Karafin Matthew S, Kelly Shannon, Chapman Kathleen M, Kreuziger Lisa Baumann, Manis John P, Dinardo Carla, Josephson Cassandra D, Stone Mars, Roubinian Nareg H, Branchford Brian, Sachais Bruce S, Hailu Benyam, Sabino Ester C, Hod Eldad A, Custer Brian
Department of Pathology and Laboratory Medicine, University of North Carolina School of Medicine, Chapel Hill, NC, USA.
Department of Pediatrics, University of California, San Francisco Benioff Children's Hospital Oakland, Oakland, CA, USA.
Blood Transfus. 2025 Sep-Oct;23(5):418-432. doi: 10.2450/BloodTransfus.1026. Epub 2025 May 9.
Variability in blood donors, components, and recipients are known to affect transfusion outcomes, yet the combined effects of these factors remains unclear.
The Red Blood Cell - Improving Transfusions for Chronically Transfused Recipients (RBC-IMPACT) study was a multi-center longitudinal study conducted in the United States (US) and Brazil over two years to investigate RBC survival after transfusion (Aim 1) and acute increase in iron post transfusion (Aim 2) (see https://clinicaltrials.gov/study/NCT05255445). The US RBC-IMPACT study included patients with thalassemia and sickle cell disease (SCD) and, in Aim 2 only, children with hematology-oncology diseases with a hypoproliferative bone marrow. In Brazil, the study was conducted within an established SCD cohort. Blood samples were collected immediately before and after RBC transfusion to measure hemoglobin (Hb), hemoglobin A (HbA) in SCD, and markers of iron and hemolysis. Samples were collected two hours post transfusion in a subset of participants receiving primarily single unit transfusions for Aim 2. Transfusate samples were collected from transfused units. Single nucleotide polymorphism array typing of donors and recipients to measure genetic variants including those associated with increased in vitro hemolysis of stored RBCs was conducted. Comprehensive information regarding donors, components and some recipient data were linked to key clinical data extracted from recipients' medical records to assess factors associated with RBC transfusion effectiveness.
The outcomes for Aim 1 were RBC survival between successive transfusions, calculated as ΔHbA per day for SCD and by ΔHb per day for thalassemia, and Δbilirubin for both patient groups. The primary outcome for Aim 2 was change in serum iron from before to 2 hours after transfusion.
This study will be the most detailed and granular evaluation of the predictive variables that may optimize RBC effectiveness and safety in these chronically transfused patient populations.
已知献血者、血液成分和受血者的变异性会影响输血结果，但这些因素的综合影响仍不清楚。
红细胞——改善长期输血受血者的输血（RBC-IMPACT）研究是一项在美国和巴西进行的为期两年的多中心纵向研究，旨在调查输血后红细胞的存活情况（目标1）以及输血后铁的急性增加情况（目标2）（见https://clinicaltrials.gov/study/NCT05255445）。美国的RBC-IMPACT研究纳入了地中海贫血和镰状细胞病（SCD）患者，仅在目标2中纳入了骨髓增生低下的血液肿瘤疾病患儿。在巴西，该研究是在一个已有的SCD队列中进行的。在红细胞输血前后立即采集血样，以测量血红蛋白（Hb）、SCD中的血红蛋白A（HbA）以及铁和溶血标志物。在目标2中，对主要接受单单位输血的一部分参与者，在输血后两小时采集样本。从输注的单位采集输注物样本。对献血者和受血者进行单核苷酸多态性阵列分型，以测量包括与储存红细胞体外溶血增加相关的遗传变异。将有关献血者、成分和一些受血者数据的综合信息与从受血者病历中提取的关键临床数据相联系，以评估与红细胞输血有效性相关的因素。
目标1的结果是连续两次输血之间的红细胞存活情况，SCD患者按每天的ΔHbA计算，地中海贫血患者按每天的ΔHb计算，两组患者均计算Δ胆红素。目标2的主要结果是输血前至输血后2小时血清铁的变化。
本研究将是对可能优化这些长期输血患者群体中红细胞有效性和安全性的预测变量进行的最详细、最具体的评估。
