Dunbar, Nancy M

Abstract Background Cryoprecipitated antihemophiliac factor (cryo) is primarily used to replenish fibrinogen in acquired coagulopathy. Little has been reported about its usage patterns within hospitals with respect to patient population, frequency of use, and dosing. Study design and methods Cryo production and usage data were collected over 5 years from July 1, 2016, to June 30, 2021, from nationally based blood collection centers in the United States (U.S. n = 2) and Canada ( n = 2) and from eight large academic hospitals, respectively. Usage data for a similar product, purified fibrinogen concentrate were also collected from four hospitals. Results Two U.S. blood collectors reported increases in cryo production normalized to total whole blood collections from 17.4% in 2016 to 22.3% in 2021 and from 16.4% in 2016 to 20.2% in 2021. In contrast, in Canada cryo manufacturing increased slightly in one region (11.3%–12.9%) and decreased (8.0%–2.0%) in the other. Cryo utilization, defined as numbers of patients treated normalized to the inpatient census, and dose administered per patient did not consistently increase and differed significantly between hospitals participating in the study ( p < .0001). Likewise, the departments that most frequently transfused cryo varied between hospitals. Similarly, variations in practice were observed for fibrinogen concentrate usage. Conclusion While much of Canada and Europe have moved towards using fibrinogen concentrate, two large U.S. collectors have increased cryo distribution. The lack of standardization and variability in the clinical practice regarding the use of cryo and fibrinogen concentrate reported by study sites may be attributable to practitioner preference, availability, and/or cost rather than adherence to published evidence or guidelines.

Abstract Background Rho(D) immune globulin (RhIg) is used to reduce RhD alloimmunization in pregnancy. This study describes potential causes for RhD alloimmunization after the development and implementation of RhIg. Study Design and Methods This retrospective descriptive study investigated RhD‐negative patients born in 1965–2005 with anti‐D newly identified during 2018–2022. Transfusion, pregnancy, intravenous drug abuse, and transplantation were considered potential alloimmunization sources. Results There were 1200 study patients (852 females; 348 males) at 30 institutions in 5 countries (USA, Canada, UK, New Zealand, Brazil). Most patients had a single potential source of alloimmunization identified (857/1200, 71%), most commonly pregnancy among females (537/852, 63%) and transfusion among males (180/348, 52%). When multiple potential sources were included, males were more likely than females to have a history of transfusion (235/348 [68%] vs. 149/852 [17%], p < .0001) and confirmed or suspected intravenous drug abuse (100/348 [29%] vs. 138/852 [16%], p < .0001). Among females with a history of pregnancy, 119/718 (17%) had healthcare access issues, 120/718 (17%) had pregnancy in a country where they may not have received RhIg, and 21/718 (3%) refused RhIg. Among patients with a history of transfusion, males were more likely than females to have received RhD‐positive red blood cells or whole blood (143/235 [61%] vs. 30/149 [20%], p < .0001) and/or platelets (84/235 [36%] vs. 19/149 [13%], p < .0001). Discussion Pregnancy was the most frequently identified potential source of RhD alloimmunization among females. Transfusion was most frequent in males. Intravenous drug abuse as a common potential source among patients with RhD alloimmunization merits further study.

AbstractSince 1986, the American Society for Apheresis (ASFA) has published practice guidelines on the use of therapeutic apheresis in the Journal of Clinical Apheresis (JCA) Special Issue. Since 2007, updated guidelines have been published every 3 years to reflect current evidence based apheresis practice with the most recent edition (8th) published in 2019. With each edition, the guidelines are reviewed and updated based on any newly published literature since the last review. The PEXIVAS study, an international, randomized controlled trial comparing therapeutic plasma exchange (TPE) vs no TPE and standard vs reduced dose steroid regimen on the primary composite outcome of end stage renal disease or death in patients with ANCA‐associated vasculitis (AAV), was published in February 2020. This study represents the largest study on the role of therapeutic apheresis in AAV published to date and prompted the JCA Special Issue Writing Committee to reassess the current AAV fact sheet for updates based on this newly available evidence. This interim fact sheet summarizes current ASFA recommendations for the evidence‐based use of therapeutic apheresis in AAV and supersedes the recommendations published in the 2019 guidelines.

BACKGROUNDABO‐incompatible platelet transfusions are common, and transfusions with ABO‐incompatible plasma are increasing with the use of group A plasma and group O whole blood (WB) in emergencies. Many centers screen blood products for anti‐A and/or anti‐B titers to help prevent hemolysis from ABO‐incompatible transfusions, yet titer methods and definition of high titers are not standardized.STUDY DESIGN AND METHODSThis international multicenter study collected data on anti‐A and anti‐B titer practices for plasma, apheresis platelet (AP), and WB units from January 2015 through December 2017 to determine the prevalence of high‐titer units using local definitions.RESULTSA total of 87,701 plasma, AP and WB units were screened for high‐titer anti‐A and/or anti‐B. High‐titer detection rates for group A plasma ranged 0%–13.6%; group A AP 2.7%–9.3%; group O AP 2.3%–65.7%; and group O WB 6.4%–20.7%. At the one center that collected group B AP, the high‐titer rate was 10.9%. High‐titer rates varied from month to month, as well as between years for a given month. There was no clear pattern of when high‐titer units were donated.CONCLUSIONThe prevalence of high‐titer plasma, AP, and WB units varies by titer method and local definition of high titer. Even at the lowest titer threshold of 50, a significant proportion of units had a high‐titer antibody, although the clinical relevance of this finding needs further investigation.

AbstractBackgroundAlthough many apheresis centers offer extracorporeal photopheresis (ECP), little is known about current treatment practices.MethodsAn electronic survey was distributed to assess ECP practice internationally.ResultsOf 251 responses, 137 met criteria for analysis. Most respondents were from North America (80%). Nurses perform ECP at most centers (84%) and the majority of centers treat adults only (52%). Most centers treat fewer than 50 patients/year (83%) and perform fewer than 300 procedures/year (70%). Closed system devices (XTS and/or Cellex) are used to perform ECP at most centers (96%). The most common indications for ECP are acute/chronic skin graft versus host disease (89%) and cutaneous T‐cell lymphoma (63%). The typical wait time for ECP treatment is less than 2 weeks (91%). Most centers do not routinely perform quality control assessment of the collected product (66%). There are device‐specific differences in treatment parameters. For example, XTS users more frequently have a minimum weight limit (P = 0.003) and use laboratory parameters to determine eligibility for treatment (P = 0.03). Regardless of device used, the majority of centers assess the clinical status of the patient before each procedure. Greater than 50% of respondents would defer treatment for hemodynamic instability due to active sepsis or heart failure, positive blood culture in the past 24 h or current fever.ConclusionThis survey based study describes current ECP practices. Further research to provide evidence for optimal standardization of patient qualifications, procedure parameters and product quality assessment is recommended.

Background The platelet (PLT) P an G enera D etection test ( PGD ) is a rapid bacterial detection system used to screen PLTs for bacterial contamination. We report a single center 46‐month experience with secondary screening of apheresis PLTs by PGD testing. Study Design and Methods Existing testing records of apheresis PLTs screened by PGD from J uly 2008 to A pril 2012 were reviewed. All PLT units were initially screened by routine postcollection culture methods. Secondary screening using PGD was performed for indated PLTs on PLT storage D ay 4 and for outdated PLTs on D ay 8. Results A total of 8535 apheresis PLTs were available in inventory during the study period. Of these, 5030 (58.9%) were dispensed and transfused before PGD testing and 3505 (41.1%) underwent PGD testing on D ay 4. Twenty‐five units tested on D ay 4 were PGD initial reactive (0.71%). All were confirmed to be false positive by repeat PGD testing in triplicate (n = 20) or by confirmatory culture (n = 5). An additional 364 units that were PGD nonreactive on D ay 4 were approved for transfusion on D ay 6 or D ay 7 due to urgent clinical need. A total of 371 outdated units underwent repeat PGD testing before discard on D ay 8; all were nonreactive. Conclusion Secondary PGD testing of culture‐screened apheresis PLTs results in low yield in a medium‐sized transfusion service. Use of PGD testing on D ay 4 may allow for extension of the apheresis PLT shelf life to D ay 7 for hospitals that face supply constraints.