Donated blood

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. 

Calcium ions in blood trigger clotting. To prevent that in donated blood, sodium oxalate, Na2C204, is added to remove calcium ions according to the following equation. 

Blood contains about 0.10 mg Ca2+/mL. If a 250.0-mL sample of donated blood is treated with an equal volume of 0.160 M Na2C204, estimate [Ca2+] after precipitation. (K, CaC204 = 4 X 10-9)... 

Persons expressing 5 per cent or above of the normal complex levels experience less severe clinical symptoms. Treatment normally entails administration of factor VIII complex purified from donated blood. More recently, recombinant forms of the product have also become available. Therapeutic regimens can require product administration on a weekly basis, for life. About 1 in 10 000 males are born with a defect in the factor VIII complex and there are approximately 25 000 haemophiliacs currently resident in the USA. 

Immunoglobulins are purified from the serum (or plasma) of human donors by methods similar to those used to purify animal-derived antibodies. In most instances, the immunoglobulin preparations are enriched in antibodies capable of binding to a specific antigen (usually an infectious mi-croorganism/virus). These may be purified from donated blood of individuals who have recently ... 

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. 

Blood is also regularly tested, not just for blood group compatibility, but also for infections carried in the blood such as human immunodeficiency virus (HIV) and hepatitis B and C viruses. Early in the AIDS epidemic, before the AIDS virus was identified and a test developed to detect whether a person has been exposed to the virus, patients did contract HIV through blood transfusions. Today, every unit of donated blood is tested for the presence of HIV, as well as for hepatitis B and C viruses. 

Acitretin must not be used by women who are pregnant or may become pregnant while undergoing treatment or at any time for at least 3 years after treatment is discontinued. Ethanol must be strictly avoided during treatment with acitretin and for 2 months after discontinuing therapy. Patients must not donate blood during treatment and for 3 years after acitretin is stopped. 

Subjects were 14 healthy men and women who lived in the human metabolic unit of the Department of Human Nutrition and Food Service Management at the University of Nebraska-Lincoln. All meals were prepared and consumed in the metabolic diet kitchen. Subjects made complete urine and fecal collections throughout the study and donated blood samples biweekly. 

In severe cases of anaemia, or with ongoing blood loss, a blood transfusion may be necessary. Blood transfusions for anaemia are generally to be avoided due to adverse clinical outcomes, but in severe, acute bleeding, transfusions of donated blood are often lifesaving. 

There is a high prevalence of TTV all over the world (41-93%), with striking differences in the various countries. Japan has a prevalence of 39-68%. (553) In Hungary, 18.5% of healthy persons and 50.4% of patients with hepatitis of unknown aetiology tested positive. (567) In Brazil, donated blood was shown to contain TTV in 62% of cases. (560) In Germany, a TTV viraemia could be found in 14% of healthy donors and in 16-20% of the various risk groups. (563)... 

MacIntyre A, Gray JD, Gorelick M, Renton K. Salicylate and acetaminophen in donated blood. CMAJ 1986 135(3) 215-16. 

Individual portions of donated blood should be tested for infectious risk whenever possible. The series of assays currently performed in most countries comprises tests for antibodies against HIV-I/-II, HCV, and HTLV-I/II, HBsAg, and a test for syphilis. However, screening for syphilis is no longer mandatory in all countries, as cost-benefit analysis has shown it to be of little value, at least with voluntary non-remunerated donors. 

McOmish F, Yap PL, Jordan A, Hart H, Cohen BJ, Simmonds P. Detection of parvovirus B19 in donated blood a model system for screening by polymerase chain reaction. J Clin Microbiol 1993 31(2) 323-8. 

Epoetin alfa is indicated in anemic patients with chronic renal failure, including both those who require regular dialysis and those who do not. Epoetin alfa is also indicated in anemia associated with AIDS, treatment of AIDS with zidovudine, frequent blcKxl donations, and neoplastic dU-eases. It is indicated to prevent anemia in patients who donate blood prior to suigcry for future autologous transfusioas... 

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