Monitoring of RBC rheology after cryopreservation to detect autologous blood doping in vivo? A pilot study

BACKGROUND: Autologous blood doping (ABD) is applied to improve performance capacity. ABD includes blood donation, red blood cell (RBC) storage at –80°C and re-infusion prior to or during competition. ABD is not directly detectable with current detection techniques. OBJECTIVE: Since cryopreservation is known to affect RBC physiology in vitro, the aim of the study was to examine whether these alterations are detectable in vivo. METHODS: Blood from six healthy male donors was transferred into conventional blood bags, cryopreserved, stored for 18 weeks at –80°C and re-infused with a RBC volume corresponding to ∼4% of total blood volume into respective donor. RBC physiology parameters were measured before blood donation/re-infusion, and 0/1/2/6/24/48/72 h and 1 w post re-infusion. RESULTS: RBC parameters and age markers were unaffected during intervention. RBC deformability increased from pre-blood-sampling to pre-re-infusion while deformability and viscosity values remained unaltered post re-infusion. RBC nitric oxide associated analytes, metabolic parameters and electrolyte concentrations remained unaffected. CONCLUSIONS: The data of this pilot study indicate that the increase in RBC deformability might be related to neoformation of RBC after blood donation. The lack of changes in tested parameters might be related to the low re-infused RBC volume which might explain differences to in vitro results.

The effect of red blood cell transfusion on plasma hepcidin and growth differentiation factor 15 in gastric cancer patients: a prospective study

Background

Hepcidin and growth differentiation factor 15 (GDF-15) have been reported to be highly expressed in various cancers. Serum hepcidin and GDF-15 levels were demonstrated to be potential prognostic markers in cancers. This study aims to evaluate the effect of red blood cell (RBC) transfusion on plasma hepcidin and GDF-15 in gastric cancer patients.

Methods

In this prospective study, 40 patients with gastric cancer were eligible for this study. Peripheral blood samples were obtained before and within 24 h after RBC transfusion. A routine blood test was performed before transfusion and within 24 h post-transfusion. Plasma hepcidin, GDF-15, interleukin 6 (IL-6) and erythropoietin were determined by ELISA.

Results

In patients with metastasis, plasma hepcidin (P=0.02), and GDF-15 (P=0.01) levels were higher than without metastasis. Plasma hepcidin was increased after RBC transfusion (P=0.001), while plasma erythropoietin was decreased after transfusion (P=0.03). However, RBC transfusion did not affect plasma GDF-15 (P=0.32) and IL-6 (P=0.12). The effect of RBC transfusion on variables did not differ between metastatic and non-metastatic patients. The mean percentage change of hepcidin in transfusion volume 4 unit (U) was more than 2 U.

Conclusions

RBC transfusion could increase plasma hepcidin and have no effect on plasma GDF-15 in gastric patients.

Exploring the microvascular impact of red blood cell transfusion in intensive care unit patients

BACKGROUND

Red blood cell (RBC) transfusion is a common treatment for hospitalized patients. However, the effects of RBC transfusion on microvascular function remain controversial.

METHODS

In a medical ICU in a tertiary teaching hospital, we prospectively included anemic patients requiring RBC transfusion. Skin microvascular reactivity was measured before and 30 min after RBC transfusion. Plasma was collected to analyze intravascular hemolysis and draw the lipidomic and cytokine profiles.

RESULTS

In a cohort of 59 patients, the median age was 66 [55-81] years and SAPS II was 38 [24-48]. After RBC transfusion, endothelium-dependent microvascular reactivity improved in 35 (59%) patients, but worsened in 24 others (41%). Comparing clinical and biological markers revealed that baseline blood leucokyte counts distinguished improving from worsening patients (10.3 [5.7; 19.7] vs. 4.6 [2.1; 7.3] × 109/L; p = 0.001) and correlated with variations of microvascular reactivity (r = 0.36, p = 0.005). Blood platelet count was also higher in improving patients (200 [97; 280] vs 160 [40; 199] × 103/mL, p = 0.03) but did not correlate with variations of microvascular reactivity. We observed no intravascular hemolysis (HbCO, heme, bilirubin, LDH), but recorded a significant increase in RBC microparticle levels specific to improving patients after transfusion (292 [108; 531] vs. 53 [34; 99] MP/μL; p = 0.03). The improvement in microvascular dilation was positively correlated with RBC microparticle levels (R = 0.83, p < 0.001) and conversion of arachidonic acid into vasodilating eicosanoids.

CONCLUSIONS

Patients displaying an improved microvascular reactivity after RBC transfusion had high blood leukocyte counts, increased RBC microparticle formation, and enhanced metabolism of arachidonic acid into vasodilating lipids. Our data suggested a contribution of recipient leukocytes to the vascular impact of RBC transfusion.

Cell-Free Plasma Hemoglobin and Male Gender Are Risk Factors for Acute Kidney Injury in Low Risk Children Undergoing Cardiopulmonary Bypass

OBJECTIVES

To determine the relationship between the production of cell-free plasma hemoglobin and acute kidney injury in infants and children undergoing cardiopulmonary bypass for cardiac surgery.

DESIGN

Prospective observational study.

SETTING

Twelve-bed cardiac ICU in a university-affiliated children's hospital.

PATIENTS

Children were prospectively enrolled during their preoperative outpatient appointment with the following criteria: greater than 1 month to less than 18 years old, procedures requiring cardiopulmonary bypass, no preexisting renal dysfunction.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Plasma and urine were collected at baseline (in a subset), the beginning and end of cardiopulmonary bypass, and 2 hours and 24 hours after cardiopulmonary bypass in 60 subjects. Levels of plasma hemoglobin increased during cardiopulmonary bypass and were associated (p < 0.01) with cardiopulmonary bypass duration (R = 0.22), depletion of haptoglobin at end and 24 hours after cardiopulmonary bypass (R = 0.12 and 0.15, respectively), lactate dehydrogenase levels at end cardiopulmonary bypass (R = 0.27), and change in creatinine (R = 0.12). Forty-three percent of patients developed acute kidney injury. There was an association between plasma hemoglobin level and change in creatinine that varied by age (overall [R = 0.12; p < 0.01]; in age > 2 yr [R = 0.22; p < 0.01]; and in < 2 yr [R = 0.03; p = 0.42]). Change in plasma hemoglobin and male gender were found to be risk factors for acute kidney injury (odds ratio, 1.02 and 3.78, respectively; p < 0.05).

CONCLUSIONS

Generation of plasma hemoglobin during cardiopulmonary bypass and male gender are associated with subsequent renal dysfunction in low-risk pediatric patients, especially in those older than 2 years. Further studies are needed to determine whether specific subgroups of pediatric patients undergoing cardiopulmonary bypass would benefit from potential treatments for hemolysis and plasma hemoglobin-associated renal dysfunction.

Cryopreserved packed red blood cells in surgical patients: past, present, and future

Since the advent of anticoagulation and component storage of human blood products, allogeneic red blood cell transfusion has been one of the most common practices in modern medicine. Efforts to reduce the biochemical effects of storage, collectively known as the red blood cell storage lesion, and prolong the storage duration have led to numerous advancements in erythrocyte storage solutions. Cryopreservation and frozen storage of red blood cells in glycerol have been successfully utilised by many civilian and military institutions worldwide. Through progressive improvements in liquid storage of erythrocytes in novel storage solutions, the logistical need for cryopreserved red blood cells in the civilian setting has diminished. A growing body of current literature is focused on the clinical consequences of packed red blood cell age. Modern cryopreservation techniques show promise as a cost-effective method to ameliorate the negative effect of the red blood cell storage lesion, while meeting the technical and logistical needs of both civilian and military medicine. This review outlines the history of red blood cell cryopreservation, the clinical impact of red cell storage, and highlights the current literature on frozen blood and its impact on modern transfusion.

The outsider adverse event in transfusion: Inflammation

In order to maintain adequate inventories of red blood cells (RBCs) for transfusion, RBC units are refrigerator-stored for variable amounts of time prior to transfusion. A subset of RBCs is damaged during prolonged storage. Clearance of these damaged RBCs is hypothesized to induce an inflammatory response in the transfusion recipient. However, there is controversy over whether RBC transfusions are in fact associated with inflammation, and more generally, whether current standards for maximal RBC storage times are safe. We will explore the evidence for and against this outsider adverse event in transfusion: whether certain RBC transfusions do or do not cause inflammation.

Red blood cell components: Meeting the quantitative and qualitative transfusion needs

Red blood cell (RBC) transfusion is a very common therapeutic intervention. However, because of multiple recent studies improving our understanding of appropriate transfusion scenarios, the total number of RBC units transfused per year is actually decreasing in the developed world and there are no longer major shortages of RBC products for general use. Nonetheless, there are an increasing number of "special" uses, which can put strains on the blood supply for particular types of products; these may produce shortages of specific types of RBCs or require collections targeting certain types of donors. This review will focus on several broad topics, including providing some examples of "special" settings that require, or could require, special types of RBC products.

A retrospective analysis of the effect of blood transfusion on cerebral oximetry entropy and acute kidney injury

Purpose:

Acute anemia is associated with both cerebral dysfunction and acute kidney injury and is often treated with red blood cell transfusion. We sought to determine if blood transfusion changed the cerebral oximetry entropy, a measure of the complexity or irregularity of the oximetry values, and if this change was associated with subsequent acute kidney injury.

Methods:

This was a retrospective, case-control study of patients undergoing cardiac surgery with cardiopulmonary bypass at a tertiary care hospital, comparing those who received a red blood cell transfusion to those who did not. Acute kidney injury was defined as a perioperative increase in serum creatinine by ⩾26.4 μmol/L or by ⩾50% increase. Entropy was measured using approximate entropy, sample entropy, forbidden word entropy and basescale4 entropy in 500-point sets.

Results:

Forty-four transfused patients were matched to 88 randomly selected non-transfused patients. All measures of entropy had small changes in the transfused group, but increased in the non-transfused group (p<0.05, for all comparisons). Thirty-five of 132 patients (27%) suffered acute kidney injury. Based on preoperative factors, patients who suffered kidney injury were similar to those who did not, including baseline cerebral oximetry levels. After analysis with hierarchical logistic regression, the change in basescale4 entropy (odds ratio = 1.609, 95% confidence interval = 1.057–2.450, p = 0.027) and the interaction between basescale entropy and transfusion were significantly associated with subsequent development of acute kidney injury.

Conclusions:

The transfusion of red blood cells was associated with a smaller rise in entropy values compared to non-transfused patients, suggesting a change in the regulation of cerebral oxygenation, and these changes in cerebral oxygenation are also associated with acute kidney injury.

Autologous Doping with Cryopreserved Red Blood Cells - Effects on Physical Performance and Detection by Multivariate Statistics

The discovery of erythropoietin (EPO) simplified blood doping in sports, but improved detection methods, for EPO has forced cheating athletes to return to blood transfusion. Autologous blood transfusion with cryopreserved red blood cells (RBCs) is the method of choice, because no valid method exists to accurately detect such event. In endurance sports, it can be estimated that elite athletes improve performance by up to 3% with blood doping, regardless of method. Valid detection methods for autologous blood doping is important to maintain credibility of athletic performances. Recreational male (N = 27) and female (N = 11) athletes served as Transfusion (N = 28) and Control (N = 10) subjects in two different transfusion settings. Hematological variables and physical performance were measured before donation of 450 or 900 mL whole blood, and until four weeks after re-infusion of the cryopreserved RBC fraction. Blood was analyzed for transferrin, iron, Hb, EVF, MCV, MCHC, reticulocytes, leucocytes and EPO. Repeated measures multivariate analysis of variance (MANOVA) and pattern recognition using Principal Component Analysis (PCA) and Orthogonal Projections of Latent Structures (OPLS) discriminant analysis (DA) investigated differences between Control and Transfusion groups over time. Significant increase in performance (15 ± 8%) and VO2max (17 ± 10%) (mean ± SD) could be measured 48 h after RBC re-infusion, and remained increased for up to four weeks in some subjects. In total, 533 blood samples were included in the study (Clean = 220, Transfused = 313). In response to blood transfusion, the largest change in hematological variables occurred 48 h after blood donation, when Control and Transfused groups could be separated with OPLS-DA (R2 = 0.76/Q2 = 0.59). RBC re-infusion resulted in the best model (R2 = 0.40/Q2 = 0.10) at the first sampling point (48 h), predicting one false positive and one false negative. Over all, a 25% and 86% false positives ratio was achieved in two separate trials. In conclusions, autologous re-infusion of RBCs increased VO2max and performance as hypothesized, but hematological profiling by multivariate statistics could not reach the WADA stipulated false positive ratio of <0.001% at any time point investigated. A majority of samples remained within limits of normal individual variation at all times.

Red blood cell transfusion-induced inflammation: myth or reality

Red blood cells (RBCs) destined for transfusion can be refrigerator stored for up to 42 days prior to transfusion. Our studies in mice and dogs suggest that transfusion of older, stored RBCs, but not fresh RBCs, produce acute elevations in circulating pro-inflammatory cytokine levels. Although our study in healthy adult human volunteers failed to demonstrate a pro-inflammatory cytokine response following transfusion of RBCs stored for 40-42 days, a recent study in preterm infants suggests that RBC transfusions are associated with a pro-inflammatory response. Thus, whether RBC transfusions, particularly of older, stored RBCs, result in a pro-inflammatory cytokine response, is still an unresolved issue. Animal studies suggest this to be true, yet human studies have yet to demonstrate definitively that such an inflammatory response occurs. Potential explanations for this include differences between human and animal biology, the dose of RBCs transfused, and baseline differences in levels of inflammation. This review will summarize the currently available evidence and approaches to resolving whether transfusions of older, stored RBCs are associated with inflammation in recipients.

Utilization and quality of cryopreserved red blood cells in transfusion medicine

Cryopreserved (frozen) red blood cells have been used in transfusion medicine since the Vietnam war. The main method to freeze the red blood cells is by usage of glycerol. Although the usage of cryopreserved red blood cells was promising due to the prolonged storage time and the limited cellular deterioration at subzero temperatures, its usage have been hampered due to the more complex and labour intensive procedure and the limited shelf life of thawed products. Since the FDA approval of a closed (de) glycerolization procedure in 2002, allowing a prolonged postthaw storage of red blood cells up to 21 days at 2-6°C, cryopreserved red blood cells have become a more utilized blood product. Currently, cryopreserved red blood cells are mainly used in military operations and to stock red blood cells with rare phenotypes. Yet, cryopreserved red blood cells could also be useful to replenish temporary blood shortages, to prolong storage time before autologous transfusion and for IgA-deficient patients. This review describes the main methods to cryopreserve red blood cells, explores the quality of this blood product and highlights clinical settings in which cryopreserved red blood cells are or could be utilized.

Red blood cell transfusions for thalassemia: results of a survey assessing current practice and proposal of evidence-based guidelines

BACKGROUND

In the absence of curative treatment, such as stem cell transplant, regular transfusions remain the mainstay of therapy for individuals with thalassemia major, a syndrome that results from marked ineffective erythropoiesis and the resultant anemia. The primary objectives of transfusion therapy are twofold: to suppress ineffective erythropoiesis and to ensure appropriate growth and development through childhood. In practice, a number of different transfusion protocols are in use across the developed world, with on-demand transfusion still being the paradigm in most of the developing world with limited resources.

STUDY DESIGN AND METHODS

To investigate perceived differences in transfusion practice, a self-reported electronic survey was disseminated to eight US thalassemia treatment centers in February 2011. The survey was divided into sections ranging from laboratory and clinical practices to emerging transfusion-transmitted diseases.

RESULTS

The survey response rate was 100%. The total number of transfused patients was 411. One-hundred percent of institutions used leukoreduced blood. No centers routinely provided cytomegalovirus-seronegative red blood cells (RBCs). Half the centers provided irradiated RBCs; only one routinely provided washed RBCs, and none transfused RBCs of defined storage age. Seventy-five percent of centers routinely phenotyped thalassemia patients' RBC antigens; 50% prophylactically matched for Rh and K antigens. The frequency of antibody investigations varied widely, and 25% of centers routinely medicated patients before transfusion.

CONCLUSION

Eight thalassemia centers in the United States were surveyed to determine the uniformity of transfusion practice. The variability of the results was surprising. Consequently, we performed a literature review and propose an evidence-based protocol for routine transfusion therapy for patients with thalassemia.

Chimerism in transfusion medicine: the grandmother effect revisited

Transfusion therapy is complicated by the production of alloantibodies to antigens present in the donor and lacking in the recipient through the poorly-understood but likely multi-factorial process of alloimmunization. The low prevalence of alloimmunization in transfused patients (6.1%) (1) suggests that processes central to immunologic tolerance may be operating in the vast majority of transfused patients who do not produce alloantibodies. Using RhD as a prototype, evidence is reviewed that the ability to make antibodies to red blood cell (RBC) antigens may result in part from immunologic tolerance acquired in utero. These ideas are extended to other examples of maternal microchimerism (MMc) of other non-inherited maternal antigens (NIMA). An evolutionary argument is offered that multi-generational immunity supports the hypothesis that MMc may partly explain the "non-responder" phenotype in RBC alloimmunization.

Updated role of nitric oxide in disorders of erythrocyte function

Nitric oxide is a potent vasodilator that plays a critical role in disorders of erythrocyte function. Sickle cell disease, paroxysmal nocturnal hemoglobinuria and banked blood preservation are three conditions where nitric oxide is intimately related to dysfunctional erythrocytes. These conditions are accompanied by hemolysis, thrombosis and vasoocclusion. Our understanding of the interaction between nitric oxide, hemoglobin, and the vasculature is constantly evolving, and by defining this role we can better direct trials aimed at improving the treatments of disorders of erythrocyte function. Here we briefly discuss nitric oxide's interaction with hemoglobin through the hypothesis regarding Snitrosohemoglobin, deoxyhemoglobin, and myoglobin as nitrite reductases. We then review the current understanding of the role of nitric oxide in sickle cell disease, paroxysmal nocturnal hemoglobinuria, and banked blood, and discuss therapeutics in development to target nitric oxide in the treatment of some of these disorders.

Transfusion of 28-day-old leucoreduced or non-leucoreduced stored red blood cells induces an inflammatory response in healthy dogs

BACKGROUND AND OBJECTIVES

Studies in mice suggest that rapid transfusions of red blood cells (RBCs), refrigerator stored for longer durations, induce a pro-inflammatory cytokine response. Studies in human neonates confirm these findings; however, to date, adult human studies have failed to replicate these findings. We used healthy research dogs to begin to examine the factors affecting the cytokine response to transfusion.

MATERIALS AND METHODS

In a prospective study, healthy dogs were randomized for two autologous packed RBC transfusions after 7 (i.e. 'fresh') and 28 (i.e. 'old') days of storage, or after 28 and 7 days of storage, with or without prestorage leucoreduction (LR).

RESULTS

No significant differences were observed between LR and non-LR transfusions for all circulating analytes measured following transfusion. A pro-inflammatory cytokine response, exemplified by monocyte chemoattractant protein-1, was observed 6 h after only old RBC transfusions, irrespective of infusion rate (P < 0·001). This response was accompanied by increased neutrophil counts (P < 0·001) and decreased platelet counts (P < 0·001).

CONCLUSION

In healthy dogs, old RBC transfusions induce inflammation, which is unaffected by infusion rate.