Blood transfusion

Blood transfusion is the process of receiving blood products into one's circulation intravenously. Transfusions are used in a variety of medical conditions to replace lost components of the blood. Early transfusions used whole blood, but modern medical practice commonly uses only components of the blood, such as red blood cells, white blood cells, plasma, clotting factors, and platelets.

History

Early attempts

The first historical attempt at blood transfusion was described by the 17th 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 (through the mouth, as the concept of circulation and methods for intravenous access did not exist at that time) at the suggestion of a physician. The boys were ten years old, and had been promised a ducat each. However, not only did the pope die, but so did the three children. Some authors have discredited Infessura's account, accusing him of anti-papalism.

Beginning with Harvey's experiments with 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, eminent physician to King Louis XIV of France, on June 15, 1667. He transfused the blood of a sheep into a 15-year old boy, who survived the transfusion. Denys performed another transfusion into a labourer, who also survived. Both instances were likely due to the small amount of blood that was actually transfused into these people. This allowed them to withstand the allergic reaction. Denys' third patient to undergo a blood transfusion was Swedish Baron Bonde. He received two transfusions. After the second transfusion Bonde died. In the winter of 1667, Denys performed several transfusions on Antoine Mauroy with calf's blood, who on the third account died.

First successful transfusion

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, then a professor in Paris, carried out the first transfusion between humans and claimed credit for the technique, but Lower's priority cannot be challenged.

Development of blood banking

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, 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 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. Bogdanov died 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 not completely understood at the time.

Complications of transfusions

Transfusions of blood products is associated with several complications, which can be broadly categorized as immunologic transfusion reactions, or non-immunologic complications. Immunologic reactions include acute hemolytic reactions, delayed hemolytic reactions, febrile nonhemolytic reactions, allergic reactions, and transfusion purpura. Nonimmunologic complications include infections, volume overload, lung injury, hypothermia, and coagulopathy. The risks of complications usually increase with increasing frequency and volume of transfusion.

Immunologic reactions

Acute hemolytic reactions occur with transfusion of red blood cells, and occurs in about 0.016 percent of transfusions, with about 0.003 percent being fatal.This is due to destruction of donor erythrocytes by preformed recipient antibodies. Most often this occurs due to clerical errors or improper typing and crossmatching. Symptoms include fever, chills, chest pain, back pain, hemorrhage, increased heart rate, shortness of breath, and rapid drop in blood pressure. When suspected, transfusion should be stopped immediately, and blood sent for tests to evaluate for presence of hemolysis. Treatment is supportive. Kidney injury may occur due to the effects of the hemolytic reaction (pigment nephropathy).

Delayed hemolytic reactions occur more frequently (about 0.025 percent of transfusions) and are due to the same mechanism as in acute hemolytic reactions. However, the consequences are generally mild and a great proportion of patients may not have symptoms. However, evidence of hemolysis and falling hemoglobin levels may still occur. Treatment is generally not needed, but due to the presence of recipient antibodies, future compatibility may be affected.

Febrile nonhemolytic reactions are due to recipient antibodies to donor white blood cells, and occurs in about 7% of transfusions. This may occur after exposure from previous transfusions. Fever is generally short lived and is treated with antipyretics, and transfusions may be finished as long as an acute hemolytic reaction is excluded.

Allergic reactions may occur when the recipient has preformed antibodies to certain chemicals in the donor blood, and does not require prior exposure to transfusions. Symptoms include urticaria, prutitus, and may proceed to anaphylactic shock. Treatment is the same as for any other type 1 hypersensitivity reactions. A small population (0.13%) of patients are deficient in the immunoglobin IgA, and upon exposure to IgA-containing blood, may develop an anaphylactic reaction.

Posttransfusion purpura is a rare complication that occurs after transfusion containing platelets that express a surface protein HPA-1a. Recipients who lack this protein develop sensitization to this protein from prior transfusions, and develop thrombocytopenia about 7–10 days after subsequent transfusions. Treatment is with intravenous immunoglobulin, and recipients should only receive future transfusions with washed cells or HPA-1a negative cells.

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. 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%. Although the cause of TRALI is not clear, it has been consistently associated with anti-HLA antibodies. Because these types of antibodies are commonly formed during pregnancy, several transfusion organisations have decided to use only plasma from men for transfusion . TRALI is typically associated with plasma components rather than packed red blood cells (RBCs), though there is some residual plasma in RBC units.