Post-Reconstitution Hemostatic Stability Profiles of Canadian and German Freeze-Dried Plasma.

Despite the importance of the hemostatic properties of reconstituted freeze-dried plasma (FDP) for trauma resuscitation, few studies have been conducted to determine its post-reconstitution hemostatic stability. This study aimed to assess the short- (≤24 h) and long-term (≥168 h) hemostatic stabilities of Canadian and German freeze-dried plasma (CFDP and LyoPlas) after reconstitution and storage under different conditions. Post-reconstitution hemostatic profiles were determined using rotational thromboelastometry (ROTEM) and a Stago analyzer, as both are widely used as standard methods for assessing the quality of plasma. When compared to the initial reconstituted CFDP, there were no changes in ROTEM measurements for INTEM maximum clot firmness (MCF), EXTEM clotting time (CT) and MCF, and Stago measurements for prothrombin time (PT), partial thromboplastin time (PTT), D-dimer concentration, plasminogen, and protein C activities after storage at 4 °C for 24 h and room temperature (RT) (22-25 °C) for 4 h. However, an increase in INTEM CT and decreases in fibrinogen concentration, factors V and VIII, and protein S activities were observed after storage at 4 °C for 24 h, while an increase in factor V and decreases in antithrombin and protein S activities were seen after storage at RT for 4 h. Evaluation of the long-term stability of reconstituted LyoPlas showed decreased stability in both global and specific hemostatic profiles with increasing storage temperatures, particularly at 35 °C, where progressive changes in CT and MCF, PT, PTT, fibrinogen concentration, factor V, antithrombin, protein C, and protein S activities were seen even after storage for 4 h. We confirmed the short-term stability of CFDP in global hemostatic properties after reconstitution and storage at RT, consistent with the shelf life of reconstituted LyoPlas. The long-term stability analyses suggest that the post-reconstitution hemostatic stability of FDP products would decrease over time with increasing storage temperature, with a significant loss of hemostatic functions at 35 °C compared to 22 °C or below. Therefore, the shelf life of reconstituted FDP should be recommended according to the storage temperature.

Evaluation of the performance of multiple immunoassay diagnostic platforms on the National Microbiology Laboratory SARS-CoV-2 National Serology Panel.

BACKGROUND: Serological assays designed to detect SARS-CoV-2 antibodies are being used in serological surveys and other specialized applications. As a result, and to ensure that the outcomes of serological testing meet high quality standards, evaluations are required to assess the performance of these assays and the proficiency of laboratories performing them. METHODS: A panel of 60 plasma/serum samples from blood donors who had reverse transcriptase-polymerase chain reaction (RT-PCR) confirmed SARS-CoV-2 infections and 21 SARS-CoV-2 negative samples were secured and distributed to interested laboratories within Canada (n = 30) and the United States (n = 1). Participating laboratories were asked to provide details on the diagnostic assays used, the platforms the assays were performed on, and the results obtained for each panel sample. Laboratories were blinded with respect to the expected outcomes. RESULTS: The performance of the different assays evaluated was excellent, with the high-throughput platforms of Roche, Ortho, and Siemens demonstrating 100% sensitivity. Most other high-throughput platforms had sensitivities of >93%, with the exception of the IgG assay using the Abbott ARCHITECT which had an average sensitivity of only 87%. The majority of the high-throughput platforms also demonstrated very good specificities (>97%). CONCLUSION: This proficiency study demonstrates that most of the SARS-CoV-2 serological assays utilized by provincial public health or hospital laboratories in Canada have acceptable sensitivity and excellent specificity.

HISTORIQUE: Les dosages sérologiques conçus pour dépister les anticorps anti-SRAS-CoV-2 sont utilisés dans les études sérologiques et d'autres applications spécialisées. Par conséquent, et pour s'assurer que leurs résultats respectent des normes de qualité, il faut procéder à des évaluations de leur performance et de la compétence des laboratoires à les effectuer. MÉTHODOLOGIE: Les chercheurs ont obtenu une batterie de 60 prélèvements de plasma et de sérum chez des donneurs dont l'amplification en chaîne par polymérase après transcription inverse (RT-PCR) avait confirmé des infections par le SRAS-CoV-2 et de 21 prélèvements dont les résultats étaient négatifs au SRAS-CoV-2 et les ont distribués aux laboratoires intéressés du Canada (n = 30) et des États-Unis (n = 1). Ils ont invité les laboratoires participants à fournir de l'information détaillée sur les dosages diagnostiques utilisés, les plateformes sur lesquelles les dosages étaient exécutés et les résultats obtenus pour chaque échantillon. Les chercheurs ont demandé aux laboratoires participants de fournir de l'information détaillée sur les dosages diagnostiques utilisés, les plateformes sur lesquelles les dosages ont été effectués, et les résultats obtenus à l'égard de chaque échantillon. Les laboratoires ont mené les études à l'insu des résultats escomptés. RÉSULTATS: Les divers dosages avaient une excellente exécution, les plateformes à haut débit de Roche, d'Ortho et de Siemens démontrant une sensibilité de 100 %. La plupart des autres plateformes à haut débit avaient des sensibilités de plus de 93 %, à l'exception des dosages des IgG faisant appel à l'analyseur ARCHITECT d'Abbott, dont la sensibilité moyenne était de seulement 87 %. La majorité des plateformes à haut débit avaient également une très bonne spécificité (plus de 97 %). CONCLUSION: La présente étude de compétence démontre que la plupart des dosages sérologiques du SRAS-CoV-2 évalués dans des laboratoires sanitaires provinciaux ou les laboratoires hospitaliers du Canada possèdent une sensibilité acceptable et une excellente spécificité.

A Qualitative Comparison of the Abbott SARS-CoV-2 IgG II Quant Assay against Commonly Used Canadian SARS-CoV-2 Enzyme Immunoassays in Blood Donor Retention Specimens, April 2020 to March 2021.

Our group has previously used laboratory and commercially developed assays to understand the IgG responses to SARS-CoV-2 antigens, including nucleocapsid (N), spike (S), and receptor binding domain (RBD), in Canadian blood donors. In this current study, we analyzed 17,428 available and previously characterized retention samples collected from April 2020 to March 2021. The analysis compared the characteristics of the Abbott SARS-CoV-2 IgG II Quant assay (Abbott anti-spike [S], Abbott, Chicago, IL) against four other IgG assays. The Abbott anti-S assay has a qualitative threshold of 50 AU/mL. The four comparator assays were the Abbott anti-nucleocapsid (N) assay and three commonly used Canadian in-house IgG enzyme-linked immunosorbent assays (ELISAs) recognizing distinct recombinant viral antigens, full-length spike glycoprotein, glycoprotein RBD, and nucleocapsid. The strongest qualitative relationship was between Sinai RBD and the Abbott anti-S assay (kappa, 0.707; standard error [SE] of kappa, 0.018; 95% confidence interval, 0.671 to 0.743). We then scored each previously characterized specimen as positive when two anti-SARS-COV-2 assays identified anti-SARS-CoV-2 IgG in the specimen. Using this composite reference standard approach, the sensitivity of the Abbott anti-S assay was 95.96% (95% confidence interval [CI], 93.27 to 97.63%). The specificity of the Abbott anti-S assay was 99.35% (95% CI, 99.21 to 99.46%). Our study provides context on the use of commonly used SARS-CoV-2 serologies in Canada and identifies how these assays qualitatively compare to newer commercial assays. Our next steps are to assess how well the Abbott anti-S assays quantitatively detect wild-type and SARS-CoV-2 variants of concern. IMPORTANCE We describe the qualitative test characteristics of the Abbott SARS-CoV-2 IgG II Quant assay against four other anti-SARS-CoV-2 IgG assays commonly used in Canada. Although there is no gold standard for identifying anti-SARS-CoV-2 seropositivity, aggregate standards can be used to assess seropositivity. In this study, we used a specimen bank of previously well-characterized specimens collected between April 2020 and March 2021. The Abbott anti-S assay showed the strongest qualitative relationship with a widely used laboratory-developed IgG assay for the SARS-CoV-2 receptor binding domain. Using the composite reference standard approach, we also showed that the Abbott anti-S assay was highly sensitive and specific. As new anti-SARS-CoV-2 assays are developed, it is important to compare their test characteristics against other assays that have been extensively used in prior research.

Freeze-dried plasma: From damage control resuscitation to coronavirus disease 2019 therapy.

BACKGROUND: Freeze-dried plasma (FDP) is a promising blood component for prehospital resuscitation given its logistic advantages over fresh frozen plasma (FFP). COVID-19 convalescent (CC) plasma has been used to treat coronavirus disease 2019 (COVID-19) patients, and its corresponding FDP has potential use during future pandemics. Therefore, we conducted the study to determine if the hemostatic and immunological properties of plasma can be retained after lyophilization. STUDY DESIGN AND METHODS: Hemostatic tests were conducted with Rotational Thromboelastometry (ROTEM) and a Stago analyzer. Anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) IgG (Immunoglobulin G) and neutralizing activity were analyzed using Meso Scale Diagnostics immunoassay kits. RESULTS: There were no differences in ROTEM parameters and Stago measurements for prothrombin time (PT), partial thromboplastin time (PTT), fibrinogen and D-dimer concentrations, and antithrombin, factor V, VIII, and protein S activities between FFP and FDP for either pre-COVID-19 or CC samples. Differences were observed in INTEM clotting time and PT and PTT when comparing reconstituted FDP stored at 4°C for 24 h or room temperature for 4 h to healthy control. Both CC-FFP and CC-FDP showed two orders of magnitude higher concentrations of IgG antibodies against SARS-CoV-2 antigens than pre-COVID-19-FFP and pre-COVID-19-FDP and healthy control. Similarly, the CC samples showed approximately 4-fold higher %-inhibition of receptor binding than the pre-COVID-19 samples. There were no differences in either the antibody levels or neutralization activity between CC-FFP and CC-FDP. DISCUSSION: We demonstrated that FDP and CC-FDP retained the same hemostatic and antibody functional activities relative to their initial plasma sources, supporting clinical evaluation of their benefits in severe trauma and COVID-19 patients.

Retention of hemostatic and immunological properties of frozen plasma and COVID-19 convalescent apheresis fresh-frozen plasma produced and freeze-dried in Canada.

BACKGROUND: Randomized clinical trial data show that early plasma transfusion may save lives among trauma patients. Supplying plasma in remote environments is logistically challenging. Freeze-dried plasma (FDP) offers a possible solution. STUDY DESIGN AND METHODS: A Terumo BCT plasma freeze-drying system was evaluated. We compared pooled frozen plasma (FP) units with derived Terumo BCT FDP (TFDP) units and pooled COVID-19 convalescent apheresis fresh-frozen plasma (CC-AFFP) with derived CC-TFDP units. Parameters measured were: coagulation factors (F) II; V; VII; VIII; IX; XI; XIII; fibrinogen; Proteins C (PC) and S (PS); antithrombin (AT); α2 -antiplasmin (α2 AP); ADAMTS13; von Willebrand Factor (vWF); thrombin-antithrombin (TAT); D-dimer; activated complement factors 3 (C3a) and 5 (C5a); pH; osmolality; prothrombin time (PT); and activated partial thromboplastin time (aPTT). Antibodies to SARS-CoV-2 in CC-AFFP and CC-TFDP units were compared by plaque reduction assays and viral protein immunoassays. RESULTS: Most parameters were unchanged in TFDP versus FP or differed ≤15%. Mean aPTT, PT, C3a, and pH were elevated 5.9%, 6.9%, 64%, and 0.28 units, respectively, versus FP. CC-TFDP showed no loss of SARS-CoV-2 neutralization titer versus CC-AFFP and no mean signal loss in most pools by viral protein immunoassays. CONCLUSION: Changes in protein activities or clotting times arising from freeze-drying were <15%. Although C3a levels in TFDP were elevated, they were less than literature values for transfusable plasma. SARS-CoV-2-neutralizing antibody titers and viral protein binding levels were largely unaffected by freeze-drying. In vitro characteristics of TFDP or CC-TFDP were comparable to their originating plasma, making future clinical studies appropriate.

Ex vivo hemostatic and immuno-inflammatory profiles of freeze-dried plasma.

BACKGROUND: Hemorrhage is a leading cause of preventable death in civilian and military trauma. Freeze-dried plasma is promising for hemostatic resuscitation in remote prehospital settings, given its potential benefits in reducing blood loss and mortality, long storage at ambient temperatures, high portability, and rapid reconstitution for transfusion in austere environments. Here we assess the ex vivo characteristics of a novel Terumo's freeze-dried plasma product (TFDP). STUDY DESIGN AND METHODS: Rotational thromboelastometry (ROTEM) tests (INTEM, EXTEM, and FIBTEM) were conducted on plasma samples at 37°C with a ROTEM delta-machine using standard reagents and procedures. The following samples were analyzed: pooled plasma to produce TFDP, TFDP reconstituted, and stored immediately at -80°C, reconstituted TFDP stored at 4°C for 24 h and room temperature (RT) for 4 h before freezing at -80°C. Analysis of plasma concentrations of selected cytokines, chemokines, and vascular molecules was performed using a multiplex immunoassay system. One-way ANOVA with post hoc tests assessed differences in hemostatic and inflammatory properties. RESULTS: No significant differences in ROTEM variables (coagulation time [CT], clot formation time, α-angle, maximum clot firmness, and lysis index 30) between the TFDP-producing plasma and reconstituted TFDP samples were observed. Compared to control plasma, reconstituted TFDP stored at 4°C for 24 h or RT for 4 h showed a longer INTEM CT. Levels of immuno-inflammatory mediators were similar between frozen plasma and TFDP. CONCLUSIONS: TFDP is equivalent to frozen plasma with respect to global hemostatic and immuno-inflammatory mediator profiles. Further investigations of TFDP in trauma-induced coagulopathy models and bleeding patients are warranted.

Glycemic benefits with adherence to testosterone therapy in men with hypogonadism and type 2 diabetes mellitus.

BACKGROUND: While previous studies have demonstrated testosterone's beneficial effects on glycemic control in men with hypogonadism and Type 2 Diabetes, the extent to which these improvements are observed based on the degree of treatment adherence has been unclear. OBJECTIVES: To evaluate the effects of long-term testosterone therapy in A1C levels in men with Type 2 Diabetes Mellitus and hypogonadism, controlling for BMI, pre-treatment A1C, and age among different testosterone therapy adherence groups. MATERIALS AND METHODS: We performed a retrospective analysis of 1737 men with diabetes and hypogonadism on testosterone therapy for 5 years of data from 2008-2018, isolating A1C, lipid panels, and BMI results for analysis. Subjects were categorized into adherence groups based on quartiles of the proportion of days covered (> 75% of days, 51-75% of days, 26-50% of days and 0-25% of days), with >75% of days covered considered adherent to therapy. RESULTS: Pre-treatment median A1C was 6.8%. Post-treatment median A1C was 7.1%. The adherent group, >75%, was the only group notable for a decrease in A1C, with a median decrease of -0.2 (p = 0.0022). BMI improvement was associated with improved post-treatment A1C (p = 0.007). When controlling for BMI, age, and pre-treatment A1C, the >75% adherence group was associated with improved post-treatment A1C (p < 0.001). DISCUSSION: When controlling for all studied variables, testosterone adherence was associated with improved post-treatment A1C. The higher the initial A1C at the initiation of therapy, the higher the potential for lowering the patient's A1C with >75% adherence. Further, all groups showed some reduction in BMI, which may indicate that testosterone therapy may affect A1C independent of weight loss. CONCLUSION: Even when controlling for improved BMI, pre-treatment A1C, and age, testosterone positively impacted glycemic control in diabetes patients with hypogonadism, with the most benefit noted in those most adherent to therapy (>75%).

Diabetes by Air, Land, and Sea: Effect of Deployments on HbA1c and BMI.

INTRODUCTION: Service members (SMs) in the United States (U.S.) Armed Forces have diabetes mellitus at a rate of 2-3%. Despite having a chronic medical condition, they have deployed to environments with limited medical support. Given the scarcity of data describing how they fare in these settings, we conducted a retrospective study analyzing the changes in glycated hemoglobin (HbA1c) and body mass index (BMI) before and after deployment. MATERIALS AND METHODS: SMs from the U.S. Army, Air Force, Navy, and Marine Corps with diabetes who deployed overseas were identified through the Military Health System (MHS) Management Analysis and Reporting Tool and the Defense Manpower Data Center. Laboratory and pharmaceutical data were obtained from the MHS Composite Health Care System and the Pharmacy Data Transaction Service, respectively. Paired t-tests were conducted to calculate changes in HbA1c and BMI before and after deployment. RESULTS: SMs with diabetes completed 11,325 deployments of greater than 90 days from 2005 to 2017. Of these, 474 (4.2%) SMs had both HbA1c and BMI measurements within 90 days prior to departure and within 90 days of return. Most (84.2%) required diabetes medications: metformin in 67.3%, sulfonylureas in 19.0%, dipeptidyl peptidase-4 inhibitors in 13.9%, and insulin in 5.5%. Most SMs deployed with an HbA1c < 7.0% (67.1%), with a mean predeployment HbA1c of 6.8%. Twenty percent deployed with an HbA1c between 7.0 and 7.9%, 7.2% deployed with an HbA1c between 8.0 and 8.9%, and 5.7% deployed with an HbA1c of 9.0% or higher. In the overall population and within each military service, there was no significant change in HbA1c before and after deployment. However, those with predeployment HbA1c < 7.0% experienced a rise in HbA1c from 6.2 to 6.5% (P < 0.001), whereas those with predeployment HbA1c values ≥7.0% experienced a decline from 8.0 to 7.5% (P < 0.001). Those who deployed between 91 and 135 days had a decline in HbA1c from 7.1 to 6.7% (P = 0.010), but no significant changes were demonstrated in those with longer deployment durations. BMI declined from 29.6 to 29.3 kg/m2 (P < 0.001), with other significant changes seen among those in the Army, Navy, and deployment durations up to 315 days. CONCLUSIONS: Most SMs had an HbA1c < 7.0%, suggesting that military providers appropriately selected well-managed SMs for deployment. HbA1c did not seem to deteriorate during deployment, but they also did not improve despite a reduction in BMI. Concerning trends included the deployment of some SMs with much higher HbA1c, utilization of medications with adverse safety profiles, and the lack of HbA1c and BMI evaluation proximal to deployment departures and returns. However, for SMs meeting adequate glycemic targets, we demonstrated that HbA1c remained stable, supporting the notion that some SMs may safely deploy with diabetes. Improvement in BMI may compensate for factors promoting hyperglycemia in a deployed setting, such as changes in diet and medication availability. Future research should analyze in a prospective fashion, where a more complete array of diabetes and readiness-related measures to comprehensively evaluate the safety of deploying SMs with diabetes.

Extending the pre-processing holding time of whole blood beyond 48 h reduces coagulation FVIII activity and immunoglobulin G content of recovered plasma.

BACKGROUND: Plasma obtained via whole blood (WB) donation may be used either for transfusion or as recovered plasma (RP) for pooling and fractionation. In Canada, transfusable plasma must be processed within 24 h of phlebotomy, while the limit for RP processing is 72 h. We assessed the quality of RP produced by two WB processing methods and as a function of processing time. STUDY DESIGN AND METHODS: RP units produced via the buffy coat method (BCM, n = 26) or whole blood filtration (WBF, n = 52) were tested for: the activities of prothrombin, fibrinogen, von Willebrand Factor (VWF), FV, FVII, and FVIII; the prothrombin time (PT); and total protein and IgG concentration. WBF RP units were evenly divided between those processed <48 h of phlebotomy (shorter-processed) or 48-72 h after phlebotomy (longer-processed). RESULTS: WBF-RP did not differ significantly from BCM-RP in any tested parameter except for FV and FVIII, which exhibited mean reductions of 10.2% and 20%, respectively. Longer-processed WBF-RP did not differ significantly from shorter-processed WBF-RP in any tested parameter except for FVIII activity and IgG concentration, which exhibited mean reductions of 30.1% and 14.3%, respectively. CONCLUSIONS: Canadian RP is currently fractionated into IgG, albumin, fibrinogen, and FVII/VWF concentrates irrespective of its method or time of processing. Our results supported the current approach of fractionating both BCM- and WBF-derived RP, but suggest that greater yields of immunoglobulin and FVIII/VWF products could be obtained if the maximum processing time was reduced from 72 h to 48 h.

Stability of Thawed Apheresis Fresh-Frozen Plasma Stored for up to 120 Hours at 1°C to 6°C.

Regulations concerning the storage of transfusable plasma differ internationally. In Canada, plasma obtained from whole blood donations and frozen within 24 hours of phlebotomy (frozen plasma, FP) may be thawed and transfused within 120 hours of refrigerated storage. However, plasma frozen within 8 hours of phlebotomy following apheresis donation (FFPA) must be transfused within 24 hours of thawing and refrigeration. Our objectives were to measure coagulation factors (F) V, VII, and VIII, fibrinogen activities, and the prothrombin time (PT) in thawed refrigerated FFPA at 0, 24, and 120 hours of storage and to compare these values to those in thawed refrigerated FP. Fibrinogen activity remained unchanged over time, while mean factor levels in 28 FFPA units declined by 17% (FV), 19.7% (FVII), and 54.6% (FVIII) over 120 hours, while PT values rose to 7.6%. Factor activities were significantly higher in FFPA than FP after 120 hours of refrigerated storage. Residual FVIII activities in thawed FFPA met predefined noninferiority criteria compared to thawed FP after 120 hours. These results support a change in Canadian regulations to permit transfusion of thawed FFPA made in a closed system and refrigerated for up to 120 hours, one that could reduce wastage of transfusable plasma.

Factors associated with improved outcomes after second allogeneic hematopoietic cell transplantation for relapsed pediatric leukemia.

A second allogeneic (allo) hematopoietic cell transplant (HCT) is an important therapeutic consideration for patients relapsing after their first. We conducted a retrospective review of 41 pediatric patients with leukemia that underwent a second allo-HCT at our institution. Overall, 53.7 and 43.9 % of patients were alive and disease-free at 1 and 5 years, respectively, after the second allo-HCT. The factors affecting outcome by both univariate and multivariate analysis were interval between transplants and the use of a myeloablative conditioning (MAC) regimen prior to second transplant. Outcomes were inferior in patients who received their second transplant <6 months from their first HCT when compared to patients in whom the interval between HCTs was 6-12 or more than 12 months. Interval between HCTs was also significant when each type of leukemia (acute lymphoblastic leukemia (ALL) n = 21, acute myelogenous leukemia (AML) n = 11, and chronic myelogenous leukemia (CML) n = 7) was analyzed separately. In univariate analysis, use of the same donor and use of a matched sibling donor resulted in significant improved outcome. There was not a significant association between disease-free survival (DFS) and age, remission status, use of total body irradiation (TBI) before second HCT, or type of leukemia. Second allogeneic HCT can be a curative therapeutic option for leukemia patients relapsing after their first transplant. As more targeted therapies have become available, patients that relapse after first HCT are more likely to achieve remission. Therefore, it is anticipated that there will be more candidates for second HCT with improved performance and remission status, ultimately leading to a better outcome with the second HCT.

A quality monitoring program for red blood cell components: in vitro quality indicators before and after implementation of semiautomated processing.

BACKGROUND: Canadian Blood Services has been conducting quality monitoring of red blood cell (RBC) components since 2005, a period spanning the implementation of semiautomated component production. The aim was to compare the quality of RBC components produced before and after this production method change. STUDY DESIGN AND METHODS: Data from 572 RBC units were analyzed, categorized by production method: Method 1, RBC units produced by manual production methods; Method 2, RBC units produced by semiautomated production and the buffy coat method; and Method 3, RBC units produced by semiautomated production and the whole blood filtration method. RBC units were assessed using an extensive panel of in vitro tests, encompassing regulated quality control criteria such as hematocrit (Hct), hemolysis, and hemoglobin (Hb) levels, as well as adenosine triphosphate, 2,3-diphosphoglycerate, extracellular K(+) and Na(+) levels, methemoglobin, p50, RBC indices, and morphology. RESULTS: Throughout the study, all RBC units met mandated Canadian Standards Association guidelines for Hb and Hct, and most (>99%) met hemolysis requirements. However, there were significant differences among RBC units produced using different methods. Hb content was significantly lower in RBC units produced by Method 2 (51.5 ± 5.6 g/unit; p < 0.001). At expiry, hemolysis was lowest in Method 2-produced RBC units (p < 0.05) and extracellular K(+) levels were lowest in units produced by Method 1 (p < 0.001). CONCLUSION: While overall quality was similar before and after the production method change, the observed differences, although small, indicate a lack of equivalency across RBC products manufactured by different methods.

Stability of relevant plasma protein activities in cryosupernatant plasma units during refrigerated storage for up to 5 days postthaw.

BACKGROUND: Cryosupernatant plasma (CSP) is used in Canada for plasma exchange in thrombotic thrombocytopenic purpura. The refrigerated storage time for thawed CSP is limited in many areas to not more than 24 hours postthaw. Because large volumes of CSP are needed for plasma exchange, procedural postponement can lead to product wastage. To determine if CSP storage could be extended, we measured coagulation-related activities in CSP thawed and stored at 1 to 6°C for up to 5 days. STUDY DESIGN AND METHODS: Thirty-six CSP units were thawed, refrigerated, and sampled aseptically at 0, 24, 48, and 120 hours postthaw. Clotting factor activities (Factor [F]V, FVII, FVIII, and fibrinogen) and prothrombin time were measured using an automated coagulation analyzer, and von Willebrand factor (vWF) and ADAMTS13 activities using enzyme-linked immunosorbent assay. RESULTS: Fibrinogen, FVIII, and vWF activities were unchanged from thaw values after 120 hours of storage; ADAMTS13, FV, and FVII activities were significantly lower than at thaw, but mean reductions were only -2.6, -7.7, and -12%, respectively. Losses were proportionately greater in the first 24 hours of refrigerated storage. CONCLUSIONS: Extending the refrigerated storage of CSP from 1 to 5 days had little impact on product quality. The retention of more than 97% of initial mean ADAMTS13 activity after 5 days of refrigerated storage suggests that the shelf life of thawed refrigerated CSP could be extended without meaningful losses of its likely most important ingredients. CSP postthaw storage could be aligned to that of refrigerated thawed frozen plasma, currently available for transfusion in some jurisdictions for up to 5 days postthaw.

Segments from red blood cell units should not be used for quality testing.

BACKGROUND: Nondestructive testing of blood components could permit in-process quality control and reduce discards. Tubing segments, generated during red blood cell (RBC) component production, were tested to determine their suitability as a sample source for quality testing. STUDY DESIGN AND METHODS: Leukoreduced RBC components were produced from whole blood (WB) by two different methods: WB filtration and buffy coat (BC). Components and their corresponding segments were tested on Days 5 and 42 of hypothermic storage (HS) for spun hematocrit (Hct), hemoglobin (Hb) content, percentage hemolysis, hematologic indices, and adenosine triphosphate concentration to determine whether segment quality represents unit quality. RESULTS: Segment samples overestimated hemolysis on Days 5 and 42 of HS in both BC- and WB filtration-produced RBCs (p < 0.001 for all). Hct and Hb levels in the segments were also significantly different from the units at both time points for both production methods (p < 0.001 for all). Indeed, for all variables tested different results were obtained from segment and unit samples, and these differences were not consistent across production methods. CONCLUSION: The quality of samples from tubing segments is not representative of the quality of the corresponding RBC unit. Segments are not suitable surrogates with which to assess RBC quality.

Process improvement by eliminating mixing of whole blood units after an overnight hold prior to component production using the buffy coat method.

The elimination of a thorough manual mixing of whole blood (WB) which takes place following the overnight hold, but before the first centrifugation step, during buffy coat component production at Canadian Blood Services (CBS) was investigated. WB was pooled after donation and split. Pairs of platelet, red blood cell (RBC), and plasma components were produced, with half using the standard method and half using a method in which the mixing step was eliminated. Quality assessments included yield, pH, CD62P expression and morphology for platelets, hemoglobin, hematocrit, hemolysis, and supernatant K(+) for RBCs, and volume and factor VIII activity levels for plasma. All components, produced using either method, met CBS quality control criteria. There were no significant differences in platelet yield between components produced with and without mixing. A significant difference was seen for RBC hemolysis at expiry (P = 0.03), but for both groups, levels met quality control requirements. Noninferiority of components produced without mixing was confirmed for all parameters. Manual mixing is laborious and has a risk of repetitive strain for production staff and its significance is unclear. Elimination of this step will improve process efficiencies without compromising quality.

Quality of frozen transfusable plasma prepared from whole blood donations in Canada: an update.

BACKGROUND: Transfusable plasma is obtained by processing whole blood donations, by apheresis, or as solvent/detergent plasma (SD plasma), a pooled pathogen-reduced plasma product. The quality of plasma is typically assessed by testing the activities of multiple coagulation-related plasma proteins, due to a lack of clinical trial data linking plasma composition to clinical endpoints. We sought to update previous quality surveys of Canadian frozen plasma (FP; manufactured from single donor whole blood donation and frozen within 24h of phlebotomy), to provide transfusionists with a more complete picture of its characteristics. STUDY DESIGN AND METHODS: FP units (n=131) were tested for: the activity of factors V, VII, VIII, X, and XI, protein S (PS), α2-antiplasmin (AP), and fibrinogen; and the activated partial thromboplastin (APTT) and prothrombin (PT) times. Comparisons were made to: previous Canadian FP surveys; and to studies of single-donor plasma and SD plasma from other nations. RESULTS: Mean FVIII, fibrinogen, or APTT values did not differ from the previous annual survey of Canadian FP; FV activity was increased and PT values decreased. FP produced with or without leukoreduction differed only in mean APTT. Canadian FP exhibited generally similar quality to that reported by other organizations in Europe and Asia for similarly manufactured single-donor plasma, but contained notably higher PS and AP (≈ four-fold) activities than did SD plasma. CONCLUSION: Our results indicate that Canadian FP is of similar quality to single-donor products produced in other jurisdictions. While it is of arguably superior in vitro quality to an SD plasma product recently licensed in Canada, these differences are highly unlikely to have clinical significance for most indications for plasma transfusion.

Development of a quality monitoring program for platelet components: a report of the first four years' experience at Canadian Blood Services.

BACKGROUND: A quality monitoring program (QMP) for platelet concentrates (PCs) was implemented at Canadian Blood Services (CBS) to improve standards and to better understand platelet (PLT) products by supplementing routine quality control (QC). STUDY DESIGN AND METHODS: Annual surveys of PCs from CBS production sites were conducted, with four completed to date (QMP Cycles 1-4) spanning two different PC production methods: PLT-rich plasma (PRP) and buffy coat (BC). Randomly selected PCs were sent to a central laboratory and tested 1 day after expiry. An expanded panel of tests including CD62P expression by flow cytometry, mean PLT volume, PLT count and morphology, extent of shape change, and PLT metabolic parameters, were applied. RESULTS: QMP data on the implementation of the BC production method across CBS indicated that BC PCs have less variable in vitro quality measures than PRP PCs. For the QC parameters pH and PLT count per unit, the range of mean values from each site for QMP 3 and 4 fell well within the range defined by regulatory standards, a first step in defining quality benchmarks for PCs. Of the extended panel of quality parameters, CD62P expression was the most sensitive indicator of change and identified an issue with the implementation of the BC PC production method at one site, which was subsequently remedied. CONCLUSION: A QMP was found to be useful to monitor production processes across sites and highlights best practice approaches while deepening understanding of the quality of PLT products at CBS.

Changes in coagulation factor activity and content of di(2-ethylhexyl)phthalate in frozen plasma units during refrigerated storage for up to five days after thawing.

BACKGROUND: Thawed plasma is typically transfused to supply coagulation factors but factor activity declines during refrigerated storage. Refrigerating thawed plasma for longer than 24 hours could reduce plasma wastage and make plasma more readily available for emergency transfusions. We measured coagulation factor activity and di(2-ethylhexyl)phthalate (DEHP) concentration in frozen plasma (FP) thawed and stored at 1 to 6°C for up to 5 days. STUDY DESIGN AND METHODS: FP units prepared using "top-and-bottom" collection sets were thawed, refrigerated, and sampled aseptically at 0, 24, 72, and 120 hours after thawing (n = 54). Clotting factor activities and prothrombin times (PTs) were measured using an automated coagulation factor analyzer. DEHP was measured by high-performance liquid chromatography after hexane extraction (n = 11). Unit sterility was confirmed using an automated microbial detection system. RESULTS: Factor (F)V and FVIII, but not FVII, declined significantly within 24 hours. By Day 5, mean losses were 20, 14, and 41%, in FV, FVII, and FVIII, respectively; fibrinogen activity did not change. PT values were prolonged by 9% on Day 5. Mean DEHP levels increased from 22 ppm at thaw to 66 ppm on Day 5. CONCLUSIONS: The bulk of coagulation factor activity losses during storage occurred in the first 24 hours. Coagulation factor activities remaining in FP after 5 days did not differ from those previously reported in similar products frozen within 24 hours of phlebotomy. While DEHP levels in 5-day-thawed FP are not of concern for adult patients, for infants, DEHP levels can be minimized by using FP refrigerated for no more than 24 hours.

Biofeedback self-regulation training to treat post-concussion headache in a special operations support soldier.

Biofeedback assisted self-regulation training can be an effective treatment for post-concussion headaches. The following is an example of using biofeedback assisted self-regulation training as an intervention to treat posttrauma headaches in a Special Operations Forces (SOF) support soldier. This Soldier was a 23-year-old male who had suffered a concussion while off duty four months earlier and continued to experience headache. Threemodality biofeedback (temperature, surface electromyogram and skin conduction) was used to help the patient learn to self-regulate and control his headaches. This was accomplished over four visits over two weeks. This was a compressed timeline to allow him to deploy with his unit. This form of treatment can be a viable nonmedication based option for addressing post concussion headaches for deploying Soldiers.

Bacterial contamination in platelets: incremental improvements drive down but do not eliminate risk.

BACKGROUND: Bacterial contamination of platelet components (PCs) remains an important cause of transfusion-associated infectious risk. In 2004, Canadian Blood Services (CBS) implemented bacterial testing of PCs using the BacT/ALERT 3D system (bioMérieux). This system has been validated and implemented and continuous monitoring of culture rates allows gathering of data regarding true and false positives as well as false negatives. STUDY DESIGN AND METHODS: National data gathered between March 2004 and October 2010 from 12 CBS sites were analyzed to compare bacterial contamination rates across three platelet (PLT) preparation methods: apheresis, buffy coat, and PLT-rich plasma. Data were compared before and after implementation of protocol changes that may affect bacterial detection or contamination rates. RESULTS: Initial positive rates among the three production methods were significantly different, with apheresis PCs being the highest. The rates of confirmed positives among production methods did not differ significantly (p = 0.668). Increasing sample testing volumes from 4 to 6 mL to 8 to 10 mL significantly increased the rate of initial positives, while confirmed positives increased from 0.64 to 1.63 per 10,000, approaching significance (p = 0.055). Changing the skin disinfection method from a two-step to a one-step protocol did not significantly alter the rate of confirmed positives. During the period of data analysis, eight false-negative cases were reported, with five implicated in adverse transfusion reactions. CONCLUSION: Bacterial testing of PCs and implementation of improved protocols are incrementally effective in reducing the risk of transfusion of bacterially contaminated PLT concentrates; however, the continued occurrence of false-negative results means the risk has not been eliminated.