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Background: Although payment of blood donors is rejected by the WHO, FDA, EU and Red Cross, in Germany monetary compensation of expenses is permitted not only for plasmapheresis but

Adequate perioperative analysis of hemostasis taking into account also disorders of primary hemostasis considerably contributes to prevention, early detection, and appropriate treatment of hemostatic

1 Current Knowledge about the Pathogen 1.1 Characteristics of Hepatitis A Virus The clinical features of hepatitis A have been known for a long time. However, the pathogen (hepatitis A virus (HAV)) was firstly identified in 1973 with the aid of immune electron microscopy [1]. HAV is classified in the family of Picornaviridae , genus Hepatovirus . It is a small, spherical, non-enveloped virus with a diameter of approximately 30 nm. The capsid of the viral particle is made up of 60 copies of the three viral structural proteins VP1–VP3. The genome consists of a single- stranded (+)sense RNA molecule of 7,500 bases in length. The 5'' end of the genome is covalently bound to a small protein (VPg). The genome serves as messenger RNA and can be divided into three regions: a long open-reading frame (ORF) is flanked by the non-coding 5'' region and the non-coding 3'' region. The ORF encodes a polyprotein which is cleaved by proteolysis into the mature viral proteins. Two thirds of the genome code for non-structural proteins with enzymatic and regulatory functions. Translation is controlled by an ‘internal ribosomal entry site’ (IRES) located within the non-coding 5'' region [2]. Only one serotype of HAV has been identified so far. Analysis of HAV genome sequences has revealed 6 genotypes to date [3], with genotype I predominating worldwide. Genotypes IV–VI have only been observed in Old World monkeys. ...

Notfall- und Massivtransfusionen stellen eine besondere Herausforderung an den Kliniker und Transfusionsmediziner dar. Durch die erheblichen Fortschritte in der Präparation und Qualität von Blutkomponenten und Plasmaderivaten innerhalb der letzten 10 Jahre haben sich die spezifischen Risiken einer Massivtransfusion deutlich verringert. Sie korrelieren vor allem mit der Transfusionsgeschwindigkeit (Ersatz eines Blutvolumens innerhalb von 3 bis 4 Stunden) und/oder der Applikation großer Blutvolumina (mindestens 2 Blutvolumina innerhalb 24 Stunden). Mehr noch ist die individuelle Situation des Patienten für den weiteren Verlauf entscheidend. Auf der anderen Seite bringt die Notfalltransfusion eine Reihe spezifischer Risiken mit sich, welche nur durch entsprechende organisatorische Maßnahmen und definierte Substitutionsschemata beherrscht werden können. Diese unterscheiden sich je nachdem, ob Notfalltransfusionen bei Komplikationen im Rahmen elektiver Eingriffe oder bei Notaufnahmen erforderlich werden. Der Beitrag gibt Empfehlungen zur Durch-führung der Notfalltransfusion in diesen unterschiedlichen Situationen, um eine möglichst schnelle, sichere und effektive Blutversorgung der Patienten zu gewährleisten.

Objective: The aim of this study was to compare 2 test systems for red cell antibody screening. Materials and Methods: 30 fresh and 92 stored frozen samples with known red cell antibodies (rbc-abs)

The German National Advisory Committee ‘Blood’ (Arbeitskreis Blut), recently recommended testing of blood and plasma donations for antibodies against the hepatitis B core antigen (anti-HBc). We assessed possible effects of this intended measure on donor deferral rate and look back procedures. Study Design and Methods: 3,964 consecutive blood donors were tested for anti-HBc for the first time. Anti-HBc-positive samples were further investigated employing an alternative anti-HBc test, quantitative determination of anti-HBs and HBV nucleic acid testing. Results: 46 (1.16%) of the samples were tested specifically anti-HBc-positive. Following the recommendations of the Arbeitskreis Blut, 9 (0.23% of all) donors had to be permanently deferred. Eight of these were repeat donors and had already donated 353 blood components which had been transfused to 285 recipients during the past 17 years. Conclusions: Implementation of anti-HBc testing in Germany will result in an acceptable loss of blood donors. However, the realization of look-back procedures is problematic due to the huge number of transfused blood components, the long period of time those donors gave blood, and particularly the impossibility to precisely determine the time of seroconversion. Therefore, when introducing anti-HBc testing, regulatory authorities should consider the described implications for look-back procedures.

Based on several in vitro experiments, it has been suggested that autologous blood transfusion might lead to immunomodulation and that this effect might be prevented by leukocyte depletion. Clinica

This contribution was part of a public pro and con discussion during the 4th CAT symposium in Nottwil (Switzerland) and will focus predominantly on the pro arguments for preoperative autologous blood donation (PABD). A major advantage of PABD is the avoidance of the immunological problems associated with allogeneic transfusions. These can result in the delay of later transfusions and unavailability of compatible blood after immunization, leading to severe hemolytic transfusion reactions when red cell antibodies cannot be taken into account. Arguments will be presented that clearly show that transfusion of the wrong patient is expected less frequently with autologous blood products as long as general transfusion standards are observed. Unavoidable delayed hemolytic transfusion reactions, which occur after boostering of an undetectable antibody produced after an immunization in the past, cannot happen when autologous blood is administered. Furthermore, despite comprehensive testing for infectious diseases, allogeneic blood still bears the risk of transmission of infections due to blood donation in the window period, low-carrier status of the blood donor, or the emergence of new infectious agents. However, PABD should be adapted to the individual transfusion need of a patient for a given surgical intervention, should be carried out under optimized conditions, and should be included in a comprehensive concept of autologous hemotherapy. As part of such a concept, PABD constitutes a key element because it is, in contrast to other techniques, a preventive measure.

Introduction: We tested the feasibility of the determination of 24-hour recovery and survival time of transfused red blood cells (RBCs) by flow cytometry to evaluate a new RBC prepa

Background: Microwaves basically are a quick alternative to water bath and water bag system (WB) for thawing of fresh frozen plasma (FFP) for transfusion. Already in the 1980s we

New Guidelines for the Preparation of Blood and Blood Components and for the Use of Blood Components (Hemotherapy) – Alterations, Interpretations and Commentary (Part 2) Since Ju

Background: The influence of different preparation techniques and storage time on in vitro function of platelet concentrates (PC) was studied.

New Guidelines for the Preparation of Blood and Blood Components and for the Use of Blood Components (Hemotherapy) – Alterations, Interpretations and Commentary Since July 2000 the

Summary Background: The diminishing risks of allogeneic transfusion such as substantial reduction in transfusion-associated infections or prevention

Background: This study reports on the filtration efficiency and on functional changes of platelets filtered with the new Fresenius C4F thrombocyte apheresis set. Material and Methods:72 platelet concentrates were collected with a Fresenius AS 104 cell separator. Leukodepletion was performed with a leukocyte adsorption filter (Biofil P plus), integrated into the disposable apheresis system (C4F Fresenius). Residual leukocytes were counted microscopically using a Nageotte chamber. Granule membrane protein 140 (GMP-140) expression was determined by flow cytometry. Additionally, plasma β-thromboglobulin and platelet aggregation (ADP, collagen) were examined. Results:Filtration reduced the number of residual leukocytes from 27.6 ± 34.9 ×?106/unit (mean ± SD) to 0.45 ± 0.6 ×?106/unit (maximum 2.8 ×?106/unit). The median leukocyte reduction was 98.5% (50–99.9%), and platelet recovery was 91.5% (72.6–99.3%). Filtered platelets showed a significant decrease of in vitro aggregability (p Conclusion:In-line filtration with the Biofil P plus resulted in adequate leukocyte depletion and good platelet recovery. Filtration did not induce a release reaction ?β-thromboglobulin). Additionally filtered platelets did not show increased activation (GMP-140) but a decreased in vitro aggregability. The latter may be due to a selective retention of activated platelets by filter or the early time of filtration (1 h after separation). Whether the reduced in vitro aggregability is of clinical relevance is rather questionable.

Objective: The in vitro bleeding test (IVBT) is a sensitive and simple ex vivo method, simulating nonvascular primary hemostasis induced by injury of a small vessel. This review gives an overview of the factors influencing the test and describes the standard test after optimization at the Thrombostat 4000. The main intention is to summarize the various results obtained with this test and to indicate its possible application in the routine diagnostics. Of particular interest in this context is the development of the succeeding test system called the Platelet Function Analyzer (PFA-100). Data Sources and Selection Criteria: The literature since 1985 was analyzed reporting on the use of the IVBT for experimental and clinical reasons, and discussed by consideration of the own results and experiences. Results: After standardization and optimization and by consideration of the various variables influencing the method, the IVBT with the Thrombostat 4000 proved well-suited to detect very sensitively the inhibitory effect of aspirin and other drugs on platelet function. Therefore, it can be used for the control of thromboembolic prophylaxis with these drugs and the assessment of the perioperative bleeding risk of patients taking these drugs. Additionally, the IVBT can be a useful tool to document the perioperative and posttraumatic bleeding risk regarding disorders of the nonvascular primary hemostasis. This especially applies to hemodilution with particular respect to the influence of the infusion solutions administered. The IVBT proved to be clearly superior to the Simplate bleeding time (BT) for screening and control of therapy in von Willebrand’s disease and may replace the BT. The IVBT detects most of the congenital and acquired platelet disorders without being influenced by plasmatic coagulation disorders including those caused by therapeutic anticoagulation with heparin, heparinoids, hirudin, and coumarin. By the IVBT, the efficacy of drugs to improve the platelet function (e.g. desmopressin) can be controlled. There are several special in vitro applications of the test: detection of platelet-specific antibodies, quality control of platelet concentrates (PC), prediction of therapeutic efficacy of PC in non-immunized recipients. Finally, in a special modification (thrombocyto-penia-adapted IVBT) it can be even used to determine the bleeding risk and the efficacy of platelet transfusion in chronically thrombocytopenic patients ( < 50,000 platelets/μl). The disadvantage of the IVBT with the Thrombostat 4000 is that it shows still too much variation and needs too much labor and cost for general use as routine test. The succeeding method PFA-100 has considerably simplified the handling, although it has not solved all problems yet. The preliminary results document its superiority regarding the handling and the comparability of the results to those obtained with the Thrombostat 4000. Conclusions: The IVBT is a simple and sensitive tool to detect nonvascular disorders of primary hemostasis, which is well-suited for broad routine use if the new test system PFA-100 can be further developed.

Platelet transfusion practices in Europe are summarized based on survey questionnaire returns from 36 centers in 17 countries. In marrow hypoplasia the platelet transfusion trigger varied from 10,000 to 20,000/µl with a minority at 5,000/µl. These levels increased up to 50,000/µl in case of signs of major bleeding. In surgery levels of 50,000 to 100,000/µl were desirable with attempts to maintain postoperative levels of 30,000 to 50,000/µl for up to one week. A large majority of centers used random-pooled platelet concentrates (RPC) for surgical patients, while apheresis platelets were used by a small majority for chronic thrombocytopenic patients. HLA-matched platelets were used in most cases for immunized or refractory patients. An increasing majority prepares RPC by the buffy-coat technique. There is a tendency to store apheresis platelets for shorter times. Leukocyte-depleted platelets were used primarily for refractory chronic thrombocytopenic patients, although levels considered effective rang edfrom < 106 to < 108 About half the centers used leukocyte-depleted platelets in lieu of cytomegalovirus (CMV)-seronegative platelets. A large majority irradiated products for patients at risk of GvHD, although irradiation doses varied widely. The dose of platelets per transfusion also varied widely.

Background: Shortly after the gel test was introduced into routine immunohaemato-logy, an increased percentage of patients were reported to show a positive auto-control in the indirect antiglobulin test (IAT) of uncertain significance as the direct antiglobulin test (DAT) in the tube technique was negative. Materials and Methods: In our study 13,280 randomized patient blood samples were screened and additional investigations carried out including an analysis of patient histories in the 97 blood samples that were auto-control positive in the gel test. Results: In 87.4%, a re-testing with polyspecific antiglobulin serum (83.2% with anti-IgG) showed positive results in contrast to only 52.9% re-tested by the tube test. Neither nonspecificity nor cold agglutinins were significant. None of the patients examined showed any signs of haemolysis exept for one with pernicious anaemia. We concluded that the increased number of positive auto-controls and DATs is due to the greater sensitivity of the gel test and thus the detection of minute quantities of specific cell-bound IgG molecules, i. e. warm auto-antibodies or drug-induced antibodies. Conclusion: Prior to transfusion, a positive result should be confirmed by a tube DAT. If this test is negative and there is no history of a previous transfusion or of haemolysis, the transfusion should not be delayed by carrying out further time-consuming investigations.Schlüsselwòrter

Hintergrund: Pseudothrombozytopenie (PTP) ist ein In-vitro-Phänomen, bei dem die Plättchenzahl durch automatische Zählgeräte falsch-niedrig bestimmt wird. Meist fällt die Thrombozytopenie als Zufallsbefund ohne entsprechende Blutungs-neigung auf. Wird dieses Phänomen nicht erkannt, können Fehldiagnosen mit u.U. erheblichen therapeutischen Konsequenzen die Folge sein. Anhand von eígenen Fallen und einer eingehenden Literaturanalyse sollen Ursachen, Erscheinungsbild, Häufigkeit, diagnostische und klinische Probleme der PTP näher beleuchtet werden. Kasuistiken: Wir berichten über 3 Fälle, die postoperativ einen deutlichen Thrombozytenabfall aufwiesen. Der Befund wurde im Sinne einer Verbrauchskoagulopathie im Rahmen einer Sepsis oder einer heparininduzierten Thrombozytopenie Typ II fehlinterpretiert und -therapiert. In zwei Fallen wurden völlig unnötig Thrombozyten transfundiert. In alien drei Fallen konnte eine durch Kälteagglutinine bedingte PTP, die sich erst postoperativ entwickelte, als Grund für die niedrigen Thrombozytenwerte nachgewiesen werden. Schluβfolgerung: Aus den beschriebenen Fallen ist zu folgern, daβ sich eine PTP in der Klinik während des postoperativen Krankheitsverlaufs entwickeln kann. Wegen des groβen differentialdiagnositschen Spektrums wird postoperativ kaum an die PTP gedacht. Dadurch ist das Risiko einer Fehleinschätzung und fehlerhaften Behandlung der Thrombozytopenie in dieser Situation besonders groβ. Bei niedrigen Thrombozytenwerten sollte daher immer eine PTP ausgeschlossen werden, auch wenn die Thrombozytopenie anders erklärbar scheint.

Ziel: «Look-back»-Untersuchungen dienen der Aufdeckung von transfusionsassoziierten Infektionen und können gesicherte Auskunft über Infektionsrisiken bei Bluttransfusionen liefern. Design: Im Herbst 1993 wurde im Auftrag der Deutschen Gesellschaft für Immun-hämatologie und Transfusionsmedizin (DGTI) an alle staatlich-kommunalen und universitären Blutspendedienste ein Erhebungsbogen verschickt, der Daten zu Art und Umfang durchgeführter Look-back-Untersuchungen, zur Inzidenz HIV-1/2-positiver Blutspender und transfusionsassoziierter HIV-l/2-Infektionen abfragte. Der Fragebogen wurde von fast alien Instituten (n = 75) zurückgesandt und in an-onymisierter Form ausgewertet (lediglich von einem weiteren Institut liegen nur fernmündliche Angaben vor). Rahmen: Staatlich-kommunale Blutspendedienste in Deutschland (n = 76). Patienten: Alle Empfänger einer Blutkonserve bzw. von Blutprodukten im Zeitraum von 1985 bis Ende 1992, die in Kliniken innerhalb des Versorgungsbereichs der obengenannten Blutspendedienste behandelt wurden.

There exist no data yet about platelet storage in teflon bags. Therefore, a paired study has been performed to evaluate their suitability for the 5 day storage of platelet concentrates (PC) from the cell separator Fresenius AS-104. The PC’s of the AS-104 were stored in teflon as well as in polyolefin bags each (PL-732). In addition, PC’s of the Baxter CS-3000 were stored in PL-732. PH, cell counts, platelet morphology, aggregation, adherence and ADP/ATP concentration, plasma βTG, glucose, lactate and thrombin-antithrombin III complexes were investigated at day 0, 3 and 5 of storage. The results show that the teflon bags are quite suitable for 5 day storage of the PC’s. But the functional superiority of fresh PC’s from the AS-104 seemed to be reduced by storage in teflon bags compared to storage in PL-732. The unfavorable size and geometry of the teflon bags used could have been the cause. Therefore, size and geometry were consequently changed in the meantime.

The COBE Spectra was evaluated in 71 plateletpheresis procedures. Using the collection and anticoagulant algorithms of the system (n=57) we collected 4.3 ± 1.2×1011 platelets with a mean separation efficiency of 70.2+12.1%. The cell contamination was very low (leukocytes 0.5 ± 1.0×107, red cells 1.5 ± 2.2×107). In four different modifications of the standard separation protocols, we tried to reduce the ACD consumption in order to shorten the donation time and to improve donor safety. A constant ACD/blood ratio of 1 : 9 and increase of the blood flow to 50ml/min (n=14) caused significantly lower yields (3.1+0.7, p < 0.01) and visible spontaneous platelet aggregates in the collection line in 50% and in the PC’s in 29% of the runs. In orderto prevent platelet activation the ACD algorithm had to be maintained, but a reduction of the ACD/ blood ratio to about 15% was acceptable.

Die Risiken und Nebenwirkungen von Gerinnungspräparaten haben sich im Laufe der letzten Jahre durch die zunehmende Verbreitung von HIV einerseits und die Fortschritte in der Herstellung und Sterilisation der Gerinnungskonzentrate andererseits wesentlich geändert. Dementsprechend muβ die Indikation für die verschiedenen Gerinnungspräparate jeweils neu diskutiert werden, was in dem vorgelegten Beitrag geschieht. Auch unter Berücksichtigung des z. Zt. in Mitteleuropa noch kleinen Infektionsrisikos für Fresh Frozen Plasma (FFP) ist FFP noch immer das Mittel der Wahl für die Behandlung erworbener (komplexer) plasmatischer Gerinnungsstörungen. Gerinnungskonzentrate haben ihre Indikation dagegen in erster Linie bei angeborenen (isolierten) plasmatischen Gerinnungs-störungen. Nur bei excessiven oder sehr akut therapiebedürftigen erworbenen Gerinnungsstörungen sind Gerinnungskonzentrate ergänzend zu FFP erforderlich. Dies gilt auch für Antithrombin III, das bei erworbenem AT Ill-Mangel nur indiziert ist, wenn die Antikoagulation mit Heparin allein oder in Verbindung mit FFP nicht ausreichend möglich ist oder z. B. bei gleichzeitiger Thrombozytopenie die notwendige Heparindosis zu einem unvertretbaren Blutungsrisiko führen würde. In dieser Weise ist AT III gerade bei Verbrauchskoagulopathie ein wertvolles Therapeutikum. Im übrigen werden Angaben zur rationalen und rationellen Substitution von Gerinnungspräparaten gemacht, wobei auch auf die Möglichkeit weniger riskanter Ersatztherapeutika hingewiesen wird. Schlieβlich wird die Notwendigkeit einer adäquaten Gerinnungs-diagnostik hervorgehoben. Erfolgt diese in enger Kooperation zwischen Klinikern und Transfusionsmedizinern/Hämostaseologen, läβt sich die unnötige und inadäquate Applikation von Gerinnungspräparaten zum Nutzen der Patienten deutlich reduzieren.