Cryopreserved red blood cells are superior to standard liquid red blood cells

Autologous Blood Doping Induced Changes in Red Blood Cell Rheologic Parameters, RBC Age Distribution, and Performance

Simple Summary

Autologous blood doping (ABD) refers to the artificial increase in circulating red blood cell (RBC) mass by sampling, storage, and transfusion of one’s own blood. It is assumed that some athletes apply this prohibited technique to improve oxygen transport capacity and thus exercise performance. The primary aim of this study was to test whether RBC rheological and associated parameters significantly change due to ABD with the consideration of whether this type of measurement might be suitable for detecting ABD. Further, it was assessed whether those changes are translated into indices of endurance performance. Eight males underwent an ABD protocol combined with several blood parameter measurements and two exercise tests (pre and post transfusion). Results of this investigation suggest a change in the distribution of age-related RBC sub-populations and altered deformability of total RBC as well as of the respective sub-populations. Further, the identified changes in RBC also appear to improve sports performance. In conclusion, these data demonstrate significant changes in hematological and hemorheological parameters, which could be of interest in the context of new methods for ABD detection. However, additional research is needed with larger and more diverse study groups to widen the knowledge gained by this study.

Abstract

Autologous blood doping (ABD) refers to the transfusion of one’s own blood after it has been stored. Although its application is prohibited in sports, it is assumed that ABD is applied by a variety of athletes because of its benefits on exercise performance and the fact that it is not detectable so far. Therefore, this study aims at identifying changes in hematological and hemorheological parameters during the whole course of ABD procedure and to relate those changes to exercise performance. Eight healthy men conducted a 31-week ABD protocol including two blood donations and the transfusion of their own stored RBC volume corresponding to 7.7% of total blood volume. Longitudinal blood and rheological parameter measurements and analyses of RBC membrane proteins and electrolyte levels were performed. Thereby, responses of RBC sub-populations—young to old RBC—were detected. Finally, exercise tests were carried out before and after transfusion. Results indicate a higher percentage of young RBC, altered RBC deformability and electrolyte concentration due to ABD. In contrast, RBC membrane proteins remained unaffected. Running economy improved after blood transfusion. Thus, close analysis of RBC variables related to ABD detection seems feasible but should be verified in further more-detailed studies.

Nationwide analysis of cryopreserved packed red blood cell transfusion in civilian trauma

BACKGROUND

Liquid packed red blood cells (LPRBCs) have a limited shelf life and worsening quality with age. Cryopreserved packed red blood cells (CPRBCs) can be stored up to 10 years with no quality deterioration. The effect of CPRBCs on outcomes in civilian trauma is less explored. This study aims to evaluate the safety and efficacy of CPRBCs in civilian trauma patients.

METHODS

We analyzed the (2015-2016) Trauma Quality Improvement Program, including adult (age, ≥18 years) patients who received a RBC transfusion within 4 hours of admission. Patients were stratified, those who received LPRBC and those who received CPRBC. Primary outcomes were 24-hour and in-hospital mortality. Secondary outcomes were major complications. Propensity matching was performed adjusting for demographics, vitals, blood components, injury parameters, comorbidities, and center parameters.

RESULTS

A total of 39,975 patients were identified, and a matched cohort of 483 was obtained. A total of 161 received CPRBC (CPRBC, 2 [2-4]; plasma, 2 [0-5]; platelets, 1 [0-2]) and 322 received LPRBC (LPRBC, 3 [2-6]; plasma, 3 [0-6]; platelets, 1 [0-2]). The mean age was 43 ± 22 years, 62% were men, Injury Severity Score was 18 (12-27), and 65% had a blunt injury. Patients who received CPRBC had similar 24-hour mortality (1.8% vs. 2.3%; p = 0.82) and in-hospital mortality (4.9% vs. 5.2%; p = 0.88). No difference was found in terms of complications (15.3% vs. 17.2%; p = 0.21) between the two groups.

CONCLUSION

Transfusion of CPRBCs may be as safe and effective as transfusion of LPRBCs in moderately injured trauma patients. Cryopreservation has the potential to expand our transfusion armamentarium in diverse settings, such as periods of increased usage, disaster scenarios, and rural areas.

LEVEL OF EVIDENCE

Therapeutic study, level III.

Frozen Blood Reserves

Frozen blood reserves are an important component in meeting blood needs. The idea behind a frozen blood reserve is twofold: to freeze units of rare blood types for later use by patients with special transfusion needs and for managing special transfusion circumstances. The permeating additive glycerol is used as a cryoprotectant to protect red blood cells (RBCs) from freezing damage. The use of thawed RBCs has been hampered by a 24-h outdating period due to the potential bacterial contamination when a functionally open system is used for addition and removal of the glycerol. The introduction of an automated, functionally closed system for glycerolization and deglycerolization of RBCs improved the operational practice. More importantly, the closed process allowed for extended shelf life of the thawed RBCs. In the current chapter, a cryopreservation procedure for RBCs using a functionally closed processing system is described.

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.

Contemporary resuscitation of hemorrhagic shock: What will the future hold?

Resuscitation of the critically ill patient with fluid and blood products is one of the most widespread interventions in medicine. This is especially relevant for trauma patients, as hemorrhagic shock remains the most common cause of preventable death after injury. Consequently, the study of the ideal resuscitative product for patients in shock has become an area of great scientific interest and investigation. Recently, the pendulum has swung towards increased utilization of blood products for resuscitation. However, pathogens, immune reactions and the limited availability of this resource remain a challenge for clinicians. Technologic advances in pathogen reduction and innovations in blood product processing will allow us to increase the safety profile and efficacy of blood products, ultimately to the benefit of patients. The purpose of this article is to review the current state of blood product based resuscitative strategies as well as technologic advancements that may lead to safer resuscitation.

The effects of cryopreserved red blood cell transfusion on tissue oxygenation in obese trauma patients

BACKGROUND

Low tissue oxygenation (StO2) is associated with poor outcomes in obese trauma patients. A novel treatment could be the transfusion of cryopreserved packed red blood cells (CPRBCs), which the in vitro biochemical profile favors red blood cell (RBC) function. We hypothesized that CPRBC transfusion improves StO2 in obese trauma patients.

METHODS

Two hundred forty-three trauma patients at five Level I trauma centers who required RBC transfusion were randomized to receive one to two units of liquid packed RBCs (LPRBCs) or CPRBCs. Demographics, injury severity, StO2, outcomes, and biomarkers of RBC function were compared in nonobese (body mass index [BMI] < 30) and obese (BMI ≥ 30) patients. StO2 was also compared between obese patients with BMI of 30 to 34.9 and BMI ≥ 35. StO2 was normalized and expressed as % change after RBC transfusion. A p value less than 0.05 indicated significance.

RESULTS

Patients with BMI less than 30 (n = 141) and BMI of 30 or greater (n = 102) had similar Injury Severity Score, Glasgow Coma Scale, and baseline StO2. Plasma levels of free hemoglobin, an index of RBC lysis, were lower in obese patients after CPRBC (125 [72-259] μg/mL) versus LPRBC transfusion (230 [178-388] μg/mL; p < 0.05). StO2 was similar in nonobese patients regardless of transfusion type, but improved in obese patients who received CPRBCs (104 ± 1%) versus LPRPCs (99 ± 1%, p < 0.05; 8 hours after transfusion). Subanalysis showed improved StO2 after CPRBC transfusion was specific to BMI of 35 or greater, starting 5 hours after transfusion (p < 0.05 vs. LPRBCs). CPRBCs did not improve clinical outcomes in either group.

CONCLUSION

CPRBC transfusion is associated with increased StO2 and lower free hemoglobin levels in obese trauma patients, but did not improve clinical outcomes. Future studies are needed to determine if CPRBC transfusion in obese patients attenuates hemolysis to improve StO2.

LEVEL OF EVIDENCE

Therapeutic, level IV.

Previous Cryopreservation Alters the Natural History of the Red Blood Cell Storage Lesion

BACKGROUND

During storage, packed red blood cells (pRBCs) undergo a number of biochemical, metabolic, and morphologic changes, collectively known as the "storage lesion." We aimed to determine the effect of cryopreservation on the red blood cell storage lesion compared with traditional 4°C storage.

METHODS

Previously cryopreserved human pRBCs were compared with age-matched never-frozen pRBCs obtained from the local blood bank. The development of the red cell storage lesion was evaluated after 7, 14, 21, 28, and 42 days of storage at 4°C in AS-3 storage medium. We measured physiological parameters including cell counts, lactic acid, and potassium concentrations as well as signs of eryptosis including loss of phosphatidylserine (PS) asymmetry, microparticle production, and osmotic fragility in hypotonic saline.

RESULTS

Compared with controls, previously cryopreserved pRBC at 7 days of storage in AS-3 showed lower red cell counts (3.7 vs. 5.3 × 10 cells/μL, P < 0.01), hemoglobin (Hgb) (12.0 vs. 16.5 g/dL, P < 0.01), hematocrit (33.0% vs. 46.5%, P < 0.01), and pH (6.27 vs. 6.72, P < 0.01). Over 28 days of storage, storage cryopreserved pRBC developed increased cell-free Hgb (0.7 vs. 0.3 g/dL, P < 0.01), greater PS exposure (10.1% vs. 3.3%, P < 0.01), and microparticle production (30,836 vs. 1,802 MP/μL, P < 0.01). Previously cryopreserved cells were also less resistant to osmotic stress.

CONCLUSION

The red blood cell storage lesion is accelerated in previously cryopreserved pRBC after thawing. Biochemical deterioration of thawed and deglycerolized red cells suggests that storage time before transfusion should be limited to achieve similar risk profiles as never-frozen standard liquid storage pRBC units.

Damage Control Resuscitation for Catastrophic Bleeding

The timely recognition of shock secondary to hemorrhage from severe facial trauma or as a complication of complex oral and maxillofacial surgery presents formidable challenges. Specific hemostatic disorders are induced by hemorrhage and several extreme homeostatic imbalances may appear during or after resuscitation. Damage control resuscitation has evolved from massive transfusion to a more complex therapeutic paradigm that includes hemodynamic resuscitation, hemostatic resuscitation, and homeostatic resuscitation. Definitive control of bleeding is the principal objective of any comprehensive resuscitation scheme for hemorrhagic shock.

Quality Assessment of Established and Emerging Blood Components for Transfusion

Blood is donated either as whole blood, with subsequent component processing, or through the use of apheresis devices that extract one or more components and return the rest of the donation to the donor. Blood component therapy supplanted whole blood transfusion in industrialized countries in the middle of the twentieth century and remains the standard of care for the majority of patients receiving a transfusion. Traditionally, blood has been processed into three main blood products: red blood cell concentrates; platelet concentrates; and transfusable plasma. Ensuring that these products are of high quality and that they deliver their intended benefits to patients throughout their shelf-life is a complex task. Further complexity has been added with the development of products stored under nonstandard conditions or subjected to additional manufacturing steps (e.g., cryopreserved platelets, irradiated red cells, and lyophilized plasma). Here we review established and emerging methodologies for assessing blood product quality and address controversies and uncertainties in this thriving and active field of investigation.

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.

Evidence of benefits from using fresh and cryopreserved blood to transfuse patients with acute sickle cell disease

BACKGROUND

The transfusion of red blood cell (RBC) concentrates is the main treatment for acute vaso-occlusive symptoms in sickle cell disease (SCD). Units of packed RBCs (pRBCs) must retain optimal characteristics for transfusion throughout the storage period. Transfused RBCs interact with the plasma and the endothelium that lines blood vessels and may be the target of immune-hematologic conflict if the patient produces antibodies against RBCs. Questions remain concerning the benefit-risk balance of RBC transfusions, in particular about the shelf-life of the units.

STUDY DESIGN AND METHODS

Plasma samples from 33 hemoglobin SS patients with SCD who had severe acute-phase symptoms or were in steady-state were put in contact with 10 fresh-stored and older stored samples from the same 10 RBC units. The factors affecting RBC survival (phosphatidylserine exposure, cytosolic calcium influx, cell size reduction) were analyzed.

RESULTS

We show that the effects of plasma samples from patients with SCD on pRBCs depend on the clinical condition of the patients and the duration of red cell storage. Signs of RBC senescence were correlated with the clinical status of the patient from whom the plasma sample was obtained. A decrease in RBC size and an increase in phosphatidylserine exposure were correlated with the duration of RBC storage. The behavior of cryopreserved pRBCs was similar to that of fresh refrigerated RBCs when challenged with patient plasma samples.

CONCLUSION

The key points of this study are that the clinical condition of patients with SCD can negatively affect the integrity of pRBCs for transfusion, and those effects increase with longer storage. Also, cryopreserved pRBCs behave similarly to fresh RBCs when challenged with plasma samples from patients with SCD in acute phase. Our data provide the first evidence that fresh RBCs stored for short periods may be of greater benefit to patients with SCD than RBCs that have been refrigerated for longer periods, particularly for those who have acute symptoms of SCD.

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.

Continuous removal of glycerol from frozen-thawed red blood cells in a microfluidic membrane device

Cryopreservation of human red blood cells (RBCs) in the presence of 40% glycerol allows a shelf-life of 10 years, as opposed to only 6 weeks for refrigerated RBCs. Nonetheless, cryopreserved blood is rarely used in clinical therapy, in part because of the requirement for a time-consuming (∼1 h) post-thaw wash process to remove glycerol before the product can be used for transfusion. The current deglycerolization process involves a series of saline washes in an automated centrifuge, which gradually removes glycerol from the cells in order to prevent osmotic damage. We recently demonstrated that glycerol can be extracted in as little as 3 min without excessive osmotic damage if the composition of the extracellular solution is precisely controlled. Here, we explore the potential for carrying out rapid glycerol extraction using a membrane-based microfluidic device, with the ultimate goal of enabling inline washing of cryopreserved blood. To assist in experimental design and device optimization, we developed a mass transfer model that allows prediction of glycerol removal, as well as the resulting cell volume changes. Experimental measurements of solution composition and hemolysis at the device outlet are in reasonable agreement with model predictions, and our results demonstrate that it is possible to reduce the glycerol concentration by more than 50% in a single device without excessive hemolysis. Based on these promising results, we present a design for a multistage process that is predicted to safely remove glycerol from cryopreserved blood in less than 3 min.