Viability of AS-3 and SAG-M red cells stored in plastic syringes for pediatric transfusion

BACKGROUND: Pediatric patients may require small-volume transfusions necessitating splitting of red cell (RBC) units. This process usually involves temporary storage of aliquots in pediatric blood bags or, in some cases, plastic syringes, until they are transfused. While many studies have been published on the efficacy of storage in blood bags, there is little evidence to show that RBCs are safe and effective for transfusion after separation into plastic syringe aliquots. STUDY DESIGN AND METHODS: Donor RBC units, stored in either SAG-M (n = 10) or AS-3 additive (n = 11), were split into transfer bags and plastic syringes and stored at either 4 degrees C or room temperature (RT). Half of the aliquots were also irradiated at 25 Gy. RBCs were monitored after 0, 4, and 24 hours of storage with the following variables to assess cellular function and viability: adenosine triphosphate, percent hemolysis, hematocrit, pH, lactate dehydrogenase, extracellular potassium, sodium, and RBC indices. RESULTS: There was no difference found between irradiated and nonirradiated aliquots or aliquots stored in the refrigerator versus those stored at RT. Significant differences between aliquots stored in approved transfer bags and those stored in syringes were not identified. CONCLUSIONS: Irradiation and storage of aliquoted RBCs demonstrated expected but not significant changes in the in vitro variables. Storage for up to 24 hours in syringes does not have a greater detrimental effect on RBCs than storage in transfer bags, making products stored in either container safe for transfusion to pediatric patients.     

Storage of platelets on flatbed agitators in polyvinyl chloride blood bags plasticized with tri(2-ethylhexyl) trimellitate

Data are presented showing that platelets in polyvinyl chloride blood bags plasticized with tri(2-ethylhexyl) trimellitate can be stored on flatbed agitators (shakers) without the pH falling below 6.0. The lowest pH seen after 7 days of storage in 46 units with platelet yields ranging from 3.6 to 13.3 X 10(10) per unit was 6.43. These bags have a O2 transmission rate of 13.3 mumol per hour per bag. Platelet bags with a O2 transmission rate of 7.9 mumol per hour per bag experience a pH fall after 5 days of storage on the shaker in units whose platelet yield on average exceeds 10 X 10(10). Platelets can be stored on first-generation shakers (70 cycles/min, stroke = 1 inch) without an attempt at manual resuspension of the platelet button. The count after 30 minutes on the shaker averaged 89 +/- 15 percent of the expected count, indicating that resuspension was nearly complete after a relatively short period. Red cells, but not platelets, settled out during storage on the shaker.     

Frozen storage of 11 units of sickle cell red cells for autologous transfusion of a single patient

A patient with sickle cell disease and multiple alloantibodies required frozen storage of autologous red cells (RBC) to provide the RBC volume equivalent of 6 units of normal donor blood for an orthopedic surgical procedure. Eleven 600-ml donations were made at 4-week intervals, without significant change in hemoglobin concentration, hematocrit, or reticulocyte count, and with only small decreases in serum iron and ferritin concentrations. Minor modifications of a glycerolization and deglycerolization procedure described recently were used. We report in vitro recoveries of deglycerolized RBC from the 11 units following frozen storage for 27 to 391 days. Despite use of a single donor and adherence to a standardized processing protocol, considerable variation in the percent in vitro RBC recovery was observed (51-81%). In vivo survival of an aliquot following frozen storage for 27 days was identical with fresh autologous RBC (100% at 1 hr, 88% at 24 hr, one-half disappearance of 7.5 days). Autologous transfusion of RBC recovered from 7 units after storage for as long as 126 days was uneventful.     

Core temperature changes in resuspended red blood cells (RBCs) and pediatric RBCs removed from refrigerated storage

BACKGROUND: The 30-minute rule, whereby intact red blood cell (RBC) products may be returned to stock if returned to 4°C storage within 30 minutes of issue, was established many years ago. It was based on observations that the core temperature of units of whole blood removed from storage temperatures of 1 to 6°C, and left at room temperature, would reach 10°C at between 45 minutes and 1 hour.
STUDY DESIGN AND METHODS: Forty-one units of RBCs resuspended leukoreduced and 8 units of pediatric RBCs resuspended leukoreduced were exposed to ambient temperature for periods of time between 0 and 60 minutes. Core temperatures of all units were measured at 1-minute or 5-minute intervals.
RESULTS: Resuspended RBCs units reached a mean core temperature of 10°C at 15 minutes, 12.7°C at 30 minutes, and 15°C at 60 minutes. Pediatric RBCs reached a mean core temperature of 12.8°C at 15 minutes, 15.5°C at 30 minutes, and 17.8°C at 60 minutes.
CONCLUSION: In view of our results, and the range of RBC products now available, it may be timely for blood services to review and reduce the 30-minute rule.     

Survival of red blood cells after transfusion: a comparison between red cells concentrates of different storage periods

BACKGROUND: The use of fresh red blood cells (RBCs) is recommended for critically ill patients and patients undergoing surgery, although there is no conclusive evidence that this is beneficial. In this follow-up study, the short-term and the long-term recovery of irradiated, leukoreduced RBCs transfused after either a short storage (SS) or a long storage (LS) period were compared. By consecutive transfusion of RBCs with a SS and LS period, a direct comparison of their survival within the same patient was possible. STUDY DESIGN AND METHODS: Ten transfusion-requiring patients each received a SS RCCs (stored 0-10 days) and a LS RCCs (stored 25-35 days) consecutively. Short-term and long-term survival of the transfused RBCs was followed by flow cytometry using natural differences in RBC antigens between donors and patients. Posttransfusion recovery (PTR) was measured at several time points after transfusion. RESULTS: The mean 24-hour PTR of SS RBCs is 86.4 +/- 17.8 percent and that of LS RBCs 73.5 +/- 13.7 percent. After the first 24 hours, the mean times to reach a PTR of 50 percent of the 24-hour PTR (T50) and mean potential life spans (mPLs) of the surviving SS and LS RBCs (41 and 116 days and 41 and 114 days, respectively) do not differ. CONCLUSIONS: The mean 24-hour PTR of both SS and LS RBCs complies with the guidelines, even in a compromised patient population. The 24-hour PTR of SS RBCs, however, is significantly higher than that of LS RBCs. The remaining population of SS and LS RBCs has a nearly identical long-term survival. Therefore, depletion of the removal-prone RBCs before transfusion may be an efficient approach for product improvement.     

113名地中海贫血患者输注2629袋红细胞情况分析

目的掌握"地贫之家"患者的用血规律,为开展"地贫之家"的医院提供参考。方法对本院2016年6月开设"地贫之家"起至2019年5月的113名地中海贫血患者的2 629袋红细胞输注情况进行回顾性分析。结果 "地贫之家"患者ABO血型分布与所在的华南地区ABO血型分布大致相当。患者中位数年龄为9岁(6,15),93.8%(106/113)为30周岁以下,尤其以儿童及青少年为主。总体用血量逐渐增加,每年1月至2月和7月至8月的寒暑假回落,主要集中在非工作日输注。结论新建"地贫之家"用血有一定规律,输血科可参考患者的血型分布、用血周期变化制定储血计划,安排人力资源,合理安全使用血液资源。     

Circulatory risk in the transfusion of red blood cells with impaired flow properties induced by storage

Red blood cell (RBC) flow properties (FPs), specifically their deformability, aggregability, and adherence to endothelial cells, play major roles in blood circulation. Their impairment, as occurs under various blood banking conditions, may contribute to circulatory impairment in recipients. Recent studies and meta-analyses show that the transfusion of stored RBCs (stRBCs) may be less beneficial than that of freshly collected units, which may thus adversely affect recipients, especially their circulatory function, thereby pointing to a potential role in the alteration of FPs of stRBCs. In this review, we present an up-to-date summary of the studies on the FP of stRBCs, clearly showing that they may be impaired at an early stage of storage, which may contribute considerably to transfusion-associated circulatory impairment in recipients. The alteration of the FPs of stRBC is attenuated by prestorage leukoreduction and/or poststorage "rejuvenation." However, because these procedures, especially rejuvenation, are costly and are associated with an increased risk of bacterial contamination, there is an urgent need to establish better methods of improving the hemodynamic function of stRBCs before their transfusion. It is therefore proposed that the FPs of stRBC may be important measures of the outcome of RBC transfusions. Monitoring such functions would thereby introduce necessary criteria and new tools for the quality control of stRBC units, making an important contribution to transfusion therapy.     

Expression of CD47 (integrin-associated protein) decreases on red blood cells during storage.

In light of recent studies that demonstrate that CD47 antigen is an important "self-recognition" marker involved in protecting circulating red blood cells (RBCs) from phagocytosis by macrophages, the aim of the present study was to investigate whether CD47 expression on RBCs is altered during storage. Red cell concentrates (RCCs) were prepared and stored at 4 degrees C and samples were collected on days 1, 14, 28 and 42 post donation. RBCs were labelled with anti-CD47 antibody and analysed by flow cytometry. A small but significant and progressive decrease in CD47 antigen expression was observed in non-irradiated and irradiated RBCs stored for 14 days onwards. CD47 was also detected in increasing quantities in supernatant from RCCs after 14 days of storage. It is proposed that loss of CD47 during storage, in addition to other biophysical changes, may target many transfused RBCs for clearance from the transfusion recipient's circulation.     

The societal unit cost of allogenic red blood cells and red blood cell transfusion in Canada

BACKGROUND: There is a dearth of information about the cost of allogenic red blood cells (RBCs) and RBC transfusion in Canada in the aftermath of the Canadian blood system reorganization and the introduction of various safety measures. The unit cost of allogenic RBCs and RBC transfusion in Canada in 1994 was estimated at 152.17 US dollars. The objective of this study was to determine the unit cost of allogenic RBC transfusion in Canada from a societal perspective. STUDY DESIGN AND METHODS: A cost-structure analysis using the cost information from 2001 through 2002 was used. Costs of blood collection, production, distribution, delivery (hospital transfusion service processing and patient administration), transfusion reaction management, and opportunity cost of donor's time were included in the analysis. Canadian Blood Services and Héma-Québec supplied the data for collection, production, and distribution stages. Delivery and transfusion reaction costs were collected from eight hospitals across six Canadian provinces. In-patient costs were assessed for the intensive care unit, emergency, general medicine ward, and operating room. RESULTS: The aggregate mean societal unit cost of RBCs transfused on an inpatient basis in 2002 was 264.81 US dollars (95% confidence interval [CI], 256.29 dollars-275.65 dollars). The mean cost of blood collection, production, and distribution was 202.74 US dollars (95% CI, 199.63 dollars-204.31 dollars), the mean opportunity cost of donor time was 18.21 US dollars (95% CI, 17.11 dollars-21.63 dollars), the mean cost of hospital transfusion service processing was 16.65 US dollars (95% CI, 13.50 dollars-19.79 dollars), of RBC transfusion was 26.92 US dollars (95% CI, 25.33 dollars-28.52 dollars), and of transfusion reaction management was 0.29 US dollars(95% CI, 0.22 dollars-0.36 dollars). There were substantial variations in hospital transfusion service processing and RBC transfusion costs across hospitals. CONCLUSION: The societal unit cost of RBC transfusion has doubled since 1994 to 1995. Further increases in unit costs would be expected as additional safety measures are introduced. This will have important financial implications for treating patient populations that require a high level of RBC transfusions.     

Investigation of red blood cells from alpha1,3-galactosyltransferase-knockout pigs for human blood transfusion

BACKGROUND: Pigs are a potential source of red blood cells (RBCs) for transfusion into humans, but the pre‐sence of galactose‐α1,3‐galactose (Gal) epitopes on their surface, against which humans have anti‐Gal, has been perceived as a major barrier. α1,3‐Galactosyltransferase gene‐knockout pigs, which do not express Gal epitopes on RBCs (Gal–/–), have recently become available. STUDY DESIGN AND METHODS: In vitro, RBCs from Gal–/– pigs were exposed to sera from naïve humans or baboons or from baboons previously sensitized to pig antigens; immunoglobulin binding was measured by flow cytometry, and cytotoxicity, by a hemolytic assay. In vivo, relatively small numbers of Gal–/– RBCs were transfused into two nonsensitized untreated baboons. The survival of pig RBCs was detected by flow cytometry. RESULTS: In vitro, binding of immunoglobulin (Ig) M from naïve human or baboon sera was detected to Gal–/– RBCs but was significantly less than to Gal+/+ RBCs; IgG binding to Gal–/– RBCs was absent or minimal. Sera had minimal cytotoxicity to Gal–/– RBCs compared to Gal+/+ RBCs. Sensitized baboon sera demonstrated much higher IgG binding to Gal–/– RBCs and increased cytotoxicity, but again these were less than to Gal+/+ RBCs. In vivo, the transfusion of relatively small volumes of Gal–/– RBCs was followed by detection of the cells in the baboon's blood for only 5 minutes. CONCLUSION: Pig RBCs are rapidly phagocytosed from the primate circulation by a mechanism not involving anti‐Gal.     

不同保存期全血制备洗涤红细胞的超微结构变化

目的 探讨不同保存期的全血制备洗涤红细胞前后电镜下红细胞形态的变化。方法 采集CPD—A抗凝全血。实验分Ⅰ～Ⅵ组，分别于4℃保存7、10、15、20、25、30d。于制备前取全血1滴，5％戊二醛固定，经2000r／min离心10min后，分出血浆，取样检测血红蛋白。余下的红细胞再加等量生理盐水，1500r／min离心5min，连续2次，取样为制备后测定组。结果 组Ⅰ和组Ⅱ制备前后红细胞成双面凹的圆盘结构，细胞均匀混悬。组Ⅲ制备前红细胞形态正常，制备后少数红细胞出现聚集状、球形或边缘不整齐，并有棘形红细胞出现。组Ⅳ、组Ⅴ、组Ⅵ于制备前血浆微红；制备后，球形红细胞、棘形红细胞、中问漏孔的红细胞增加。结论 制备洗涤红细胞的最佳时间应在4℃保存10d内的全血，保存15d以后的全血制备洗涤红细胞形态发生异常变化，出现棘形红细胞，囊泡化后的红细胞易溶血，红细胞寿命缩短，影响洗涤红细胞的质量。     

Beneficial effect of transfusion with low-affinity red blood cells in endotoxemia

BACKGROUND: Sepsis caused by endotoxins such as lipopolysaccharide (LPS) impairs the microcirculation, diminishing tissue blood supply and aggravates systemic hypoxia. A novel lower-affinity hemoglobin (Hb) variant, Hb Presbyterian, enhances oxygen release to peripheral tissues and may improve tissue oxygen supply during sepsis. STUDY DESIGN AND METHODS: This study investigated the effectiveness of Presbyterian Hb in transfusion therapy with LPS-challenged sepsis mouse model. Septic wild-type mice were transfused with RBCs from Presbyterian Hb-carrying mutant mice and wild-type mice. Their survival rates were assessed, and apoptosis of hepatocytes was evaluated. Survival rates of septic Presbyterian mutant mice and the wild-type littermates were also studied. RESULTS: The Presbyterian mutant RBC-transfused septic group survived longer than the wild-type RBC-transfused group. Apoptosis was reduced in the hepatocytes of the former group. Presbyterian mutant mice themselves, however, did not have stronger resistance to LPS-induced sepsis. CONCLUSION: Transfusion of low-affinity Hb-containing RBCs has beneficial effects in septic mice.