The safety of COVID-19 convalescent plasma donation: A multi-institutional donor hemovigilance study.

BACKGROUND: Although the safety and therapeutic efficacy of COVID-19 convalescent plasma (CCP) has been extensively evaluated, the safety of CCP donation has not been explored in a multi-institutional context. STUDY DESIGN AND METHODS: Nine blood collection organizations (BCOs) participated in a multi-institutional donor hemovigilance effort to assess the safety of CCP donation. Donor adverse events (DAEs) were defined according to the Standard for Surveillance of Complications Related to Blood Donation, and severity was assessed using the severity grading tool. Multivariate analysis was performed to determine attributes associated with DAE severity. RESULTS: The overall DAE rate was 37.7 per 1000 donations. Repeat apheresis and apheresis-naïve donors experienced adverse event rates of 19.9 and 49.8 per 1000 donations, respectively. Female donors contributed 51.9% of CCP donations with a DAE rate of 49.4 per 1000 donations. The DAE rate for male donors was 27.4 per 1000 donations. Vasovagal reactions accounted for over half of all reported DAEs (51.1%). After adjustment, volume of CCP donated was associated with vasovagal reaction severity (odds ratio [OR] 6.5, 95% confidence interval [CI] 2.5-17.1). Donor age and donation history were also associated with DAE severity. Considerable differences in DAE types and rates were observed across the participating BCOs despite the use of standardized hemovigilance definitions. CONCLUSION: The safety of CCP donation appears comparable to that of conventional apheresis plasma donation with similar associated risk factors for DAE types and severity.

Complement activating ABO anti-A IgM/IgG act synergistically to cause erythrophagocytosis: implications among minor ABO incompatible transfusions.

BACKGROUND: Typically minor ABO incompatible platelet products are transfused without any incident, yet serious hemolytic transfusion reactions occur. To mitigate these events, ABO 'low titer' products are used for minor ABO incompatible transfusions. We sought to understand the role of IgM/IgG and complement activation by anti-A on extravascular hemolysis. METHODS: Samples evaluated included (i) Group O plasma from a blood donor whose apheresis platelet product resulted in an extravascular transfusion reaction, (ii) Group O plasma from 12 healthy donors with matching titers that activated complement (N = 6) or not (N = 6), and (iii) Group O sera from 10 patients with anti-A hemolysin activity. A flow cytometric monocyte erythrophagocytosis assay was developed using monocytes isolated by immunomagnetic CD14-positive selection from ACD whole blood of healthy donors. Monocytes were frozen at - 80 °C in 10% dimethyl sulfoxide/FBS and then thawed/reconstituted on the day of use. Monocytes were co-incubated with anti-A-sensitized fluorescently-labeled Group A1 + RBCs with and without fresh Group A serum as a source of complement C3, and erythrophagocytosis was analyzed by flow cytometry. The dependency of IgM/IgG anti-A and complement C3 activation for RBC erythrophagocytosis was studied. Anti-A IgG subclass specificities were examined for specific samples. RESULTS: The plasma and sera had variable direct agglutinating (IgM) and indirect (IgG) titers. None of 12 selected samples showed monocyte-dependent erythrophagocytosis with or without complement activation. The donor sample causing a hemolytic transfusion reaction and 2 of the 10 patient sera with hemolysin activity showed significant erythrophagocytosis (> 10%) only when complement C3 was activated. The single donor plasma and two sera demonstrating significant erythrophagocytosis had high IgM (≥ 128) and IgG titers (> 1024). The donor plasma anti-A was IgG1, while the patient sera were an IgG3 and an IgG1 plus IgG2. CONCLUSION: High anti-A IgM/IgG titers act synergistically to cause significant monocyte erythrophagocytosis by activating complement C3, thus engaging both Fcγ- and CR1-receptors.

Use of a cloud-based search engine of a centralized donor database to identify historical antigen-negative units in hospital inventories.

BACKGROUND: The provision of units with antigen-negative attributes is required for alloimmunized transfusion recipients and to avoid alloimmunization among patients on chronic transfusion support. Recent evidence confirms that the demand for antigen-typed units is increasing. STUDY DESIGN AND METHODS: A cloud-based search engine was designed by the blood center to find antigen-negative units. The service provided access to historical antigen information for units in hospital inventories. The hospital transfusion service was required to confirm the antigen phenotype. The results of 16 hospitals' use over 5 years were analyzed to determine trends and value of the service. The time commitment of the cloud-based query was compared to the hospital performing manual phenotyping with an outcome of at least one unit found with the desired antigen-negative attribute(s). RESULTS: Hospitals were located between 4 miles and 200 miles away from the blood center. A total of 6,081 queries were submitted over the 5 years, with an overall 50% success rate of finding at least one unit. Single antigen queries accounted for 67% of total searches, with two antigen queries and three or more antigen queries accounting for 24% and 9% of the units found, respectively. The cloud-based antigen query was most efficient for combined antigen frequencies <0.5 for two or more antigen-negative attributes. CONCLUSION: A cloud-based search engine provides hospitals with access to historical antigen information housed at the blood center. Future refinements may consider regulatory submission of a process to provide confirmed historical information through this cloud-based program.

NT-proBNP levels in the identification and classification of pulmonary transfusion reactions.

BACKGROUND: Consensus definitions for transfusion-related acute lung injury (TRALI) and transfusion-associated circulatory overload (TACO) have recently been revised; however, pulmonary transfusion reactions remain difficult to diagnose. We hypothesized that N-terminal pro-brain natriuretic peptide (NT-proBNP) levels could have utility in the identification and classification of pulmonary transfusion reactions. STUDY DESIGN AND METHODS: We performed a secondary analysis of a case-control study of pulmonary transfusion reactions at four academic hospitals. We evaluated clinical data and measured NT-proBNP levels prior to and following transfusion in patients with TACO (n = 160), transfused acute respiratory distress syndrome (ARDS) [n = 51], TRALI [n = 12], TACO/TRALI [n = 7], and controls [n = 335]. We used Wilcoxon Rank-Sum tests to compare NT-proBNP levels, and classification and regression tree (CART) algorithms to produce a ranking of covariates in order of relative importance for differentiating TACO from transfused controls. RESULTS: Pre-transfusion NT-proBNP levels were elevated in cases of transfused ARDS and TACO (both P < .001) but not TRALI (P = .31) or TACO/TRALI (P = .23) compared to transfused controls. Pre-transfusion NT-proBNP levels were higher in cases of transfused ARDS or TRALI with a diagnosis of sepsis compared to those without (P < .05 for both). CART analyses resulted in similar differentiation of patients with TACO from transfused controls for models utilizing either NT-proBNP levels (AUC 0.83) or echocardiogram results (AUC 0.80). CONCLUSIONS: NT-proBNP levels may have utility in the classification of pulmonary transfusion reactions. Prospective studies are needed to test the predictive utility of pre-transfusion NT-proBNP in conjunction with other clinical factors in identifying patients at risk of pulmonary transfusion reactions.

Use of a rapid electronic survey methodology to estimate blood donors' potential exposure to emerging infectious diseases: Application of a statistically representative sampling methodology to assess risk in US blood centers.

Risk assessments of transfusion-transmitted emerging infectious diseases (EIDs) are complicated by the fact that blood donors' demographics and behaviors can be different from the general population. Therefore, when assessing potential blood donor exposure to EIDs, the use of general population characteristics, such as U.S. travel statistics, may invoke uncertainties that result in inaccurate estimates of blood donor exposure. This may, in turn, lead to the creation of donor deferral policies that do not match actual risk. STUDY DESIGN AND METHODS: This article reports on the development of a system to rapidly assess EID risks for a nationally representative portion of the U.S. blood donor population. To assess the effectiveness of this system, a test survey was developed and deployed to a statistically representative sample frame of blood donors from five blood collecting organizations. Donors were directed to an online survey to ascertain their recent travel and potential exposure to Middle East respiratory syndrome coronavirus (MERS-CoV). RESULTS: A total of 7128 responses were received from 54 256 invitations. The age-adjusted estimated total number of blood donors potentially exposed to MERS-CoV was approximately 15 640 blood donors compared to a lower U.S. general population-based estimate of 9610 blood donors. CONCLUSION: The structured donor demographic sample-based data provided an assessment of blood donors' potential exposure to an emerging pathogen that was 63% larger than the U.S. population-based estimate. This illustrates the need for tailored blood donor-based EID risk assessments that provide more specific demographic risk intelligence and can inform appropriate regulatory decision making.

The evanescence and persistence of RBC alloantibodies in blood donors.

BACKGROUND: Blood donors represent a healthy population, whose red blood cell (RBC) alloantibody persistence or evanescence kinetics may differ from those of immunocompromised patients. A better understanding of the biologic factors impacting antibody persistence is warranted, as the presence of alloantibodies may impact donor health and the fate of the donated blood product. METHODS: Donor/donation data collected from four US blood centers from 2012 to 2016 as part of the Recipient Epidemiology and Donor Evaluation Study-III (REDS-III) were analyzed. Clinically significant antibodies from blood donors with more than one donation who underwent at least one follow-up antibody screen after the initial antibody identification were included. Of 632,378 blood donors, 481 (128 males and 353 females) fit inclusion criteria. RESULTS: Antibody screens detected 562 alloantibodies, with 368 of 562 (65%) of antibodies being persistently detected and with 194 of 562 (35%) becoming evanescent. Factors associated with antibody persistence included antibody specificity, detection at the first donation, reported history of transfusion, and detection of multiple antibodies concurrently. Anti-D, C, and Fya were most likely to persist, while anti-M, Jka , and S were most frequently evanescent. CONCLUSIONS: These data provide insight into variables impacting the duration of antibody detection, and they may also influence blood donor center policies regarding donor recruitment/acceptance.

Massive transfusion associated with a hemolytic transfusion reaction: necessary precautions for prevention.

CASE REPORT: A 45-year-old male presented in severe hypovolemic shock after a thoracoabdominal gunshot wound. The massive transfusion protocol (MTP) was activated and the patient was taken to the operating room. His major injuries included liver, small bowel, and right common iliac vein. Hemorrhage was stopped and a damage control laparotomy was completed. He received a total of 113 blood products. During his postoperative course he received a group B blood transfusion on Hospital Days 2 and 7 based on incorrect blood typing late in his massive transfusion and repeat testing on Day 4. RESULTS: He succumbed to multiple organ failure on Day 8. MTPs are standard in most trauma centers during which universal donor red blood cells are initially used. As hemorrhage is controlled, the patient undergoes a complete type and cross according to blood banking protocols. These typing results are used to continue transfusions once the MTP is no longer needed. In contacting other blood banks servicing Level I trauma centers, the policy of when to switch from universal donor blood to crossmatched blood is variable. CONCLUSION: Our case illustrates a potential blood typing problem that had a disastrous outcome. We identified changes in policy that will make MTPs safer.

Prevalence and risk factors for RBC alloantibodies in blood donors in the Recipient Epidemiology and Donor Evaluation Study-III (REDS-III).

BACKGROUND: Little information exists on red blood cell (RBC) alloimmunization in healthy US blood donors, despite the potential significance for donors themselves, blood recipients, and the blood center. STUDY DESIGN AND METHODS: Donor/donation data were sourced from the Recipient Epidemiology and Donor Evaluation Study-III, which contains information from four US blood centers during 2012 through 2016. Multivariable logistic regression was used to assess prevalence of positive antibody screen by donor demographics, blood type, parity, and transfusion history. RESULTS: More than 2 million units were collected from 632,378 donors, with 0.51% of donations antibody screen positive and 0.77% of donors having at least one positive antibody screen. The most common antibody specificities were D (26.4%), E (23.8%), and K (21.6%). Regression analysis indicated that increasing age, female sex, D-negative status, and history of transfusion and pregnancy were positively associated with a positive antibody screen. Prior transfusion history was most strongly associated with a positive antibody screen, with donors reporting a prior transfusion having a higher adjusted odds ratio (3.9) of having a positive antibody screen compared to donors reporting prior pregnancy (adjusted odds ratio, 2.0). Though transfusion was a more potent immune stimulus for RBC alloantibody formation than pregnancy, the sheer number of previously pregnant donors contributed to pregnancy being a risk factor for the majority of clinically significant RBC alloantibodies detected in females. CONCLUSION: These findings on prevalence of and risk factors for RBC antibodies may have implications for future medical care of donors and for operations at blood centers.

Contemporary Risk Factors and Outcomes of Transfusion-Associated Circulatory Overload.

OBJECTIVES: Transfusion-associated circulatory overload is characterized by hydrostatic pulmonary edema following blood transfusion. Restrictive transfusion practice may affect the occurrence and severity of transfusion-associated circulatory overload in critically ill patients. We sought to examine contemporary risk factors and outcomes for transfusion-associated circulatory overload. DESIGN: Case-control study. SETTING: Four tertiary care hospitals. PATIENTS: We prospectively enrolled 200 patients with transfusion-associated circulatory overload identified by active surveillance and 405 controls matched by transfusion intensity. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Among 20,845 transfused patients who received 128,263 blood components from May 2015 until July 2016, transfusion-associated circulatory overload incidence was one case per 100 transfused patients. In addition to cardiovascular comorbidities, multivariable analysis identified the following independent predictors of transfusion-associated circulatory overload: acute kidney injury, emergency surgery, pretransfusion diuretic use, and plasma transfusion-the latter especially in females. Compared with matched controls, transfusion-associated circulatory overload cases were more likely to require mechanical ventilation (71% vs 49%; p < 0.001), experienced longer intensive care and hospital lengths of stay following transfusion, and had higher mortality (21% vs 11%; p = 0.02) even after adjustment for other potentially confounding variables. CONCLUSIONS: Despite restrictive transfusion practice, transfusion-associated circulatory overload remains a frequent complication of transfusion and is an independent risk factor for in-hospital morbidity and mortality. In addition to cardiovascular and renal risk factors, plasma transfusion was associated with transfusion-associated circulatory overload after controlling for other covariates. Additional research is needed to examine the benefit of reduced erythrocyte or plasma exposure in patients at high risk for transfusion-associated circulatory overload.

Ceftriaxone-induced drug reaction mimicking acute splenic sequestration crisis in a child with hemoglobin SC disease.

BACKGROUND: Acute splenic sequestration crisis is a complication of sickle cell disease (SCD) occurring when intrasplenic red blood cell (RBC) sickling prevents blood from leaving the spleen, causing acute splenic enlargement. Although typically seen in young children, it has been reported in older children with hemoglobin (Hb)SC disease, eventually resulting in functional asplenia. Ceftriaxone is a frequently used antibiotic of choice for children with SCD, because of its efficacy against invasive pneumococcal disease. CASE REPORT: We report a case of a 9-year-old female with HbSC disease, who had a fatal reaction after receiving a dose of ceftriaxone in the outpatient clinic for fever. Her Hb level decreased abruptly from 9.3 to 2.3 mg/dL. RBC clumps with no visible hemolysis were observed in the postreaction sample. Autopsy examination revealed marked splenomegaly with acute congestion and sickled cells in the spleen and liver. Serologic testing revealed a positive direct antiglobulin test with polyspecific antibody, anti-C3, and anti-C3d, but negative with anti-immunoglobulin G. Ceftriaxone-dependent RBC antibodies were detected in her serum and RBC eluate when tested in the presence of the drug. CONCLUSION: We report a new presentation of ceftriaxone-induced drug reaction in a patient with SCD mimicking an acute splenic sequestration crisis. Review of the literature for cases of ceftriaxone-induced drug reactions in pediatric patients revealed nine previously reported cases of ceftriaxone-induced immune hemolytic anemia in children with SCD since 1995, but none with an initial presentation suggestive of acute splenic sequestration crisis.

Practical approaches and costs for provisioning safe transfusions during anti-CD38 therapy.

BACKGROUND: Anti-CD38 therapy causes interference with both the direct and the indirect antiglobulin tests. We describe the experience from an Immunohematology Reference Laboratory and model cost options for providing safe transfusions. STUDY DESIGN AND METHODS: Phenotyping, genotyping, and antibody identification orders were retrospectively reviewed in the setting of anti-CD38 therapy. The data were used to model the added cost of transfusion support. Four approaches were evaluated: 1) thiol-treated reagent red blood cells (RRCs) in antibody investigations with K- red blood cell (RBC) transfusions, 2) patient phenotyping or 3) genotyping with antigen-matched RBC transfusions, and 4) a combination of interval thiol-treated RRC antibody investigations with genotype antigen-matched RBC transfusions. RESULTS: Sixty-two patients were identified as receiving anti-CD38 therapy. Thiol-treated RRC antibody investigations (28/62 patients) were favored over genotyping (23/62) and combination testing (11/62). Patient phenotyping failed to detect useful antigen information on eight patients: seven Fyb silencing mutations and one partial e. A thiol-treated RRC antibody investigation was the least expensive testing method for the first transfusion, but four- and five-antigen-matched RBC transfusions were equal in cost within five and 21 transfusion events, respectively. CONCLUSION: Genotyping provided a more accurate antigen status than phenotyping patient RBCs. Patients requiring long-term transfusion support benefit from antigen matching when matching less than four antigens. Ultimately, the decision to genotype or use thiol-treated RRC antibody investigations will vary for each hospital blood bank.

The first reported case of concurrent trimethoprim-sulfamethoxazole-induced immune hemolytic anemia and thrombocytopenia.

BACKGROUND: Drug-induced immune hemolytic anemia (DIIHA) and drug-induced immune thrombocytopenia (DIIT) are rare but dangerous complications of pharmacotherapy that may be underrecognized in hematopoietic stem cell transplant (HSCT) patients due to overlap of signs and symptoms with those of more common disease processes. CASE REPORT: A 61-year-old woman with NK-cell deficiency and GATA-2-associated myelodysplastic syndrome, status post-recent allogeneic HSCT (Day +58), presented with 3 days of acute-onset severe back pain, muscle cramps, and increasingly dark urine. She was found to be anemic, thrombocytopenic, and in acute renal failure. On admission, the direct antiglobulin test was positive for complement (C3) only. After careful review of her medication list, the possibility of DIIHA was raised. She had started taking trimethoprim-sulfamethoxazole (TMP-SMX) for Pneumocystis jiroveci pneumonia prophylaxis 24 days prior on a weekend dose schedule. Serologic tests on peripheral blood samples were performed using standard methods. Drug studies were performed at an immunohematology reference laboratory. RESULTS: The patient's serum showed hemolysis of donor red blood cells in the presence of TMP-SMX and also TMP-SMX-induced platelet antibodies. The patient was treated with transfusions, hemodialysis, and immunosuppressive agents. Her clinical condition improved and she was discharged after 8 days in stable condition. CONCLUSION: This case describes the first reported concurrent DIIHA and DIIT due to TMP-SMX-induced antibodies in an HSCT patient. DIIHA and DIIT can present a diagnostic challenge in the setting of intermittent medication dosing.

Demographic and epidemiologic characterization of transfusion recipients from four US regions: evidence from the REDS-III recipient database.

BACKGROUND: Blood transfusion is one of the most common medical procedures during hospitalization in the United States. To understand the benefits of transfusion while mitigating potential risks, a multicenter database containing detailed information on transfusion incidence and recipient outcomes would facilitate research. STUDY DESIGN AND METHODS: The Recipient Epidemiology and Donor Evaluation Study-III (REDS-III) program has developed a comprehensive transfusion recipient database utilizing data from hospital electronic health records at 12 participating hospitals in four geographic regions. Inpatient and outpatient data on transfusion recipients from January 1, 2013 to December 31, 2014 included patient age, sex, ethnicity, primary diagnosis, type of blood product provided, issue location, pretransfusion and post-transfusion hemoglobin (Hgb), and hospital outcomes. Transfusion incidence per encounter was calculated by blood product and various patient characteristics. RESULTS: During the 2-year study period, 80,362 (12.5%) inpatient encounters involved transfusion. Among inpatients, the most commonly transfused blood products were red blood cells (RBCs; 10.9% of encounters), followed by platelets (3.2%) and plasma (2.9%). Among patients who received transfusions, the median number of RBC units was one, the pretransfusion Hgb level was 7.6 g/dL, and the Hgb increment per unit was 1.4 g/dL. Encounter mortality increased with patient age, the number of units transfused, and the use of platelet or plasma products. The most commonly reported transfusion reaction was febrile nonhemolytic. CONCLUSION: The database contains comprehensive data regarding transfusion use and patient outcomes. The current report describes an evaluation of the first 2 years of a planned, 4-year, linked blood donor-component-recipient database, which represents a critical new resource for transfusion medicine researchers.

Incidence of transfusion reactions: a multicenter study utilizing systematic active surveillance and expert adjudication.

BACKGROUND: Prevalence estimates of the serious hazards of transfusion vary widely. We hypothesized that the current reporting infrastructure in the United States fails to capture many transfusion reactions and undertook a multicenter study using active surveillance, data review, and adjudication to test this hypothesis. STUDY DESIGN AND METHODS: A retrospective record review was completed for a random sample of 17% of all inpatient transfusion episodes over 6 months at four academic tertiary care hospitals, with an episode defined as all blood products released to a patient in 6 hours. Data were recorded by trained clinical research nurses, and serious reactions were adjudicated by a panel of transfusion medicine experts. RESULTS: Of 4857 transfusion episodes investigated, 1.1% were associated with a serious reaction. Transfusion-associated circulatory overload was the most frequent serious reaction noted, being identified in 1% of transfusion episodes. Despite clinical notes describing a potential transfusion association in 59% of these cases, only 5.1% were reported to the transfusion service. Suspected transfusion-related acute lung injury/possible transfusion-related acute lung injury, anaphylactic, and hypotensive reactions were noted in 0.08, 0.02, and 0.02% of transfusion episodes, respectively. Minor reactions, including febrile nonhemolytic and allergic, were noted in 0.62 and 0.29% of transfusion episodes, respectively, with 30 and 50% reported to the transfusion service. CONCLUSION: Underreporting of cardiopulmonary transfusion reactions is striking among academic, tertiary care hospitals. Complete and accurate reporting is essential to identify, define, establish pathogenesis, and mitigate/treat transfusion reactions. A better understanding of the failure to report may improve the accuracy of passive reporting systems.

Implementing mass-scale red cell genotyping at a blood center.

BACKGROUND: When problems with compatibility beyond ABO and D arise, currently transfusion services search their inventories and perform time-consuming serologic testing to locate antigen-negative blood. These clinically important blood group antigens can be detected reliably by red cell genotyping, which is a technology whereby DNA-based techniques are used to evaluate gene polymorphisms that determine the expression of blood group antigens. We introduced mass-scale genotyping and measured availability of genotyped blood. STUDY DESIGN AND METHODS: All non-Caucasian donors qualified for genotyping along with donors who had a history of repeat donation. Mass-scale red cell genotyping, performed on an electronic interfaced open array platform, was implemented to screen blood donors for 32 single-nucleotide polymorphisms that predicted 42 blood group antigens. Genotype screening results were confirmed by phenotyping, when needed for antigen-negative transfusion, before release of the red blood cell (RBC) unit. RESULTS: Approximately 22,000 donors were red cell genotyped within 4 months and a total of 43,066 donors in 4 years. There were 463 discordances (0.52% of 89,596 genotypes with a phenotype). Among the 307 resolved discordances, approximate equal numbers represented historical serologic or genotyping discrepancies (n = 151 and n = 156, respectively). In the final year of the study, a mean of 29% of the daily inventory had a genotype. CONCLUSIONS: Red cell genotyping of blood donors using an electronic interface created a large and stable supply of RBC units with historical genotypes. The database served the needs of antigen-negative blood requests for a large regional blood center and allowed us to abandon screening by serology.

Barriers to using molecularly typed minority red blood cell donors in support of chronically transfused adult patients with sickle cell disease.

BACKGROUND: Much effort and resources have been devoted to programs that provide transfusion support for patients with sickle cell disease (SCD). The focus of many donor programs is to prevent alloimmunization by recruiting racially matched African American donors to limit the red blood cell (RBC) antigenic differences that exist between Caucasian donors and patients with SCD. STUDY DESIGN AND METHODS: In this study, we evaluated the RBC antigen characteristics of both the recipient population with SCD and the African American donor population from 2010 to 2013. We evaluated the genotype-derived predicted antigen frequencies of the donors and compared these frequencies with those of the population supported by these units. Specific attention was given to the alloimmunization rate over the 3 years and the number of D- units provided to D+ patients. RESULTS: We recruited 6066 African American donors during the 3-year study period with 77.3% of these donors donating no more than twice. The observed genotype-derived predicted antigen frequencies were similar to the expected frequencies, and the antigen frequencies of a cohort of 54 adult patients with SCD (p > 0.05). Twelve patients (22.2%) with SCD had alloantibodies and five of these patients developed these antibodies while receiving Rh and K antigen-matched blood during the study interval. Finally, we found that 607 (37.1%) D- units were diverted to D+ patients. CONCLUSIONS: New recruitment and prevention strategies are needed to increase the pool of available antigen-matched RBCs and decrease alloimmunization risk for this patient population.

Making thawed universal donor plasma available rapidly for massively bleeding trauma patients: experience from the Pragmatic, Randomized Optimal Platelets and Plasma Ratios (PROPPR) trial.

BACKGROUND: The Pragmatic, Randomized Optimal Platelets and Plasma Ratios (PROPPR) trial was a randomized clinical trial comparing survival after transfusion of two different blood component ratios for emergency resuscitation of traumatic massive hemorrhage. Transfusion services supporting the study were expected to provide thawed plasma, platelets, and red blood cells within 10 minutes of request. STUDY DESIGN AND METHODS: At the 12 Level 1 trauma centers participating in PROPPR, blood components transfused and delivery times were tabulated, with a focus on universal donor (UD) plasma management. The adequacy of site plans was assessed by comparing the bedside blood availability times to study goals and the new American College of Surgeons guidelines. RESULTS: Eleven of 12 sites were able to consistently deliver 6 units of thawed UD plasma to their trauma-receiving unit within 10 minutes and 12 units in 20 minutes. Three sites used blood group A plasma instead of AB for massive transfusion without complications. Approximately 4700 units of plasma were given to the 680 patients enrolled in the trial. No site experienced shortages of AB plasma that limited enrollment. Two of 12 sites reported wastage of thawed AB plasma approaching 25% of AB plasma prepared. CONCLUSION: Delivering UD plasma to massively hemorrhaging patients was accomplished consistently and rapidly and without excessive wastage in high-volume trauma centers. The American College of Surgeons Trauma Quality Improvement Program guidelines for massive transfusion protocol UD plasma availability are practicable in large academic trauma centers. Use of group A plasma in trauma resuscitation needs further study.

Clinical and reference lab characteristics of patients with suspected direct antiglobulin test (DAT)-negative immune hemolytic anemia.

Clinical evidence of warm autoimmune hemolytic anemia is present in 1 percent to 10 percent of patients whose direct antiglobulin test (DAT) is negative. The clinical underpinnings associated with DAT-negative immune hemolysis are poorly understood, and the current study aimed to further define the clinical characteristics associated with this form of anemia. A 19-question survey, requesting clinical information about each patient, was retrospectively mailed to all referring labs that had sent patient samples for an enhanced DAT evaluation from January 2011 through June 2013. An enhanced DAT evaluation involved a standard DAT and DATs performed using gel, polyethylene glycol, and 4°C low-ionic strength saline wash. We obtained detailed clinical information from 57 patients with an enhanced DAT investigation. Eighteen of these 57 patients (31.6%) were found to have a positive DAT, 11 (19.3%) of which were found to have a positive enhanced DAT (2 were positive by enhanced methods methods and negative by standard methods). The reported mean nadir hemoglobin for all 57 patients was 7.8% g/dL (range 3.2-12.7), and lactate dehydrogenase was 827.8 U/L (range 136-6917). Thirty-seven (18.1%) presented with a haptoglobin <10 mg/dL, and 21 (48.8%) reported spherocytes on peripheral smear. About half of the respondents reported using steroids as treatment for the anemia, and 4 of the 18 DAT-positive respondents (23.5%) changed their treatment plan because of the reference laboratory results. One patient died as a result of the reported hemolytic anemia (2.0%). We conclude that immune hemolysis detected by enhanced DAT methods is relatively common, and enhanced DAT methods are valuable tools in the diagnosis and management of patients with DAT-negative hemolytic anemia.

Trends in red blood cell transfusion and 30-day mortality among hospitalized patients.

BACKGROUND: Blood conservation strategies have been shown to be effective in decreasing red blood cell (RBC) utilization in specific patient groups. However, few data exist describing the extent of RBC transfusion reduction or their impact on transfusion practice and mortality in a diverse inpatient population. STUDY DESIGN AND METHODS: We conducted a retrospective cohort study using comprehensive electronic medical record data from 21 medical facilities in Kaiser Permanente Northern California. We examined unadjusted and risk-adjusted RBC transfusion and 30-day mortality coincident with implementation of RBC conservation strategies. RESULTS: The inpatient study cohort included 391,958 patients who experienced 685,753 hospitalizations. From 2009 to 2013, the incidence of RBC transfusion decreased from 14.0% to 10.8% of hospitalizations; this change coincided with a decline in pretransfusion hemoglobin (Hb) levels from 8.1 to 7.6 g/dL. Decreased RBC utilization affected broad groups of admission diagnoses and was most pronounced in patients with a nadir Hb level between 8 and 9 g/dL (n = 73,057; 50.8% to 19.3%). During the study period, the standard deviation of risk-adjusted RBC transfusion incidence across hospitals decreased by 44% (p < 0.001). Thirty-day mortality did not change significantly with declines in RBC utilization in patient groups previously studied in clinical trials nor in other subgroups. CONCLUSIONS: After the implementation of blood conservation strategies, RBC transfusion incidence and pretransfusion Hb levels decreased broadly across medical and surgical patients. Variation in RBC transfusion incidence across hospitals decreased from 2010 to 2013. Consistent with clinical trial data, more restrictive transfusion practice did not appear to impact 30-day mortality.

A multicenter evaluation of a new therapeutic plasma exchange procedure.

BACKGROUND: The AMICUS (Fenwal, Inc.) was cleared in the United States for platelet (PLT) and plasma collection in 1996 with subsequent clearances for the collection of other blood products. Although not previously used for therapeutic plasma exchange (TPE), new disposables, software, and hardware were developed to enable TPE on the AMICUS. STUDY DESIGN AND METHODS: A multicenter, randomized, nonblinded, crossover paired treatment protocol was performed. Thirty patients with orders for at least two TPE procedures were randomly assigned to the AMICUS or the COBE Spectra (TerumoBCT) for the first treatment. Each patient was crossed over to the other device using the same procedure settings from the first procedure. The primary objective compared efficiency of plasma removal (EPR) with secondary objectives of comparing PLT and hemoglobin (Hb) waste plasma content, coagulation factor and complement activation, fluid balance tracking accuracy, procedure length, and adverse events. RESULTS: The EPR for the AMICUS (81.9 ± 7.62%) was superior to that of the COBE Spectra (75.2 ± 6.29%; p = 0.00001). The AMICUS also demonstrated statistically higher fluid balance accuracy (99.84%) compared to that of the COBE Spectra (98.83%; p < 0.0001) and a statistically shorter procedure time (103.9 ± 30.8 vs. 110.5 ± 27.1 min, p < 0.001). No significant differences with regard to PLT and Hb content in the waste plasma, change in patient PLT count, or changes in markers of coagulation and complement cascade activation were seen. Frequency and severity of adverse reactions were similar. CONCLUSION: The AMICUS separator can effectively perform TPE. The AMICUS demonstrated superior plasma removal efficiency compared to the COBE Spectra with no evidence of significant differences in PLT removal, hemolysis, and coagulation or complement activation.