercise and games, alcohol) up to several hours after donations.
The donated plasma is replaced after 2-3 days. The red blood cells are replaced by the spinal cord into the circulatory system at a slower rate, averaging 36 days in healthy adult men. In one study, the range was 20 to 59 days for recovery. This rate of replacement is the basis of how often donors can donate blood.
Plasmapheresis and platelet pheresis donors may contribute more frequently because they do not lose significant numbers of red blood cells. The exact figure of how often donors can contribute differently from country to country. For example, plasmapheresis donors in the United States are allowed to donate large volumes twice a week and can nominally donate 83 liters (about 22 gallons) a year, while the same donors in Japan can only contribute every week and can only contribute about 16 liters ( about 4 gallons) in a year.
Red blood cells are a limiting step for overall blood donors, and the frequency of donations varies greatly depending on the type of donor and local policy. During a full blood donor, blood is drawn from the venipuncture area of ​​the inner arm of the right or left arm. Blood goes into the main collection bag located in the shaker next to the donor bed and the bag holds a whole pint of blood. After collecting blood bags along with three blood tubes for testing and typing are sent to the laboratory. Here, the blood bag is separated into different component parts in the centrifuge process (red blood cells, platelets, and plasma).
Iron supplements lowered the rate of suspension of donors due to low hemoglobin, both on first donor visits and on subsequent donations. Donors equipped with iron have hemoglobin and a higher iron shop. On the other hand, iron supplementation often causes diarrhea, constipation and abdominal discomfort of the epigastrium. The long-term effects of iron supplementation without iron storage measurements are unknown.
Complications
Donors are screened for health problems that will put them at risk of serious complications from donations. The first donors, teenagers, and women have a higher risk of reaction. One study showed that 2% of donors had a negative reaction to donations. Most of these reactions are small. A study of 194,000 donations found only one donor with long-term complications. In the United States, blood banks are required to report any deaths that may be related to blood donors. Analysis of all reports from October 2008 to September 2009 evaluated six events and found that five deaths were clearly unrelated to donations, and in the remaining cases they found no evidence that the donation was the cause of death.
Hypovolemic reactions can occur due to rapid changes in blood pressure. Fainting is generally the worst problem encountered.
This process has the same risk as other phlebotomy forms. Bruising the arm from needle insertion is the most common thing. One study found that less than 1% of donors had this problem. A number of less common complications of blood donation are known to occur. These include an arterial puncture, delayed bleeding, nerve irritation, nerve injury, tendon injury, thrombophlebitis, and allergic reactions.
Donors sometimes have a negative reaction to the sodium citrate used in the apheresis collection procedure to keep blood from clotting. Because the anticoagulant is returned to the donor along with the unbundled blood component, it can bind calcium in the blood of the donor and cause hypocalcemia. These reactions tend to cause tingling in the lips, but can cause seizures, seizures, hypertension, or more serious problems. Donors are sometimes given calcium supplements during donations to prevent these side effects.
In the apheresis procedure, the red blood cells are returned. If this is done manually and the donor receives blood from a different donor, a transfusion reaction may occur. Manual apheresis is very rare in developed countries because of this risk and automatic procedures as safe as the whole blood donor.
The last risk for blood donation is from equipment that has not been sterilized properly. In many cases, the appliances that come into contact with the blood are removed after use. Reusable equipment was a significant problem in China in the 1990s, and up to 250,000 blood plasma donors may be exposed to HIV from shared equipment.
Storage, supplies and requests
Storage and shelf lifeThe collected blood is usually stored in the blood bank as a separate component, and some of them have short shelf life. There is no storage solution to keep platelets for a long time, although some are being studied in 2008. The longest shelf life used for platelets is seven days.
The red blood cell (RBC), the most commonly used component, has a shelf life of 35-42 days at cooled temperature. For long-term (relatively rare) storage applications, this can be prolonged by freezing blood with a mixture of glycerol, but the process is expensive and requires a very cold freezer for storage. Plasma can be kept frozen for long periods of time and are usually given one year expiry date and keep supply less problem.
Request for blood
Limited storage time means it is difficult to have a blood supply to prepare for disaster. The subject is discussed at length after the September 11 attacks on the United States, and the consensus is that collection during disasters is impractical and that efforts should be focused on maintaining adequate inventory at all times. Blood centers in the US often have difficulty maintaining even a three-day supply for routine transfusion requests.
Donate level
The World Health Organization (WHO) recognizes World Blood Donor Day on June 14 each year to promote blood donation. This is the birthday of Karl Landsteiner, a scientist who discovered the ABO blood type system. The theme of the World Blood Donor Day 2012 campaign, "Every blood donor is a hero" focuses on the idea that everyone can become a hero by giving blood. In 2008, WHO estimates that more than 81 million units of blood are collected each year.
In the United States it is estimated that 111 million people are eligible for blood donation, or 37% of the population. But less than 10% of 37% of eligible blood donors donate each year. In the UK, the NHS reported a blood donation rate at "just 4%" while in Canada the figure was 3.5%.
Benefits of donor health
In patients susceptible to excess iron, blood donors prevent the accumulation of toxic quantities. Donating blood may reduce the risk of heart disease for men, but the association has not been established explicitly and probably from selection bias because the donors are screened for health problems.
Research published in 2012 showed that recurrent blood donors are effective in reducing blood pressure, blood glucose, HbA1c, low-density lipoprotein/high-density lipoprotein ratio, and heart rate in patients with metabolic syndrome.
Donor compensation
The World Health Organization set a goal in 1997 for all blood donors from unpaid volunteer donors, but by 2006, only 49 of the 124 countries surveyed had set this up as a standard. Some countries, such as Tanzania, have made great strides toward this standard, with 20 per cent of donors in 2005 being unpaid volunteers and 80 per cent in 2007, but 68 of the 124 countries surveyed by WHO have made little or no progress. Most plasmapheresis donors in the United States are still being paid for their donations. Donors are paid between $ 25 and $ 50 per donation. Some countries rely on paid donors to maintain adequate inventory. In some countries, such as Brazil and Australia, it is illegal to receive compensation, money or otherwise, for blood donations or other human tissues.
Regular donors are often given a kind of non-monetary recognition. A break from work is a common advantage. For example, in Italy, a blood donor receives a donation day as a paid holiday from work. Blood centers will also occasionally add incentives such as assurance that donors will have priority during disadvantages, free T-shirts, first aid boxes, glass scrapers, pens and similar trinkets. There are also incentives for people who recruit potential donors, such as prize drawings for donors and awards for successful drive organizers. The recognition of dedicated donors is common. For example, the Singapore Red Cross Society rewards voluntary donors who have made a number of donations under the Blood Donor Recruitment Program starting with a "bronze award" for 25 donations. The Malaysian government also offers outpatient and inpatient benefits for blood donation, for example, 4 months of free outpatient care and inpatient benefits after each donation. In Poland, after donating a certain amount of blood (18 liters for men and 15 for women), a person is given the title "Distinction Honorary Blood Donor" as well as a medal.
Most allogenic blood donors donate as a charitable act and do not expect to receive direct benefits from donations. Sociologist Richard Titmuss, in his 1970s The Gift Relationship: From Human Blood to Social Policy, compares the benefits of US and UK commercial and non-commercial blood donation systems, down in favor of the latter. The book became a bestseller in the US, resulting in laws to regulate private markets in the blood. This book is still referred to in the modern debate about turning blood into commodities. The book was re-published in 1997 and the same ideas and principles apply to analog donation programs, such as organ donation and sperm donations.
See also
- Blood substitute
- James Harrison (blood donor)
- List of blood donor agencies
- A man who has sex with a male blood donor controversy
- Xenotransfusion
References
Further reading
- Blood Donor and Processing
- How do youth support a blood emergency in Nepal?
- Deferred Donors: Anemia & amp; Blood Donor
- UK Guidelines for transfusion drugs
- Harrison E (Nov 2007). "Blood cell sold". Sci. Am . 297 (5): 108-9. doi: 10.1038/scientificamerican1107-108. PMIDÃ, 17990831.
(subtitle) There's more to blood banking than just bagging blood
Source of the article : Wikipedia
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