(Jrt)
Blood Transfusion
History
Blood transfusion is very old: the history of ancient Egyptians and the Treaty of anatomy Herophilus to mention. In the fifteenth century, Pope Innocent VIII was allegedly subjected to this treatment. In most of these attempts, the blood used was of animal origin.
In 1492: Pope Innocent VIII suffered the first "treatment" of living cells by drinking the blood of three boys ten years three times a day. Children die, followed shortly by the pope.
In 1616: William Harvey, an English doctor was the first to demonstrate that blood circulates through the body and it does not stagnate. This proves that blood is used to carrying something but at the time it is unclear what.
In 1667: Jean Baptiste Denis, a very famous french doctor at the time, personal physician to Louis XIV, is the first to inject the blood of an animal to a man. It injects the blood of a lamb to a young man suffering from typhus (gastro-enteritis fatal at that time). The man died shortly after what appears to be the first blood transfusion. The same year, Denis and his colleague Emmeretz conducting the first transfusion between humans in the artery connecting one of the subjects in the vein of the other.
In 1668: The french court decides that only doctors so-called "competent" would be allowed to make blood transfusions because most people who received transfusions at the time died shortly afterwards. The court also asked before each transfusion experience at least one animal.
In 1788: You can now show that a dog weakened by loss of blood has only need an injection of blood to be resuscitated. So the same is possible for men. We also know now that blood is used to carry oxygen essential for life.
In 1818: During this year, the first transfusions of blood from human to human are taking place. The blood of animals is no longer used because too many patients died. It is hoped more results with human blood but doctors at that time unaware of the existence of blood groups ABO system and Rhesus group .. So little chance of success, but much more than the blood of animals. The primary beneficiaries are women after childbirth, weakened by the loss of blood.
In 1820: The transfusion with blood animal resurfaced a small appearance because many problems arise as the human blood clotting (much faster than that of animal blood), but also many diseases and epidemics spread through human blood.
In 1900: Austrian, Karl Landsteiner discovered the concept of different blood groups (A-AB-BO), comparing the blood of different subjects. He noted that blood agglutine or not with red blood cells from other patients. Now the most successful transfusions. He received the Nobel Prize for medicine in 1930.
In 1916: First success by Albert Hustin on the preservation of human blood: by adding sodium citrate, it is almost more clots.
In 1918: During the first war many advances have been made in medicine and in particular on the blood. It was during these years that the first "true" transfusions take place on a large scale (taking into account transfusions of blood groups).
In 1940: Karl Landsteiner and his compatriot Wiener discover all the factor rhesus monkey named after the race macaque used in the experiment. The transfusions are becoming increasingly safer for recipients.
This is Charles Richard Drew conceptualisa and who organized the first blood bank, which allowed blood to bring the British during the Second World War, between 1940 and 1941.
From 1985 to 1990 (case of contaminated blood): 4400 people are infected with the AIDS virus after administration of blood products. (See below: risks; risks of infection.)
In 1993 (January): Many laws are signed to ensure the safety of both donors and recipients at the donation and transfusion. The government wants to encourage donations to save the most lives and to avoid a shortage.
In 1998 (April): Filtration systematic blood (whole blood, plasma, platelets) to eliminate the white blood cells (leukoreduction).
In 2000 (January): Creation of the French Blood Establishment, single operator of blood transfusion in France. The employees are not volunteers, they are employees of the plant.
In 2001 (July): A very sensitive screening (known as genomics) of the AIDS virus and hepatitis C is made on each donation. This research drirecte virus by molecular biology used to detect possible contamination of the donor before his seroconversion (appearance of antibodies).
Transfusions counterparts
The blood from a human donor other than the patient himself to the condition that blood groups are compatible between donor and recipient.
* Transfusion concentrates globular
Shall be preserved red blood cells, white blood cells being eliminated by leukoreduction, thus reducing the risk viral and immunological.
* Perfusion platelet concentrates
Do serves as for the fight against bleeding disorders, especially in cases of bone marrow failure.
* The blood plasma
Its conservation requires freezing (heat preservation of proteins) to -25 ° C. The shelf life of frozen human plasma is one year. In France, all plasma from whole blood are donated to LFB (Laboratory of the French Division and Biotechnology) at Ulis in the Paris region. The LFB's role is to extract and purify molecules necessary for certain patients such as anti hémophilique for example. Only plasmas obtained by apheresis (sample only plasma from a donor) are transfused unchanged. There are two types of plasma therapeutics: PVA (method inactivation physico-chemical) and plasma secure. (Donating plasma is isolated at least 120 days, pending the back where the donor at the time, it is verified that all legal markers (HIV, syphilis, hepatitis ...) are still negative.)
Transfusion autologous
* Transfusion deferred autologous (TAD) or autologous. In anticipation of a particularly bleeding, it is possible to collect several units of blood in the five weeks preceding, store and inject them during the procedure act. The risk of viral contamination is zero, there is no immunological risk, but risk blight is the same or higher depending on the age and pathology of the patient, for a homologous transfusion.
* Transfusion of blood recovered from the surgical bleeding. The red blood cells are sucked recovered, washed and reinjected. This method requires a preparation and special equipment and can not go to a special aseptic surgery (vascular or bone) and outside of any infectious disease or cancer.
The red blood cells
The transfusion of packed red blood cells (blood red) today replaces that of whole blood. These red cells are in good standing obtained from whole blood, exceptionally by apheresis. These concentrates can be kept 42 days at a temperature set legally between 2 ° C and 6 ° C. It concentrates transfused red blood cells to treat anemia related to either a hemorrhage or a bone marrow failure, is an anomaly synthesis of hemoglobin or red cell membrane. The transfusion is given if anemia is poorly supported clinically or presenting a particular risk, in pregnant women, for example. The indication of transfusion in other anemia is questionable, especially in hemolytic anemia auto-immune or deficiencies of iron or vitamins.
Platelets
We can concentrate platelets from whole blood from several donors (initial process). You can also now take in a single apheresis donor, ie that it takes blood from the donor on an automatic machine which, by differential centrifugation, retains a portion of platelets and returns the blood depleted in platelets to the donor.
This technique apheresis can take enough platelets for a single donor (about 4 x 1011, or 400 billion) to treat a patient. Platelets donor regenerate quickly enough because it produces 100 to 200 million per minute. The donation of platelets is used to treat certain diseases that cause lack thereof, as leukemias and aplasies. The leukemias are cancers of the blood. It uses chemotherapy to kill cancer cells, but it also kills non-diseased cells, including platelets, hence their lack. The aplasia is a disease where the bone marrow, the body which produces blood cells no longer work.
The platelet concentrates have a duration of 5 days under constant agitation and maintained between 20 ° C and 24 ° C in order to keep all their activities hemostatic.
The plasma
The levy plasma is produced by apheresis. The process is relatively similar to the levy of platelets, apart from that we collect about 600 ml of plasma donor who returns on its depleted blood plasma.
Once removed, the plasma can be kept one year at -25 ° C, is transfused either unchanged or split into its various elements: albumin, coagulants factors and antibodies. The antibodies are injected in the event of immune disorder (immune deficiency, autoimmune disease ...), or to prevent infection when exposed to a risk of contamination (eg tetanus, hepatitis B ...). The albumin (a protein) and total plasma are transfused to burn them lose through the skin, and serious injuries. Factors coagulants them, are used to treat certain diseases hemorrhagic: hemophilia, for example.
The risks and complications
The transfusion risk exists, but remains lower than the risk of not being transfused if the indication of a transfusion has been well laid. The viral risk is much better apprehended since the 90 years, which has limited sharply after that date, and sometimes excessively, the use of transfusions. Since 2005, we are seeing an increase in transfusions of 3% per annum. This increase is due to two reasons. On the one hand, better product safety, and a decrease in fear of their use (partly linked to the diagnosis viral genomic research of HIV and HCV by molecular biology) which resulted in a sharp decrease of autologous transfusion Deferred (TAD). On the other hand an increase in life expectancy and the number of senior-related "papy boom." The refractory anaemia and hip prostheses are infrequent young subjects ...
The risks are of immunological, infectious, or transfusion-related volumes:
Risks immunological
* Incompatibility erythrocyte transfusion: it is a priori excluded by the tests done on the donor and the recipient.
o the accident ABO, often severe, should no longer be as perfectly avoidable, and always due to human error.
o outside this case, the transfusion is considered safe by 98% (it was therefore 2% of incidents, of which very little result in a death. The most common of these incidents are a reaction "thrill-fever", and passenger reaction benign).
* Incompatibility leuco-platelet, due to the presence of HLA antibodies in the donor, which can cause serious lung damage, TRALI, English acronym (transfusion related acute lung injury) for acute lung damage transfusion.
* Purpura post transfusion, several days after a transfusion of platelets counterparts. The patient destroyed its own platelets.
Finally, a simple ineffectiveness transfusion may be linked to an antibody present in the recipient vis-à-vis an antigen on the transfused figurative elements. Antibodies anti-erythocytaire for red blood cells, anti-HLA antibodies ABO and anti HPA for platelets.
If a person is transfused with a concentrated erythrocyte inconsistent, it can cause the death of the patient: the antibody response, and this causes hemolysis intra vascular acute, with DIC, haemoglobin (plasma pink or red) and hemoglobinuria (dark red urine) , And leads to irreversible collapse. If the person is conscious, she sometimes felt a strong pain in the lumbar; during surgery, can be seen bleeding ribbon. In some cases, there will be no reaction by immunodeficiency, but also some cases of unexplained unresponsiveness. If you saw them in time, the patient must be treated with hemodialysis.
In France, an accident ABO (some fifty cases per year) results in a death rate of 10 to 20%.
It should be noted that cases of transfusion blind, which was before the discovery of blood type, but also still practice today in developing countries because of the lack of analysis, we may we estimate that approximately 64% chance that the donation is compatible. If the transfusion is reserved for serious case, we can estimate in a unit transfusant blind, which saves on two patients out of three. With two units, this proportion drops to four out of ten.
Risks of infection
* Risk blight, caused by bacterial contamination of the product transfusions. This type of accident is rare but very serious. This risk transfusion has profoundly changed the habits of requirements in recent years, resulting in a limitation of indications and alternatives (work on the artificial blood ...). The risk the world's largest, less controlled, and can lead to fatal accidents (the first cause of accidental fatal post-transfusion, even before the accident ABO), is essentially blight, contamination during the sampling could result in the recipient to sepsis or toxic shock therapy, especially for concentrated platelets which keep at room temperature (22 ° C) promoting the development of bacteria. It minimizes the risk in adopting stringent aseptic procedures at the time of sampling, by refusing any donor feverish. Pockets of current levy would allow routine screening laboratory without "open" the container (in itself a source of contamination), but it is not yet a legal obligation. In addition we must not lose sight of the fact that bacteriological examinations require a lot of time, things sometimes difficult to reconcile with products life very limited, as platelets (5 days).
* Even better controlled today, perhaps because of the excessive media coverage that has put forward in 90 years, is the viral risk (viral hepatitis, CMV, HIV…), who does that exceptionally today contamination. This probably explains the decline in recent years the demand for protocols deferred autologous (lower requirements of the order of 50%, benefiting from simple transfusion counterpart). It minimizes the risk in trying to detect by questioning the possible carriers of the virus, to reject the "donor at risk." The laboratory testing on blood donors accepted, including screening viral genomics, can further reduce this risk that currently goes to zero, while maintaining a high media profile.
* Three cases of transmission of Creutzfeldt-Jakob through blood transfusions have been reported in 2006. These prion diseases pose other problems unresolved directly (no technical possibility of screening). Only a foreclosure targeted (family history, "chrono-geography") can minimize the risk.
It minimizes these risks into three stages:
* Selection of donors. Before the donation, the donor has an interview with a doctor who warned of the risks he is running to the recipient of his blood if it is contaminated. The doctor also gives advice and assesses the risk of disease in the donor (it may be in a phase where it can not be detected). It can refuse the gift (10 to 25% of cases), adviser to the donor to analyses of his blood in the laboratory or wait a few months before the end of treatment.
* Analysis of blood collected. Some viruses or their serological markers such as AIDS and hepatitis B and C are systematically searched and some parasitic sérologies (malaria, Chagas disease) may be a function of the past geographically donor.
* Treatment of blood collected. The apheresis plasma transfusions are either subject to quarantine in anticipation of a serological testing of the donor (plamas secure), is treated industriellemnt solvent detergent (plasmas viro mitigated SD). Two processes inactivation plasmas are currently (2008) to the test, treatment or methylene blue, either by amotosalen the family of psoralens. Unfortunately, out of possible treatment of platelets by the amotosalen, all these processes are not suitable for blood cells (blood and platelets) because they would be destroyed.
The plasma from whole blood donations are sent to LFB for the manufacture of medicinal products derived from blood. This production includes many steps inactivation bacterial, parasitic and viral. Treatments for alcohol, pepsin, chromatographies, ultrafiltration, pasteurization are implemented according to the drug product.
The traceability of blood transfusion remains essential in order to be able to go back to the donor in case of trouble.
Read also Anemia
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