Transfusion最新文献

The implementation of the use of low titre group O whole blood in the North Estonia Medical Centre took place in a little more than 2 years. It began with the creation of a low-titer O+ male donor registry, included a pilot project with a limited number of patients, validation of whole blood as a new product, and also required a change in the Estonian law. Today, whole blood is in routine use in emergency patients of both sexes and all ages with life-threatening bleeding. Among the indications, gastro intestinal bleeding comes first, followed by acute blood loss associated with trauma. Whole blood is also included in the massive transfusion protocol.

Introduction: The rate of D-alloimmunization amongst RhD-negative recipients of RhD-positive red blood cell (RBC) transfusions is not certain. Recipients with a short duration between the index RhD-positive transfusion and the last antibody detection test that did not show anti-D might become D-alloimmunized in the future. A regression model was developed to predict how often such patients might develop D-alloimmunization in the future to help account for the immunohematological uncertainty that accompanies having short serological follow up periods.

Methods: Using the published literature on recipients who were intentionally transfused with RhD-positive RBCs and serially followed with antibody screens, as well as unpublished datasets, a regression model was constructed to demonstrate the timing of D-alloimmunization for recipients who became D-alloimmunized within 6 months following the index transfusion. The model was then applied to a series of RhD-negative hospitalized recipients of at least one unit of RhD-positive RBCs who did not become D-alloimmunized but who had fewer than 6 months of serological follow up to weight their contribution to the D-alloimmunization rate.

Results: Overall, the rate of D-alloimmunization was 21/105 (20.0%). There were 39 patients whose last documented antibody screen was performed between 14 days and 6 months after the index RhD-positive transfusion, and these patients were entered into the weighted model. After applying the model, the D-alloimmunization rate rose to 26.3%.

Conclusion: Using a weighted model can help reduce the immunohematological uncertainty that accompanies the inclusion of patients with relatively short serological follow up in studies of RBC alloimmunization.

Background: As low titer group O whole blood (LTOWB) increases in popularity, blood centers are finding innovative ways of maintaining the supply. One potential way is collecting LTOWB from parous female donors without testing for HLA antibodies. This in silico simulation predicted the risk of an LTOWB unit containing an HLA antibody and the subsequent risk for an HLA-incompatible transfusion.

Methods: An LTOWB blood bank with 1 million units was simulated consisting of male, nulliparous, and parous female donors. The proportion of each donor type was modeled after the sex distribution at US blood centers. The parity of female donors was calculated based on the average number of live births per female depending on her age. HLA-alloimmunization risk was determined by her parity status. The HLA haplotypes of the simulated recipients were derived from the 100 most common HLA haplotypes in the US National Marrow Registry Program database. The proportion of different race/ethnic groups in the US was used to simulate 100,000 LTOWB recipients to whom between 1 and 10 units were administered.

Results: Overall, the risk of an LTOWB unit containing at least one HLA antibody was 12.2% and the rate of receiving an HLA-incompatible unit was 21.3%. The risk of receiving an HLA-incompatible unit rose from 4.8% after receipt of one unit to 36.5% after 10 units.

Conclusion: Blood collectors and hospitals should evaluate the potential TRALI risk against the benefit of a potentially expanded inventory of LTOWB before collecting plasma-containing products from non-HLA-tested parous female donors.

Background: Misoprostol, a synthetic prostaglandin E1 analogue, is widely used in obstetrics for its uterotonic properties. It is known to cause thermogenic side effects, a fact well-recognized in obstetrics but less familiar in transfusion medicine.

Study design and methods: Data were collected through chart review, including temperature recordings, serologic findings, and blood culture results.

Results: This case report describes a postpartum temperature spike to 39.2°C in a G1P0 female who received a red cell transfusion shortly after administration of misoprostol. Serologic workup for transfusion reaction showed no abnormalities, and blood cultures of both the patient and donor were negative for growth. Febrile nonhemolytic transfusion reaction (FNHTR) remained in the differential, however, the fever was attributed to misoprostol's thermogenic effect rather than a transfusion reaction.

Discussion: Increased awareness of misoprostol's thermogenic effects in transfusion medicine may improve differential diagnosis, reduce unnecessary testing, and enhance patient satisfaction by avoiding unwarranted concerns regarding transfusion reactions.

Background: Non-refrigerated whole blood can be used for bleeding emergencies when cold-stored whole blood is unavailable. Storage time in room temperature is usually limited to 24 h although there is little evidence supporting this practice. We studied the quality of whole blood stored in room temperature for 5 days to investigate the effects of prolonged storage time.

Study design and methods: Non-leukoreduced whole blood in CPDA-1 from 10 group O or A RhD positive male donors was stored in +22°C for 120 h. Samples were taken daily to assess blood cultures, blood count and metabolic parameters. Platelet function and blood coagulation were evaluated with multiple electrode aggregometry, viscoelastic tests (sonorheometry and rotational thromboelastometry), thrombin generation assay and measurements of individual clotting factors.

Results: Blood cell counts remained stable during storage. Metabolic changes were similar to those previously reported in cold-stored blood products. Most coagulation factor levels, including FVIII, decreased during storage but remained within physiological range. Thrombin generation remained mostly intact during storage. In viscoelastic tests, clotting times prolonged, but clot strength remained stable. Platelet function in multiple electrode aggregometry impaired along with storage. No bacterial growth was detected in any sample.

Conclusion: Whole blood stored in room temperature for 5 days seems bacteriologically safe and retains most of its metabolic and hemostatic function. These results suggest that whole blood stored in room temperature may be usable for longer than the currently recommended 24 h.

Background: Early resuscitation is based on platelet-poor components such as red blood cells and plasma (RBC + P), contributing to platelet dilution and worsening of trauma-induced coagulopathy (TIC). We aimed to compare the ability of cold-stored whole blood (WB) versus RBC + P as a single component to correct TIC.

Study design and methods: Blood samples were collected on admission from trauma patients who required activation of the major hemorrhage protocol at a single UK major trauma center in 2021/2022. Samples were spiked ex vivo with volumes equivalent to two, four, or eight units of WB or RBC + P stored for a maximum of 2 weeks. Thromboelastometry, platelet counting, and multiple electrode aggregometry (MEA) were performed.

Results: Samples from 20 adult trauma patients were analyzed. Median age was 32 years (27-42), 89% were male, 70% had platelet dysfunction (tissue factor-activated ROTEM [EXTEM]-tissue factor-activated ROTEM with cytochalasin D [FIBTEM] clot amplitude at 5 min [A5] ≤ 30 mm), 65% were coagulopathic (EXTEM A5 ≤ 40 mm), and 42% died. EXTEM-FIBTEM A5 was higher following spiking with WB than RBC + P (33 mm, 26-33, vs. 27 mm, 24-30, p < .001). WB-spiking corrected platelet dysfunction in 2 patient samples out of 20, whereas RBC + P increased the frequency of platelet dysfunction (1/20 sample) and TIC (4/20 samples). RBC + P was associated with a dose-dependent deterioration in rotational thromboelastometry (ROTEM) clot strength and dynamics, platelet count, and aggregation in response to multiple agonists compared with WB-spiking, which maintained or partially corrected these abnormalities.

Conclusion: Compared with RBC + P, WB better preserves ex vivo platelet-related ROTEM parameters, platelet count, and aggregation, but does not fully correct these common derangements of TIC.

Background: IgG against alloantigens on transfused RBC can lead to antibody-mediated immune enhancement (AMIE). AMIE has properties not found in other forms of alloimmunization, including rapid clearance of RBCs, a requirement for Fc-gamma receptors on dendritic cells, and no dependence on IFNAR. A spleen is required for alloimmunization to transfused RBCs under normal conditions but its role in AMIE has not been assessed.

Study design and methods: Mice with surgical splenectomy or sham surgery were infused with monoclonal IgG against model antigens (HOD or KEL) followed by a transfusion of respective transgenic RBCs. Antibody binding to transfused RBCs, antigen-modulation, and RBC clearance were assessed by flow cytometry. IgM and IgG to the HOD and KEL alloantigens were quantified by flow cytometry-based crossmatch.

Results: IgG to either HOD or KEL caused brisk clearance of RBCs with almost complete antigen modulation at 24 h and a strong enhancement of both IgM and IgG in sham-operated animals. In splenectomized animals, AMIE was eliminated; antigen-modulation occurred but with decreased kinetics and magnitude; and RBC clearance was the same as in sham animals.

Conclusions: The current study extends the role of spleen as a general requirement for all known pathways of RBC alloimmunization studied thus far. However, the dissociation of clearance and antigen-modulation from AMIE shown in the current study raises the possibility that antigen-modulation and AMIE are correlated due to a confounding common cause (i.e., IgG binding RBCs).

Background: We investigated whether frequent apheresis donors have altered risk of bone fractures, and prescription of osteoporosis medicine//s due to their repeated exposure to citrate anticoagulant.

Methods: We used the Sax Institute's 45 and Up Study data linked with blood donation and other health-related datasets. We used a "5-year qualification period" method to identify active donors who donated at least one (any type) donation in the first and fifth year of the "qualification period." We categorized donors into 0, 1-29, and 30+ donation groups based on the number of apheresis donations made during the qualification period. We then compared the risk of bone fractures, and initiation of osteoporosis medicine/s in the years following the "qualification period" between the groups, using Cox proportional-hazards models including several potential confounders.

Results: A total of 7369 donors met the qualification criteria, of which 2033 (27.6%) made at least one apheresis donation. Of those donating by apheresis, 381 (18.7%) also made platelet as well as plasma donation, and rest donated plasma only. The median follow-up time for overall bone fractures was 5.49 years/per-donor (Q1-Q3, 5.27-5.95). In the fully adjusted models, compared to donors not making any apheresis donation, the hazard ratio for all-cause bone fractures, osteoporotic bone fractures, and initiation of osteoporosis medicine/s in donors donating 30+ apheresis donations was 0.96 (95% CI: 0.58-1.60), 0.73 (95% CI: 0.29-1.82), and 1.09 (95% CI: 0.66-1.81), respectively.

Conclusions: We did not observe a statistically significant change in risk of bone fractures, and initiation of osteoporosis medicine/s in frequent apheresis donors predominantly consisting of plasmapheresis donors.