Blood donations

Blood can be collected ia the form of whole blood donations. In the United States, one unit, ie, 450 mL, of blood is collected from a healthy volunteer blood donor who is allowed to donate blood once every 10 weeks. A unit of blood is typically separated iato a red cell fraction, ie, red cell concentrate a platelet fraction, ie, random donor platelets (RDP) and plasma. 

Primary blood components iaclude plasma, red blood cells (erythrocytes), white blood cells (leukocytes), platelets (thrombocytes), and stem cells. Plasma consists of water dissolved proteias, ie, fibrinogen, albumins, and globulins coagulation factors and nutrients. The principal plasma-derived blood products are siagle-donor plasma (SDP), produced by sedimentation from whole blood donations fresh frozen plasma (FFP), collected both by apheresis and from whole blood collections cryoprecipitate, produced by cryoprecipitation of FFP albumin, collected through apheresis and coagulation factors, produced by fractionation from FFP and by apheresis (see Fractionation, blood-plasma fractionation). 

Transfusion-induced autoimmune disease has been a significant complication in the treatment of patients who require multiple platelet transfusions. Platelets and lymphocytes carry their own blood group system, ie, the human leukocyte antigen (HLA) system, and it can be difficult to find an HLA matched donor. A mismatched platelet transfusion does not induce immediate adverse reactions, but may cause the patient to become refractory to the HLA type of the transfused platelets. The next time platelets with an HLA type similar to that of the transfused platelets are transfused, they are rejected by the patient and thus have no clinical efficacy. Exposure to platelets originating from different donors is minimized by the use of apheresis platelets. One transfusable dose (unit) of apheresis platelets contains 3-5 x 10 platelets. An equal dose of platelets from whole blood donation requires platelets from six to eight units of whole blood. Furthermore, platelets can be donated every 10 days, versus 10 weeks for whole blood donations. 

Plasma Collection. Human plasma is collected from donors either as a plasma donation, from which the red cells and other cellular components have been removed and returned to the donor by a process known as plasmapheresis, or in the form of a whole blood donation. These are referred to as source plasma and recovered plasma, respectively (Fig. 1). In both instances the donation is collected into a solution of anticoagulant (146) to prevent the donation from clotting and to maintain the stabiUty of the various constituents. Regulations in place to safeguard the donor specify both the frequency of donation and the volume that can be taken on each occasion (147). 

Cellular cytokines (interferons, G-CSF) and immune response modifiers originally produced from human cells, most often leukocytes, have now been replaced with recombinant products with well-defined structure/function. Futuristic advances in experimental hematology portend development of human blood cells produced from the hemopoetic stem cells. Yet for the foreseeable future, homologous blood donated by healthy, altruistic voluntary blood donors remains the principal source of safe and adequate supply of blood and blood products for transfusion therapy. 

Oliaei F, Kriens D, Kessler K (2006) Investigation of perfluorochemical (pfc) contamination in minessota - phase one. Tech, rep., Report to Senate Environment Commitee Olsen GW, Church TR, Miller JP, Burris JM, Hansen KJ, Lundberg JK, Armitage JB, Herron RB (2003) Perfluorooctanesulfonate and other fluorochemicals in the serum of American Red Cross adult blood donators. EnvironHealth Perspect 111 1892-1901 Olsen GW, Burris JM, Ehresman DJ, Froehlich JW, Seacat JW, Butenhoff JL, Zobel LR... 

Treatment of anaemia associated with chronic disease Treatment of anaemia associated with cancer/chemotherapy Treatment of anaemia associated with prematurity To facilitate autologous blood donations before surgery To reduce transfusion requirements after surgery To prevent anaemia after bone marrow transplantation... 

Native factor VIII is traditionally purified from blood donations first screened for evidence of the presence of viruses such as hepatitis B and HIV. A variety of fractionation procedures (initially mainly precipitation procedures) have been used to produce a factor VIII product. The final product is filter-sterilized and filled into its finished product containers. The product is then freeze-dried and the containers are subsequently sealed under vacuum, or are flushed with an inert gas (e.g. N2) before sealing. No preservative is added. The freeze-dried product is then stored below 8 °C until shortly before its use. 

Factor IX obtained from blood donations is normally only partially pure. In addition to factor IX, the product contains lower levels of factors II, VII and X and has also been used to treat bleeding disorders caused by a lack of these factors. 

Before any blood donation is released for issue/processing, it must be tested for the presence of various pathogens particularly likely to be present in blood. In most countries, these tests include immunoassays capable of detecting ... 

Ender A et al. (2004) Screening of blood donations for HIV-1 and HCV RNA by transcription-mediated amplification assay one year experience. Transfus Med Hemother. 31 10-15. Kasermann F, Kempf C (1997) Photodynamic inactivation of enveloped viruses by buckminster-fullerene. Antiviral Res. 34 65-70. 

Blood donation Donors usually give about 500 mL of blood every two months. The loss is a little over 200 mg. 

Blood donation Because of isotretinoin s teratogenic potential, patients receiving the drug should not donate blood for transfusion during treatment and for 1 month after discontinuing therapy. 

Table 9.1. Major blood products that find therapeutic application. While all of these products are still sourced from human blood donations, a number of the protein-based products are now also produced by genetic engineering. Antibody preparations are considered in the next chapter...

L Which of the following statements describe why warfarin is not used to prevent blood coagulation in blood collection devices used at blood donating centers ... 

Unlabeled Uses Anemia associated with frequent blood donations, anemia in critically 111 patients, malignancy, management of hepatitis C, myelodysplastic syndromes... 

In France alone, about 220 000 plasmapheresis and 65 000 cytapheresis (collection of platelets, factor VIII, etc.) are performed every year, against 2 400000 blood donations. 600 ml of plasma can be collected from the same donor every 2 weeks if needed. 

President Jimmy Carter makes his 51st blood donation in a blood mobile at the White House. 

However, the emergence of variant Creutzfeldt-Jakob disease (vCJD) in the UK and France has raised concern about a new theoretical risk of infection in patients treated with blood and blood products (198). Animal experiments in which blood from sheep infected with bovine spongiform encephalopathy and natural scrapie-infected sheep into scrapie-free recipient animals have suggested disease transmission by the blood transfusion route in 2 of 24 sheep with bovine spongiform encephalopathy and in 4 of 21 sheep with scrapie (199). Many European countries have incorporated leukodepletion of all blood products, as leukocytes are believed to play a key role in the pathogenesis of variant Creutzfeldt-Jakob disease (198). In some countries, people who have lived in the UK for a period longer than 6 months between 1980 and 1996 are excluded from blood donation (13). Furthermore, it has been shown that various steps used in the manufacture of plasma-derived products also contribute to reduced infectivity by bovine spongiform encephalopathy (198). 

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