Blood transfusion

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Blood transfusion is the process of transferring blood or blood-based products from one person into the circulatory system of another. Blood transfusions can be life-saving in some situations, such as massive blood loss due to trauma, or can be used to replace blood lost during surgery. Blood transfusions may also be used to treat a severe anaemia or thrombocytopenia caused by a blood disease. People suffering from hemophilia or sickle-cell disease may require frequent blood transfusions.

Contents 1 History 1.1 Early attempts 1.2 The first successes 1.3 Development of blood banking 1.4 The modern era 2 Precautions 2.1 Compatibility 2.2 Screening for infection 2.3 Processing of blood prior to transfusion 2.4 Neonatal transfusion 2.5 Terminology 3 Procedure 4 Blood donation 4.1 Contraindications to being a blood donor 5 Complications and risks 5.1 For the donor 5.2 For the recipient 5.3 Objections to blood transfusion 6 Animal blood transfusion 7 Blood transfusion substitutes 8 See also 9 References 10 External links

[edit] History

[edit] Early attempts

The first historical attempt at blood transfusion was described by the 15th-century chronicler Stefano Infessura. Infessura relates that, in 1492, as Pope Innocent VIII sank into a coma, the blood of three boys was infused into the dying pontiff's veins at the suggestion of a physician. The boys were ten years old, and had been promised a ducat each. All three died. Some authors have discredited Infessura's account, accusing him of anti-papalism.

With Harvey's discovery of the circulation of the blood, more sophisticated research into blood transfusion began in the 17th century, with successful experiments in transfusion between animals. However, successive attempts on humans continued to have fatal results.

The first fully-documented human blood transfusion was administered by Dr. Jean-Baptiste Denys on June 15, 1667. He transfused the blood of a sheep into a 15-year old boy, who recovered. Denys performed another transfusion into a labourer, who also survived. Both instances were likely due to small amount of animal's blood that was actually transfused into these people. This allowed them to withstand the allergic reaction. Then, Denys performed several transfusions into Mr. Mauroy, who on the third account had died (read "Blood and Justice"). Much controversy surrounded his death and his wife was accused of his murder; it's likely that the transfusion probably caused his death.

Richard Lower examined the effects of changes in blood volume on circulatory function and developed methods for cross-circulatory study in animals, obviating clotting by closed arteriovenous connections. His newly devised instruments eventually led to actual transfusion of blood.

"Many of his colleagues were present. . . towards the end of February 1665 [when he] selected one dog of medium size, opened its jugular vein, and drew off blood, until . . . its strength was nearly gone . . . Then, to make up for the great loss of this dog by the blood of a second, I introduced blood from the cervical artery of a fairly large mastiff, which had been fastened alongside the first, until this latter animal showed . . . it was overfilled . . . by the inflowing blood." After he "sewed up the jugular veins," the animal recovered "with no sign of discomfort or of displeasure."

Lower had performed the first blood transfusion between animals. He was then "requested by the Honorable [Robert] Boyle . . . to acquaint the Royal Society with the procedure for the whole experiment," which he did in December of 1665 in the Society’s Philosophical Transactions. On 15 June 1667 Denys professor in Paris carried out the first transfusion between humans and claimed credit for the technique, but Lower’s priority cannot be challenged.

Six months later in London, Lower performed the first human transfusion in England, where he "superintended the introduction in his [a patient’s] arm at various times of some ounces of sheep’s blood at a meeting of the Royal Society, and without any inconvenience to him.” The recipient was Arthur Coga, "the subject of a harmless form of insanity." Sheep’s blood was used because of speculation about the value of blood exchange between species; it had been suggested that blood from a gentle lamb might quiet the tempestuous spirit of an agitated person and that the shy might be made outgoing by blood from more sociable creatures. Lower wanted to treat Coga several times, but his patient wisely refused. No more transfusions were performed. Shortly before, Lower had moved to London, where his growing practice soon led him to abandon research. [1]

[edit] The first successes

The science of blood transfusion dates to the first decade of the 19th century, with the discovery of distinct blood types leading to the practice of mixing some blood from the donor and the receiver before the transfusion (an early form of cross-matching).

In 1818, Dr. James Blundell, a British obstetrician, performed the first successful transfusion of human blood, for the treatment of postpartum hemorrhage. He used the patient's husband as a donor, and extracted four ounces of blood from his arm to transfuse into his wife. During the years 1825 and 1830, Dr. Blundell performed 10 transfusions, five of which were beneficial, and published his results. He also invented many instruments for the transfusion of blood. He made a substantial amount of money from this endeavour, roughly $50 million in real dollars (adjusted for inflation).^{[citation needed]}

In 1840, at St. George's Hospital Medical School in London, Samuel Armstrong Lane, aided by Dr. Blundell, performed the first successful whole blood transfusion to treat hemophilia.

[edit] Development of blood banking

See also: Blood bank

While the first transfusions had to be made directly from donor to receiver before coagulation, in the 1910s it was discovered that by adding anticoagulant and refrigerating the blood it was possible to store it for some days, thus opening the way for blood banks. The first non-direct transfusion was performed on March 27, 1914 by the Belgian doctor Albert Hustin, who used sodium citrate as an anticoagulant. The first blood transfusion using blood that had been stored and cooled was performed on January 1, 1916. Oswald Hope Robertson, a medical researcher and U.S. Army officer, is generally credited with establishing the first blood bank while serving in France during World War I.

The first academic institution devoted to the science of blood transfusion was founded by Alexander Bogdanov in Moscow in 1925. Bogdanov was motivated, at least in part, by a search for eternal youth, and remarked with satisfaction on the improvement of his eyesight, suspension of balding, and other positive symptoms after receiving 11 transfusions of whole blood.

In fact, following the death of Vladimir Lenin, Bogdanov was entrusted with the study of Lenin's brain, with a view toward resuscitating the deceased Bolshevik leader. Tragically, but perhaps not unforeseeably, Bogdanov lost his life in 1928 as a result of one of his experiments, when the blood of a student suffering from malaria and tuberculosis was given to him in a transfusion. Some scholars (e.g. Loren Graham) have speculated that his death may have been a suicide, while others attribute it to blood type incompatibility, which was still incompletely understood at the time.^[1]

[edit] The modern era

Following Bogdanov's lead, the Soviet Union set up a national system of blood banks in the 1930s. News of the Soviet experience traveled to America, where in 1937 Bernard Fantus, director of therapeutics at the Cook County Hospital in Chicago, established the first hospital blood bank in the United States. In creating a hospital laboratory that preserved 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.

In the late 1930s and early 1940s, Dr. Charles Drew's research led to the discovery that blood could be separated into blood plasma and red blood cells, and that the components could be frozen separately. Blood stored in this way lasted longer and was less likely to become contaminated.

Another important breakthrough came in 1939-40 when Karl Landsteiner, Alex Wiener, Philip Levine, and R.E. Stetson discovered the Rhesus blood group system, which was found to be the cause of the majority of transfusion reactions up to that time. Three years later, the introduction by J.F. Loutit and Patrick L. Mollison of acid citrate dextrose (ACD) solution, which reduces the volume of anticoagulant, permitted transfusions of greater volumes of blood and allowed longer term storage.

Carl Walter and W.P. Murphy, Jr., introduced the plastic bag for blood collection in 1950. Replacing breakable glass bottles with durable plastic bags allowed for the evolution of a collection system capable of safe and easy preparation of multiple blood components from a single unit of whole blood. Further extending the shelf life of stored blood was an anticoagulant preservative, CPDA-1, introduced in 1979, which increased the blood supply and facilitated resource-sharing among blood banks.

[edit] Precautions

[edit] Compatibility

See also: Cross-matching and Blood type

Great care is taken in cross-matching to ensure that the recipient's immune system will not attack the donor blood. In addition to the familiar human blood types (A, B, AB and O) and Rh factor (positive or negative) classifications, other minor red cell antigens are known to play a role in compatibility. These other types can become increasingly important in people who receive many blood transfusions, as their bodies develop increasing resistance to blood from other people via a process of alloimmunization.

[edit] Screening for infection

See also: HIV blood screening

A number of infectious diseases (such as HIV, syphilis, hepatitis B and hepatitis C, among others) can be passed from the donor to recipient. This has led to strict human blood transfusion standards in developed countries. Standards include screening for potential risk factors and health problems among donors by determining donor hemoglobin levels, administering a set of standard oral and written questions to donors, and laboratory testing of donated units for infection. The lack of such standards in places like rural China, where desperate villagers donated plasma for money and had others' red blood cells reinjected, has produced entire villages infected with HIV.

As of mid-2005, all donated blood in the United States is screened for the following infectious agents:^[2]

• HIV-1 and HIV-2
• Human T-lymphotropic virus (HTLV-1 and HTLV-2)
• Hepatitis C virus
• Hepatitis B virus
• West Nile virus
• Treponema pallidum (the causative agent of syphilis)

When a person's need for a transfusion can be anticipated, as in the case of scheduled surgery, autologous donation can be used to protect against disease transmission and eliminate the problem of blood type compatibility.

[edit] Processing of blood prior to transfusion

Donated blood is sometimes subjected to processing after it is collected, to make it suitable for use in specific patient populations. Examples include:

• Leukoreduction, or the removal of stray white blood cells from the blood product by filtration. Leukoreduced blood is less likely to cause alloimmunization (development of antibodies against specific blood types), and less likely to cause febrile transfusion reactions. Also, leukoreduction greatly reduces the chance of cytomegalovirus (CMV) transmission. Leukoreduced blood is appropriate for:^[3]
  • Chronically transfused patients
  • Potential transplant recipients
  • Patients with previous febrile nonhemolytic transfusion reactions
  • CMV seronegative at-risk patients for whom seronegative components are not available
• Irradiation. In patients who are severely immunosuppressed and at risk for transfusion-associated graft-versus-host disease, transfused red cells may be subjected to irradiation with at least 2500 Gy to prevent the donor T lymphocytes from dividing in the recipient.^[4] Irradiated blood products are appropriate for:
  • Patients with hereditary immune deficiencies
  • Patients receiving blood transfusions from relatives in directed-donation programs
  • Patients receiving large doses of chemotherapy, undergoing stem cell transplantation, or with AIDS (controversial).
• CMV screening. Cytomegalovirus, or CMV, is a virus which infects white blood cells. Many people are asymptomatic carriers. In patients with significant immune suppression (e.g. recipients of stem cell transplants) who have not previously been exposed to CMV, blood products that are CMV-negative are preferred. Leukoreduced blood products can substitute for CMV-negative products, since the complete removal of white blood cells removes the source of CMV transmission (see leukoreduction above).

[edit] Neonatal transfusion

To ensure the safety of blood transfusion to pediatric patients, hospitals are taking additional precaution to avoid infection and prefer to use specially tested pediatric blood units that are guaranteed negative for Cytomegalovirus. It is uncertain whether leukodepletion can be adequate for the prevention of CMV, and therefore most guidelines recommend the provision of CMV-negative blood components for newborns or low birthweight infants in whom the immune system is not fully developed.^[5] These specific requirements place additional restrictions on blood donors who can donate to babies.

[edit] Terminology

The terms type and screen are used for the testing that (1) determines the blood group (ABO compatibility) and (2) checks for alloantibodies.^[6] It takes about 45 minutes to complete.

If time allows more extensive testing, a large number of antibodies are screened. This is known as group & screen and can take up to a day.^[6]

If there is no time the blood is called "uncross-matched blood". Uncross-matched blood is O-positive or O-negative. O-negative is usually used for children and women of childbearing age.

[edit] Procedure

Blood transfusions can be grouped into two main types depending on their source:

• Homologous transfusions, or transfusions using the stored blood of others.
• Autologous transfusions, or transfusions using one's own stored blood.

Blood can only be administered intravenously. It therefore requires the insertion of a cannula of suitable caliber. Before the blood is administered, the personal details of the patient are matched with the blood to be transfused, to minimize risk of transfusion reactions. With the recognition that clerical error (eg administering the wrong unit of blood) is a significant source of transfusion reactions, attempts have been made to build redundancy into the matching process that takes place at the bedside.

A unit (up to 500 ml) of blood is typically administered over 4 hours. In patients at risk of congestive heart failure, many doctors administer furosemide to prevent fluid overload. Acetaminophen and/or an antihistamine such as diphenhydramine are sometimes given before the transfusion to prevent a transfusion reaction.

[edit] Blood donation

Main article: Blood donation

Blood is most commonly donated as whole blood by inserting a catheter into a vein and collecting it in a plastic bag (mixed with anticoagulant) via gravity. Collected blood is then separated into components to make the best use of it. Aside from red blood cells, plasma, and platelets, the resulting blood component products also include albumin protein, clotting factor concentrates, cryoprecipitate, fibrinogen concentrate, and immunoglobulins (antibodies). Red cells, plasma and platelets can also be donated individually via a more complex process called apheresis.

Donations are usually anonymous to the recipient, but products in a blood bank are always individually traceable through the whole cycle of donation, testing, separation into components, storage, and administration to the recipient. This enables management and investigation of any suspected transfusion related disease transmission or transfusion reaction.

[edit] Contraindications to being a blood donor

Blood donation centers in different countries may have different guidelines about who can serve as a blood donor. Common contraindications to being a blood donor include:

• previous malaria or hepatitis
• a history of intravenous drug abuse
• donors who have received human-derived pituitary hormones
• donors with high-risk sexual behaviour (variably defined)
• donors who have previously been transfused (12-month min. deferral)

[edit] Complications and risks

[edit] For the donor

Donating whole blood at a modern, well-run blood collection center is safe. The biggest risk is probably that of vasovagal syncope, or "passing out". A large study, involving 194,000 donations during a one-year period at an urban U.S. blood center, found 178 cases of syncope, for an incidence of 0.09%.^[7] Only 5 of these incidents required emergency room attention, and there was one long-term complication. Most syncopal episodes occurred at the refreshment table following donation, leading the authors to recommend that donors spend at least 10 minutes at the refreshment table drinking fluids after donation. A Greek study of over 12,000 blood donors found an incidence of vasovagal events of 0.89%.^[8] Another study interviewed 1,000 randomly selected blood donors 3 weeks after donation, and found the following adverse effects:^[9]

• Bruise at the needle site — 23 percent
• Sore arm — 10 percent
• Hematoma at needle site — 2 percent
• Sensory changes in the arm used for donation (eg, burning pain, numbness, tingling) — 1 percent
• Fatigue — 8 percent
• Vasovagal symptoms — 5 percent
• Nausea and vomiting — 1 percent

None of these were severe enough to require medical attention in this study. There is no risk of acquiring an infection at a modern, well-run blood donation center.

Donation of blood products via apheresis is a more invasive and complex procedure and can entail additional risks, although this procedure is, overall, still very safe for the donor.

[edit] For the recipient

Main article: Transfusion reaction

There are risks associated with receiving a blood transfusion, and these must be balanced against the benefit which is expected. The most common adverse reaction to a blood transfusion is a so-called febrile non-hemolytic transfusion reaction, which consists of a fever which resolves on its own and causes no lasting problems or side effects.

Blood products can rarely be contaminated with bacteria; the risk of severe bacterial infection and sepsis is estimated, as of 2002, at about 1 in 50,000 platelet transfusions, and 1 in 500,000 red blood cell transfusions.^[10]

Transmission of viral infection is a common concern with blood transfusion. As of 2006, the risk of acquiring hepatitis B via blood transfusion in the United States is about 1 in 250,000 units transfused, and the risk of acquiring HIV or hepatitis C in the U.S. via a blood transfusion is estimated at 1 per 2 million units transfused.

Transfusion-associated acute lung injury (TRALI) is an increasingly recognized adverse event associated with blood transfusion. TRALI is a syndrome of acute respiratory distress, often associated with fever, non-cardiogenic pulmonary edema, and hypotension, which may occur as often as 1 in 2000 transfusions.^[11] Symptoms can range from mild to life-threatening, but most patients recover fully within 96 hours, and the mortality rate from this condition is less than 10%.^[12]

Other risks associated with receiving a blood transfusion include volume overload, iron overload (with multiple red blood cell transfusions), transfusion-associated graft-vs.-host disease, anaphylactic reactions (in people with IgA deficiency), and acute hemolytic reactions (most commonly due to the administration of mismatched blood types).

[edit] Objections to blood transfusion

Objections to blood transfusions may arise for personal, medical, or religious reasons. For example, Jehovah's Witnesses object to blood transfusion primarily on religious grounds, although they have also highlighted possible complications associated with transfusion.

[edit] Animal blood transfusion

Veterinarians also administer transfusions to animals. Various species require different levels of testing to ensure a compatible match. For example, cats have 3 blood types, cattle have 11, dogs have 12, pigs 16 and horses have 34.

The rare and experimental practice of inter-species blood transfusions is a form of xenograft.

[edit] Blood transfusion substitutes

Main article: Blood substitutes

As of mid-2006, there are no clinically utilized oxygen-carrying blood substitutes for humans; however, there are widely available non-blood volume expanders and other blood-saving techniques. These are helping doctors and surgeons avoid the risks of disease transmission and immune suppression, address the chronic blood donor shortage, and address the concerns of Jehovah's Witnesses and others who have religious objections to receiving transfused blood.

A number of blood substitutes are currently in the clinical evaluation stage. Most attempts to find a suitable alternative to blood thus far have concentrated on cell-free hemoglobin solutions. Blood substitutes could make transfusions more readily available in emergency medicine and in pre-hospital EMS care. If successful, such a blood substitute could save many lives, particularly in trauma where massive blood loss results.

[edit] See also

• Blood doping
• Yudin

[edit] References

[edit] External links

• The Serious Hazards of Transfusion (SHOT)
• New Scientist article on transfusion-associated lung injury

v • d • e  Transfusion medicine
Apheresis  (Plasmapheresis — Plateletpheresis — Leukapheresis) | Blood transfusion | Coombs test | Cross-matching | Exchange transfusion | International Society of Blood Transfusion | Intraoperative blood salvage | ISBT 128 | Transfusion reactions
Human blood group systems - Blood type
ABO | Colton | Duffy | Hh | Kell | Kidd | Kx | Rhesus |Yt
Blood products
Blood | Blood donation | Blood substitutes | Cryoprecipitate | Platelets | Plasma | Red blood cells