LITMIR.BIZ

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(Review list of countries in the UK) Were you a member of the U.S. military, a civilian military employee, or a dependent of a member of the U.S. military? From 1980 to the present, did you Spend time that adds up to 5 years or more in Europe? (Review list of countries in Europe.) Receive a blood transfusion in the United Kingdom or France? (Review country lists.) Have you ever Female donors: Been pregnant or are you pregnant now? Had a positive test for the HIV/AIDS virus? Used needles to take drugs, steroids, or anything not prescribed by your doctor? Received money, drugs, or other payment for sex? Had malaria? Had Chagas’ disease? Had babesiosis? Received a dura mater (or brain covering) graft or xenotransplantation product? Had any type of cancer, including leukemia? Had any problems with your heart or lungs? Had a bleeding condition or a blood disease? Have any of your relatives had Creutzfeldt–Jakob disease?

      Potential donors who have resided in or traveled to malaria‐endemic areas are deferred for 12 months. However, most transfusion‐transmitted malaria is associated with lengthy residence in malaria‐endemic areas rather than routine or short‐term travel, especially when short‐term travel is concentrated in tourist areas that may have little or no risk [19].

      Several questions related to AIDS risk behavior include whether the potential donor has had sex with anyone with AIDS risk factors, that is, given or received money or drugs for sex, had sex with another male (for males), or had sex with a male who has had sex with another male (for females). One area of inconsistency that has been eliminated involved whether males had sex with another male (MSM) at any time since 1977 (when HIV is thought to have entered humans). Previously, deferral had been indefinite, but this has been changed to 12 months to be consistent with other risk deferrals, and the reference to 1977 was eliminated. When the FDA changed this guidance regarding MSM in late 2015, it also committed to studying the effects of these changes on HIV risk in the blood supply through the Transfusion‐Transmissible Infections Monitoring System (TTIMS), a collaborative effort of the FDA, National Institutes of Health, and several major blood centers [20]. Although US data for the initial period since the changes have not yet been published, reports from Canada suggest that risk will not be greatly altered and that models used to estimate risk have been accurate [21–23]. In any case, when more data are available it may facilitate consideration of additional policy changes being tried in other countries, such as shorter (3 or 6 months) MSM deferral, or using other criteria to assess blood donor HIV risk that eliminates the MSM question.

      Transfusion recipients can theoretically harbor unknown infectious agents and perpetrate the cycle of transmissible disease, and so deferral of previous transfusion recipients has been considered. In one very large study, a previous transfusion history was found in 4.2% of donors. However, transfused and nontransfused donors had a similar incidence of positive viral screening tests and other deferrable risks [24], and thus receipt of transfusions is not a deferral criterion.

The medical history is an extremely effective part of ensuring the safety of the blood supply. For instance, the implementation of questions about behavior that would put potential donors at risk for HIV infection decreased the HIV infectivity of blood in the San Francisco Bay area by 90% even before the use of the HIV screening test [25]. One concern that remains even today has been that people who have engaged in high‐risk behavior might seek to donate blood to obtain a test for HIV. In some situations, this seems to be true. Of 30 HIV‐positive blood donors in Paris, 47% had known risk behaviors and 50% admitted to having donated to obtain a test for HIV [26]. In a larger study of HIV‐seropositive blood donors, their reasons for donating in spite of having participated in behavior that placed them at risk for HIV infection included failure to read carefully or comprehend the deferral information, group pressure, a desire to be tested, and belief that the testing would identify any infected blood [27]. Despite concerns raised by this study, overall, blood donors have a lower rate of transmissible disease test results than the general population.

      Occasionally, situations arise in which the donor’s physician believes that donation would be safe, but the blood bank does not accept the donor. For instance, some medications may make the individual unsuitable as a blood donor because of the condition requiring the medication, while other medications may be potentially harmful to the recipient. Many other conditions must be evaluated individually by the blood bank physician, whose assessment of conformance with FDA regulations, which consider blood a pharmaceutical, may not always coincide with another physician’s view of the health of the potential donor.

      Patients with hemochromatosis as blood donors

      Hereditary hemochromatosis is genetically determined. The use of phlebotomy to reduce iron stores and prevent progression of the disease continues to be the therapy of choice. Blood obtained by therapeutic phlebotomy of patients with hemochromatosis was not acceptable for transfusion when the pathogenesis of the disease was not understood. Approximately two‐thirds of patients with hemochromatosis are probably eligible as blood donors, and thus about 65% of the units drawn during iron‐depletion therapy would be suitable for transfusion. Since 2016, the FDA has allowed blood banks to collect units for transfusion from this population, although this resource has not become fully utilized. Previous survey estimates suggested this could provide 200,000 to 3 million units [28] of blood annually in the United States. Studies show that risk for a positive test for transfusion‐transmitted infections is not greater from patients with hemochromatosis than from regular blood donors, and a National Institutes of Health pilot program was able to include these patients as 7% of their donor population, who supplied 11% of red blood cell units for transfusion and research [29–31].

      Physical examination of the blood donor

      The physical examination of a potential donor includes determination of the donor’s temperature, pulse, blood pressure, weight, and hemoglobin. Each of these has FDA‐mandated limits. In addition, the donor’s general appearance and behavior are assessed for any signs of illness or the influence of drugs or alcohol. The skin at the venipuncture site is examined for signs of intravenous drug abuse, lesions suggestive of underlying disease, and local lesions that might make it difficult to cleanse the skin and thus lead to contamination of the blood unit during venipuncture.

      There are weight requirements for donors because it is necessary to balance the amount of blood collected in relation to the donor’s estimated blood volume and also the amount of blood in relation to the volume of anticoagulant in the collection container. To integrate the volumes of blood collected with the weight ranges of donors, an arbitrary lower weight limit of 110 pounds has been established. There is no upper weight limit, although extremely obese potential donors may have other health problems or inadequate venous access that could preclude donation. The pulse should be regular and between 50 and 100 per minute, although potential donors who have a slower pulse related to involvement in an active exercise program may donate with approval of the transfusion medicine physician.

Although hemoglobin may still be estimated by a manual screening method in which a drop of blood is placed in a copper sulfate solution of a known specific gravity, in developed countries, automated microhematocrit is most often used, and in less well‐developed countries,

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