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At least 19 recordsLinked to original sources
PubMed1975

[Providing of polytraumatized persons with blood transfusion, blood derivatives and infusion solutions].

The therapy by blood transfusion, blood plasma and infusion solutions, duration and dosage are individual for each patient and dependent on the previous state of health of a patient, size of injure, degree of bleeding, expressed shock and disturbed general state. For taking care of the polytraumatized persons and especially for taking care of the parenhematozic organs and gastrointestinal bleedings greater quantities of blood are required. We assessed the seriousness of shock and hypovolemia on the basis of the clinical picture, decreased arterial pressure, haemogram, hematocrytes and diuresis. On assessing hypovolemia we used the size of opening and depth of wound, as well as the size of extremity. In treatment of polytraumas there is need for harmonious cooperation of surgeons, orthopedists, transfusiologists, röntgenologists etc. Traumatism is an important and difficult problem of the society and health care; it requires imperatively better organization of the first aid service, medical care on the spot of injury, then, in transport, greater and better organized traumatological and transfuzion service, training and scientific research.

Blood Transfusion↗
PubMedDate not supplied

Blood transfusion, blood storage and immunomodulation.

Allogeneic blood transfusion is the most frequent allotransplantation procedure performed on a routine basis with no prior HLA-typing. Roughly 50% of the recipients of unprocessed red cells and platelets become alloimmunized. Evidence also exists for some degree of transfusion-induced immunosuppression. Prior transfusion has been shown to enhance kidney transplant survival and evidence of an increase in tumor recurrence and of infectious complications has also been presented. The presence of donor antigen-presenting cells appears to be a prerequisite for alloimmunization and they must be both viable and capable of presenting a costimulatory signal in order to induce IL-2 secretion and proliferation of responding CD4 T cells. APCs presenting antigen but no costimulatory signal can induce non-responsiveness in CD4 T cells, a possible mechanism of transfusion-induced immunosuppression. APCs in refrigerated blood continue to present antigen but progressively lose their ability to provide costimulation. By day 14 costimulatory capacity is absent and transfusion of such blood should not alloimmunize but could induce some degree of immunosuppression. Further refrigerated storage in excess of 2 to 3 weeks leads to induction of apoptosis in contaminating leukocytes. We have found that alloantigens-expressed on such cells do not appear to be recognized by responder T cells and transfusion of blood stored in excess of 3 weeks should neither alloimmunize nor immunosuppress.

Antigen-Presenting Cells↗
PubMed1978

Increased pulmonary arteriovenous shunting in humans following blood transfusion. Relation to screen filtration pressure of transfused blood and prevention by Dacron wool (Swank) filtration.

Transfusion through standard filters to dogs of stored blood containing microaggregates results in an increase in pulmonary arteriovenous shunting (Qs/Qt) and a decreased diffusion capacity of the lung for O2. These effects are due to microemboli that pass the filters and are prevented by use of Dacron wool (Swank) micropore transfusion filters. It was the purpose of this study to determine whether alterations in pulmonary shunting occur in humans following transfusions of stored blood through standard transfusion filters. In eight patients transfused over 20% of blood volumes through standard filters, Qs/Qt and alveolar-arterial O2 tension differences increased significantly. These changes did not occur in patients transfused comparable amounts of blood through Dacron wool (Swank) filters or in patients transfused less than 20% of blood volumes. A direct correlation was found between the absolute percent change in Qs/Qt and the quantity of microaggregates passing the filter and present in the transfused blood. It is concluded that removal from stored blood of microaggregates by administration of the blood through effective micropore transfusion filters prevents an increase in Qs/Qt caused by administration of such material.

Adult↗
PubMed2000

Immunomodulation by blood transfusions.

Blood transfusions can affect the immune response in two opposite ways. They may either lead to immunization or to tolerance induction. Immunization is reflected by the induction of HLA alloantibodies and T cell activation while the induction of tolerance is suggested by the enhanced graft survival in transfused versus non-transfused recipients. The immunological mechanism leading to downregulation of the alloimmune response is not clear. One possible explanation is the induction of a Th2 response by non-professional antigen presentation by the transfused blood cells. On the other hand, evidence is accumulating that the degree of HLA compatibility between transfusion donor and patient is a determining factor. Transfusions sharing at least one HLA-DR antigen with the recipient induce tolerance while fully HLA-DR mismatched transfusions lead to immunization. The importance of the degree of HLA-DR sharing suggests a central role for CD4+ regulatory T cells. We hypothesize that indirect recognition of an allopeptide in the context of self-HLA-DR on the transfusion donor by CD4+ T cells of the recipient might be the clue to tolerance induction. Preliminary data show indeed that CD4+ T cells specific for an allopeptide in the context of self HLA-DR are able to downregulate the alloimmune response of autologous T cells. Further analysis of transplanted patients, who have received an HLA-DR shared transfusion, should reveal whether such CD4+ regulatory T cells are indeed responsible for the beneficial effect of pretransplant blood transfusions.

Animals↗
PubMed2001

Modulation of the alloimmune response by blood transfusions.

Blood transfusions can induce both immune activation and immunosuppression. The former is expressed by the induction of HLA alloantibodies and T cell activation, while the latter is accompanied by enhanced graft survival in transfused versus non-transfused recipients. The immunological mechanism leading to downregulation of the alloimmune response has not yet been elucidated. Possible explanations include the induction of a Th2 response by non-professional antigen presentation by the transfused blood cells and blockage of alloreactive T cell reactivity by soluble HLA and soluble FasL in the supernatant of blood components. These mechanisms, however, do not explain the observations which have shown that the degree of HLA compatibility between the transfusion donor and patient is a determining factor. Transfusions in which the donor blood shares at least one HLA-DR antigen with the recipient induce tolerance, while fully HLA-DR mismatched transfusions lead to immunization. The importance of HLA-DR sharing suggests a central role for CD4+ regulatory T cells. In this case, indirect recognition of an allopeptide in the context of self-HLA-DR on the transfusion donor by CD4+ T cells of the recipient might be the clue to the induction of tolerance. Recent data from our laboratory in fact show that CD4+ T cells specific for an allopeptide in the context of self HLA-DR are able to downregulate the alloimmune response of autologous T cells. As these regulatory T cells produce IL-10, they may also be involved in the extension of tolerance via their modulatory effect on dendritic cells. It remains to be established whether these regulatory T cells are indeed responsible for the 'blood transfusion effect' in organ transplantation.

Blood Transfusion↗
PubMed2003

[European Union and blood transfusion].

Blood transfusion is progressing, Europe is growing, European blood transfusion organisations are developing rapidly. The first step was the publication of a new directive (2002/98/CE). The directive is the result of a compromise between technocracy, lobbying and blood transfusion professionals. European blood transfusion must be based on medical, scientific and social criteria. Two imperatives must be considered: the respect of ethics and; independence from the commercial system. The primary objective is to give satisfaction to patients while respecting blood donors.

Blood Banks↗
PubMed1984

[Immunologic selection of renal transplant donors and recipients: blood transfusions].

Blood transfusions clearly improve the prognosis of cadaver kidney transplantation. The percentage of graft survival at one year is increased, about + 25%. Preoperative transfusions are effective, whereas peroperative transfusions are ineffective. The following technique seems to be good. Each patient should first receive 5 blood transfusions over a short time lapse, and then one unit of blood from time to time, two times per year for example. The blood must be less than three days old and must contain leucocytes. Transfusions induce, in a few hemodialysed patients, an anti-HLA immunisation. It is thus necessary to choose a donor with a negative cross-match. Transfusions induce in many patients a better tolerance for kidney transplant. This tolerance is perhaps immunologically specific. Blood transfusions are also useful for the selection of related donors HLA semi identical with recipients. The recipient is transfused several times with donor's blood. Transplantation is only performed when the cross-match remains negative and then leads to a high percentage of success.

Antibody Formation↗