Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Platelet Transfusion”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources
PubMed1996

A flow cytometric platelet immunofluorescence crossmatch for predicting successful HLA matched platelet transfusions.

Platelet crossmatching may provide a useful way of selecting donors for effective platelet transfusions in patients refractory to random donor platelet concentrates due to alloimmunization. We assessed the predictive value of a flow cytometric platelet immunofluorescence crossmatch test for the outcome of HLA matched platelet transfusions in a group of alloimmunized patients. Platelet immunofluorescence (PIFT) crossmatches were performed for 104 HLA-matched platelet transfusions administered to 30 patients. A negative PIFT crossmatch correctly predicted a successful platelet transfusion (1 h post-transfusion platelet recovery >20%) in 56/75 (75%) cases. We also considered non-immunological factors that, in combination with alloimmunization, might have contributed to an unsuccessful transfusion result, i.e. fever, septicaemia, splenomegaly, disseminated intravascular coagulation and bleeding. The predictive value of a negative PIFT crossmatch was better when these non-immunological factors were absent [48/59 (81%) correct predictions] than when these factors were present [8/16 (50%) correct predictions] (P=0.01; chi-square test). The effect of ABO incompatibility between donor and recipient on the predictive value of the PIFT crossmatch was also analysed. Positive PIFT crossmatches occurred more frequently in ABO incompatible donor-recipient combinations [in 18/28 (64%) cases] than in ABO-compatible donor-recipient combinations [in 11/76 cases (14%)] (P<0.001, chi-square test). Successful platelet transfusions were observed on 53/76 (70%) occasions in ABO compatible transfusions as compared to 16/28 (57%) in ABO incompatible transfusions. This difference was not statistically significant (P=0.23; chi-square test). Consequently, a negative PIFT crossmatch appeared to be non-predictive for the transfusion outcome in cases of ABO incompatibility between donor and recipient. We conclude that the PIFT crossmatch for platelet donor selection in addition to matching for HLA antigens, is predictive for the outcome of ABO compatible transfusions in alloimmunized recipients and prediction levels are increased when non-immunological causes for platelet refractoriness are absent.

ABO Blood-Group System↗
PubMed1990

[ABO blood groups and platelet transfusion].

Platelet transfusion without regard for AB0 compatibility is controversially discussed. Therefore, we studied the success of 136 AB0 compatible and 52 incompatible platelet applications in 37 patients. Our results suggest, that AB0 matching can improve the response of platelet transfusion.

ABO Blood-Group System↗
PubMed1979

Platelet transfusions.

Platelets play a pivotal role in hemostasis by forming the initial hemostatic plug and augmenting the formation of the more permanent fibrin thrombus. Thrombocytopenia may lead to bleeding, which can be treated with therapeutic platelet transfusions or prevented with prophylactic transfusions. While many advances have been made in platelet transfusion technology, problems remain. These include the short storage life of liquid-stored platelets and the frequent development of alloantibodies (the refractory state) in patients receiving a number of transfusions. Significant progress, however, is being made in both areas.

Antigens↗
PubMed2001

Status of platelet collection and platelet transfusion.

Platelet product derived from single donor plateletpheresis is required to reduce the risks of adverse reactions by blood transfusion. The objectives of this study are to evaluate the status of platelet collection and its efficacy by various kinds of plateletpheresis equipment and to assess the achievement of platelet transfusion by platelet product derived from a single donor. Since the blood centers have introduced some kinds of efficient plateletpheresis equipment, large units of platelet products have been supplied mainly for the patients. Amicus and CCS might be preferable plateletpheresis machines because of their collection efficiencies and wider indication for donors. The average number of donors of platelet product per patient has recently reached nearly 1.0, and around 90% of patients have received platelet product derived from a single donor in the recent several years. However, platelet transfusion derived from a single donor has not yet been completely achieved. Each regional blood center should seriously consider the efficacy of each plateletpheresis equipment and arrange the equipment to collect platelets more effectively to achieve platelet transfusion from a single donor.

Blood Platelets↗
PubMedDate not supplied

Effect of heparin reversal and fresh platelet transfusion on platelet emboli post-cardiopulmonary bypass in a pig model.

Heparin reversal by protamine and fresh platelet transfusion may decrease bleeding complications post-cardiopulmonary bypass (CPB) and may increase the level of organ trapped platelet emboli. Platelet emboli were quantified in two groups of 12 Yorkshire pigs (30-35 kg), where 111indium labeled autologous platelets (INPLT: 850-1,200 microCi) were injected intravenously before and after CPB (BCPB, ACPB), and the platelet emboli level in intact organs and their samples (brain, heart, kidneys, lung, liver, and spleen) was quantified with an ion chamber and a gamma counter, respectively. All pigs were systemically heparinized (ACT > 400 sec). CPB was carried out at 2.5-3.5 L/min at 28 degrees C using a centrifugal pump, an oxygenator (OX:Bentley Univox 1.8 m2), an arterial filter (AF:0.25 m2), and a cardiotomy reservoir (CR: BMR 250) for 90 min. Heparin was reversed with an equivalent dose of protamine. The percent of INPLT dose (ID%, mean +/- SD) in organs of BCPB and ACPB pigs was calculated. The sequence of platelet emboli on a unit weight basis (ID%/g) had the following order: Spleen > Liver > Lung > Kidneys > Heart > Brain. The presence of significantly higher levels of emboli in brain, heart, and kidneys in the ACPB than the BCPB group suggest that platelet transfusion after heparin reversal with protamine may increase the risk of platelet emboli. However, it is an acceptable risk for patients having bleeding complications post-CPB.

Animals↗
PubMed1995

Causes of refractoriness to platelet transfusion.

Platelet refractoriness is a multifactorial problem that often leads to aggressive measures in an attempt to treat a thrombocytopenic patient. Identification of the underlying causes should allow for prevention and management regimens to improve both transfusion practice and patient outcome. A number of clinical studies have evaluated the relative importance of the various causes of refractoriness. Unfortunately, most are significantly compromised by uncontrolled confounding factors. The causes can be broken down into three categories based on the source of the problem: clinically determined, patient related, or blood bank determined. This breakdown can help to identify appropriate prevention and circumvention measures. Additional causes worthy of increased attention are the platelet transfusion trigger and the tendency for prophylactic transfusion. Improvements in transfusion practice may offer the greatest hope for limiting the complications of platelet transfusion and refractoriness.

Antigens, Human Platelet↗
PubMed1995

The use of anti-D to improve post-transfusion platelet response: a randomized trial.

Patients undergoing induction chemotherapy for acute leukaemia often become refractory to platelet transfusions. Increased clearance of transfused platelets due to alloimmune destruction has been identified as one of the primary mechanisms contributing to this refractory state. We performed a double-blind randomized trial to determine whether the administration of anti-D to Rh-positive individuals could prevent the refractory state and improve post-transfusion platelet response. Rh-positive patients with acute leukaemia undergoing induction chemotherapy and requiring platelet transfusions were allocated to weekly intravenous anti-D (20 micrograms/kg) or placebo. Platelets and red cell concentrates were administered according to standardized transfusion guidelines. Outcome measures included platelet transfusion utilization, red cell utilization, platelet recovery 18-24 h post-infusion, and the percentage of patients refractory to platelet transfusion. There were 43 patients studied: 21 received anti-D and 22 saline placebo. The mean number of platelet concentrates required per day of observation was 0.59 (SD 0.22) in the anti-D group and 0.61 (SD 0.22) in the placebo group, P = 0.86. No difference was detected between groups in terms of platelet recovery post-infusion, refractoriness to platelet transfusion or frequency of infection (P = 0.97). Red cell concentrate utilization was significantly increased in the anti-D group compared to the placebo group, 0.58 units per day versus 0.37 units per day respectively, P = 0.005. We conclude that the use of anti-D did not improve post-transfusion platelet response in Rh positive patients with acute leukaemia, but did result in an increased need for red cell transfusion.

Acute Disease↗
PubMed1999

Characterization of liposomes carrying von Willebrand factor-binding domain of platelet glycoprotein Ibalpha: a potential substitute for platelet transfusion.

Platelet glycoprotein (GP) Ib/IX/V complex is a receptor for von Willebrand factor (vWf), which plays a crucial role in primary hemostasis by mediating platelet adhesion to injured blood vessels. We have expressed in CHO cells a fragment of GPIba that retained a vWf-binding function. The recombinant fragment (rGPIba) was incorporated into liposomes and evaluated their functions in vitro. rGPIba on the liposome surface was detectable by flow cytometric analysis. Addition of vWf and ristocetin caused specific agglutination of rGPIbalpha-liposomes, as evaluated by an aggregometer or a fluorescent microscopy. When ristocetin was added to platelet-rich plasma (PRP) pre-mixed with rhodamine-labeled rGPIbalpha-liposomes, platelets aggregated and rhodamine-fluorescence was strongly positive in the platelet thrombi, suggesting that heterologous aggregation (attachment of liposomes to platelets) occurred. Platelet aggregation in PRP at low platelet concentration (20-80 x 10(6)/ml) was enhanced by rGPIbalpha-liposomes in a dose-dependent manner. Thus, rGPIbalpha-liposomes may accumulate on vWf-exposed subendothelial tissues and enhance platelet function in vivo, supporting hemostasis in thrombocytopenic individuals.

Animals↗
PubMed1999

Platelet-bound immunogloblins before and after platelet transfusion: measurement of in vivo binding.

In routine tests to investigate immunological mechanisms as a cause for enhanced destruction of transfused platelets; serum from the patient is tested against a panel of donor lymphocytes and platelets to demonstrate the presence of antibodies against HLA or platelet specific antibodies. Here we describe a flow cytometric technique in which in vivo binding of immunoglobulins (Ig) is measured. By comparing the histograms of the platelet suspensions before and after transfusion, four different patterns were obtained: no Ig binding before and after transfusion (pattern 1), pre-existent Ig binding (patterns 2 and 3) or preferential Ig binding to the transfused platelets (pattern 4). This technique was tested in 164 random platelet transfusions and 34 HLA-matched platelet transfusions. A statistically significant association was found between pattern 1 and a negative result of the indirect platelet immunofluorescence test for the detection of antibodies in the serum taken before the transfusion studied or a good platelet recovery and between pattern 4 and a positive indirect platelet immunofluorescence test or a low platelet recovery.

Autoimmunity↗
PubMed1981

Evidence that circulating immune complexes remove transfused platelets from the circulation.

Fifteen recently diagnosed patients with acute leukemias admitted for induction chemotherapy were selected for study. When thrombocytopenic (venous platelet count less than 20 X 10(9)/l) these patients received prophylactic platelet transfusions. A total of 67 platelet transfusion therapies were administered and evaluated. Using the Raji cell radioimmunoassay, the serum concentrations of circulating immune complexes (CIC) were measured immediately before and 10-12 hr after each platelet transfusion. In 36 instances, elevated values of CIC were present in the recipient's pretransfusion samples. The corresponding posttransfusion values being significantly lower (P less than 0.05). Furthermore, in those 36 instances the mean percentage for the posttransfusion platelet increment was significantly lower (P less than 0.001) than in the remaining 31 instances in which normal pretransfusion values of CIC were measured. We conclude that CIC were an important factor in rapidly removing transfused platelets from the circulation, thereby, adversely affecting the benefit of platelet transfusions.

Acute Disease↗
PubMed1998

Successful treatment of platelet transfusion refractoriness: the use of platelet transfusions matched for both human leucocyte antigens (HLA) and human platelet alloantigens (HPA) in alloimmunized patients with leukaemia.

Six patients, 4 with acute myeloid leukaemia and 2 with a myelodysplastic syndrome who were refractory to random donor platelet transfusions and alloimmunized to human leucocyte antigens (HLA) and human platelet alloantigens (HPA), were treated with HLA- and HPA-matched platelet transfusions. In all the patients refractoriness and alloantibodies to HLA as well as HPA-1b or HPA-5b were detected simultaneously. Sixty-seven transfusions (445 units) of HLA- and HPA-matched platelets were given and responses to them were, in general, satisfactory in all the patients. No major spontaneous bleeding occurred. Four patients underwent bone marrow transplantation despite alloimmunization. The percentages of platelet transfusion days with a platelet nadir below 20x10(9)/l were 88% for the last 3 random donor platelet transfusions and 39% for the first 3 HLA- and HPA-matched platelet transfusions, respectively (p=0.009, Fisher's exact test). Four patients received also HLA-matched platelets, but responses to them were poor. The small number of transfusions with HLA-matched platelets precluded comparisons to either the random donor or HLA- and HPA-matched platelet transfusions. It seems that HLA- and HPA-alloimmunized patients can be successfully supported with HLA- and HPA-matched platelet concentrates.

Adult↗
PubMed1988

Refractoriness to platelet transfusion after single-donor consecutive platelet transfusions and its relationship to platelet antibodies.

In thirty patients with acute leukemia and severe aplastic anemia receiving random single donor platelet transfusions, the development of refractoriness by consecutive platelet transfusions with cytapheresis and its relationship to the appearance of anti-platelet antibodies were investigated. The median number of platelet transfusions inducing refractoriness was 13 times, and 20% of the patients remained unrefractory despite of the repeated multiple platelet transfusions up to 20 to 25 times. The results of anti-platelet antibody tasts by the enzyme-linked immunosorbent assay(ELISA) and immunofluorescent techniques(IFT) showed no statistically significant relationship with the refractoriness (p greater than 0.1). Although there was significant correlation between the results of ELISA and IFT, both tests were insufficient to find out refractoriness even with the use of pooled platelets from multiple donors as target cells. This study shows that 13 single donor platelet transfusions result in refractoriness, that both ELISA and IFT are insufficient to detect refractoriness despite of their significant correlation, and that other methods than these are needed in order to detect alloimmunization.

Adolescent↗
PubMed2006

Immature platelet fraction measurement: a future guide to platelet transfusion requirement after haematopoietic stem cell transplantation.

summary. The decision to prophylactically transfuse platelets is dependent on the platelet count, careful regular clinical assessment and agreed local protocol. The ability to predict when platelet recovery will occur should allow a more reasoned approach to platelet transfusion. An increase in reticulated platelets demonstrates impending platelet recovery. A new rapid automated method to assess reticulated platelets, the immature platelet fraction (IPF), is described, and its clinical utility assessed. The IPF is identified by flow cytometry with the use of a nucleic acid specific dye in the reticulocyte channel on the Sysmex XE-2100. Fifty healthy adult volunteers were used to establish the normal range. Patients where platelet marrow production or destruction might be abnormal were studied, and some patients followed serially during treatment. Thirty patients receiving cytotoxic chemotherapy were tested, and 13 of these patients followed serially. Fifteen patients post-autologous or allogeneic transplant were followed daily for platelet count and IPF percentage to monitor platelet recovery. The method demonstrates good reproducibility and stability. The recovery phase of thrombocytopenia in most chemotherapy and transplant patients was preceded by a rise in IPF percentage several days prior to platelet recovery. In particular, patients undergoing autologous transplantation (n = 8) using peripherally collected stem cells have a characteristic IPF percentage motif, with a rise one or two days prior to engraftment. The automated IPF is a useful parameter in the clinical evaluation of the thrombocytopenic patient and has the potential to allow optimal transfusion of platelet concentrates.

Adult↗
PubMed1998

Transfusing platelets 2 h after the completion of amphotericin-B decreases its detrimental effect on transfused platelet recovery and survival.

Platelet transfusion support is required during bone marrow aplasia following ablative chemotherapy and bone marrow progenitor cell transplantation (BMT). Amphotericin-B is frequently given to these patients, both therapeutically and prophylactically, and has been described to have a negative impact on the results of platelet transfusions. We conducted a prospective study of the effect of amphotericin-B on transfused platelet recovery and survival in 81 BMT or acute leukaemia patients. One hundred and ninety-five platelet transfusions administered to 81 consecutive patients were analysed. The platelets were transfused 2 h after the completion of amphotericin-B. Using this schedule resulted in no effect of amphotericin-B on platelet recovery or survival, although platelet increments were modestly depressed in patients receiving high- vs. low-dose amphotericin-B. We conclude that the timing of amphotericin-B infusion be evaluated in patients demonstrating poor platelet recovery and survival. Transfusing platelets at least 2 h after the completion of amphotericin-B decreases the detrimental effect of this antifungal agent on transfused platelet recovery and survival.

Amphotericin B↗
PubMed2003

Triggers for prophylactic use of platelet transfusions and optimal platelet dosing in thrombocytopenic dogs and cats.

Prophylactic platelet transfusions are frequently given to human patients with hypoproliferative thrombocytopenia. For several decades, the most common transfusion trigger was 20,000/microL, but the trend is now to use 10,000/microL in the absence of other risk factors for bleeding. This trigger seems to reduce the number of transfusions without increasing the risk of severe bleeding. Most studies involved in establishing platelet transfusion policies have involved patients with acute leukemia, with fewer studies involving patients undergoing hematopoietic stem cell transplantation or aggressive chemotherapy for other cancers and patients with aplastic anemia. In the presence of other risk factors for spontaneous bleeding, 20,000/microL is still considered an appropriate trigger. The trigger for prophylactic transfusion before surgery has not undergone the same recent scrutiny as has the trigger for spontaneous bleeding. The recommendation remains to raise the platelet count to 50,000 to 100,000/microL if possible, although it is recognized that surgery and other invasive procedures have been performed at lower platelet counts without major bleeding. Prophylactic transfusion is not used in disorders of platelet consumption and destruction to prevent spontaneous bleeding but is used before surgery. Because of the comparative lack of experience with platelet transfusion in veterinary medicine, it is difficult to make generalizations for dogs and cats. Using the guidelines established for therapeutic and prophylactic transfusion of human patients is a reasonable starting point, however. A therapeutic transfusion policy is suggested in the veterinary setting provided that the patient can be closely observed for critical bleeding and a prompt transfusion can be given. This policy should ultimately reduce the overall number of platelet transfusions given to hospital patients. If an animal cannot be closely observed or the ability to transfuse on demand is limited, prophylactic transfusion is recommended. The triggers for initiating a platelet transfusion in dogs are extrapolated from human data; these values are lower by 50% for cats. Because of the imprecision of platelet counting at low values, platelet counts must always be interpreted in conjunction with clinical signs of hemorrhage. If platelet-rich plasma or platelet concentrate is available, a dose of 1 platelet unit per 10 kg is recommended, although resources may dictate a smaller dose. This will raise the recipient platelet count by a maximum of about 40,000/microL. Assuming a trigger of 10,000/microL, a transfusion will probably be required approximately every 3 days. It must be remembered that the frequency of platelet transfusions may be greater in the presence of factors accelerating platelet loss or destruction. If fresh whole blood is used, a rule of thumb is to transfuse 10 mL/kg, which will raise the recipient platelet count by a maximum of approximately 10,000/microL. Daily transfusions or transfusions every other day will probably be required.

Animals↗
PubMed1994

Clinical aspects of platelet transfusion therapy.

Platelet transfusions are established as effective treatment for thrombocytopenic bleeding. However, the indications for prophylactic platelet transfusions are being reconsidered because of the greatly increased demand for platelet concentrates. Platelet refractoriness is the main clinical problem associated with repeated platelet transfusions. This is most frequently due to HLA alloimmunisation or non-immune platelet consumption associated with clinical factors such as septicaemia. The initial management of refractory alloimmunised patients is to use HLA-matched platelet transfusions. If there is no improvement with HLA-matched platelet transfusions, platelet crossmatching may identify the cause of the problem and help with the selection of compatible donors. Other measures used to improve responses to platelet transfusions are usually ineffective. There has been considerable interest in methods to prevent HLA alloimmunisation and platelet refractoriness and particularly in leucocyte depletion of blood components. The use of leucocyte-depleted blood components has other benefits for multitransfused patients, but further studies are needed before the routine use of leucocyte-depleted blood components can be recommended for patients likely to receive repeated platelet transfusions.

Antigens, Human Platelet↗