Rapid bedside rejuvenation of red blood cell with an autologous cell salvage device

Background and Objectives

During storage, red blood cells (RBCs) undergo physicochemical changes which affect the quality, function, and in vivo survival of transfused packed RBCs (pRBC). Changes include decreased 2,3‐diphosphoglycerate (2,3‐DPG) levels, decreased ATP, changes in mechanical properties and oxidative injury. RBC rejuvenation is a method used to increase levels of 2,3‐DPG and ATP in pRBCs. This process requires incubating the pRBCs with a rejuvenation solution and subsequent washing. Standard blood bank protocols using the COBE 2991 Cell Processor require several hours of preparation. The objective of this study was to verify if a bedside protocol for rejuvenating pRBC and washing with the Sorin Xtra autologous cell salvage system could be used.

Materials and Methods

Outdated pRBC units were obtained and rejuvenated in a model operating suite using a dry air incubator for 1 h at 37°C. Six units of pRBCs were pre‐diluted with saline (1000 ml) and six units were not pre‐diluted with saline. All units were washed with normal saline (1000 ml) using an apheresis‐design cell salvage device in manual mode and wash volume set to 3000 ml. Samples were collected and analyzed for standard RBC quality parameters at baseline and post‐wash.

Results

Total pRBC wash efficiency was 94% ± 12% at a final hematocrit of 67.7 ± 5.9% while maintaining post‐wash hemolysis 0.24 ± 0.12 %. Pre‐dilution prior to washing did not confer statistically significant differences in final RBC quality parameters with the notable exceptions of calculated hemolysis and supernatant potassium levels (P < 0.05). The washing process can be completed within 10 min. The post‐wash RBC parameters are appropriate for immediate transfusion to patients.     

Recombinant erythropoietin as alternative to red cell transfusion in sickle cell disease

Disturbances in the physiological regulation of erythropoietin (EPO) in patients with sickle cell disease (SCD) may contribute to worsening anaemia and increased transfusion requirements, but the use of recombinant EPO in this group of patients is controversial. The objective of this study was to evaluate the use of this drug in adult patients with SCD and its effects on haemoglobin levels and transfusion requirements. We conducted a retrospective analysis at the University of Campinas, with nineteen adults with a diagnosis of SCD (HbSS and HbS/β⁺ thalassaemia), who had received at least 1 year of EPO therapy between 2007 and 2014. Haemoglobin concentrations and trends of variation in transfused RBC volumes were compared before and after EPO administration. We observed that seven patients had a good response to treatment (Hb increment higher than 1·5 g/dl) and nine had a partial response (0·5–1·5 g/dl increment) and there was a significant decrease in the need for transfusion amongst those who usually required regular transfusions. There were no increases in the rates of vaso‐occlusive crisis or venous thromboembolism in comparison to the year before the onset of the therapy. Erythropoietin therapy led to a marked increase in haemoglobin concentration with a concomitant decrease in the demand for transfusion. Considering all complications related to allogeneic transfusion, we believe that EPO therapy represents an important therapeutic tool in sickle cell anaemia.     

In vitro combinations of red blood cell,plasma and platelet components evaluated by thromboelastography

Background

Thromboelastography is increasingly used to evaluate coagulation in massively bleeding patients. The aim of this study was to investigate how different combinations of blood components affect in vitro whole blood clotting measured by thromboelastography.

Materials and methods

Packed red blood cells, plasma and platelets from fresh and old blood components were mixed in vitro, in proportions of 4:4:1, 5:5:2, 8:4:1 and 2:1:0, and analysed with thromboelastography. For the ratio 4:4:1 the experiment was done at both 37 °C and 32 °C.

Results

Thromboelastography curves were within normal reference values for the blood component proportions of 4:4:1 and 5:5:2. For 8:4:1, the angle and maximal amplitude were reduced below normal values, indicating low levels of fibrinogen and/or platelets. For the 2:1:0 proportion, all parameters were affected resulting in severely impaired in vitro clot formation. The reaction-time, reflecting the coagulation factor-dependent, initial clot formation, was slightly increased at a low temperature. Prolonged storage of the components did not affect the curve.

Discussion

With the introduction of guidelines on the management of massive bleeding it is important to have tools for the assessment of the new protocols. In vitro evaluation of mixtures of packed red blood cells, plasma and platelets by thromboelastography may be relevant in the prediction of in vivo clot formation and haemostasis.     

A shared regulatory perspective on deferral from blood donation of men who have sex with men (MSM)

National Regulatory Authorities (NRAs) establish deferral criteria for donors with risk factors for transfusion transmissible infections (TTI). In most jurisdictions, epidemiological data show that men who have sex with men (MSM) have a significantly higher rate of TTI than the general population. Nevertheless, changes from an indefinite donor deferral for MSM have been considered in many countries in response to concerns over a perceived discrimination and questioning of the scientific need. Changes to MSM donor deferral criteria should be based on sound scientific evidence. Safety of transfusion recipients should be the first priority, and stakeholder input should be sought.     

A study of blood transfusion services at a district hospital in Malawi

Background and objectives Severe anaemia is an important cause of mortality in developing countries. However, few studies have explored the use of and possibilities for blood transfusion services. The aims of this study are to explore the use of blood transfusion services at a hospital in sub‐Saharan Africa and to assess the quality of the transfusion services according to WHO guidelines. Materials and methods Patient age, gender, haemoglobin (Hb) level, diagnosis, hospital department and replacement donations were recorded for all blood transfusions administered at a district hospital in Malawi in January 2010. The laboratory equipment and procedures were scored according to WHO guidelines. Results The mean Hb of transfused patients was 4·8 g/dl. Fifty‐seven per cent (59/104) of the transfusions were given to children diagnosed with malaria, and 17% (18/104) were given to pregnant women. During the study period, blood was in stock and available for transfusion within 1 h of requisition. The equipment and procedures at this hospital met the main criteria for an adequate WHO stage of development. Conclusion In contrast to the advanced transfusion medicine in developed nations, our findings highlight the persistent and urgent need for life‐saving blood transfusions in especially young children and pregnant women in Africa. The results indicate that blood transfusion services adapted to local conditions may be a realistic solution for providing safe blood products in developing countries. Serious challenges, such as HIV transmission and sustainable organization of low‐risk blood donations should be addressed to assure access to safe blood products.     

Haemoglobin glycation (Hb1Ac) increases during red blood cell storage: a MALDI‐TOF mass‐spectrometry‐based investigation

Haemoglobin A_1c (HbA_1c) represents a key biomarker in diabetes diagnosis and management, as it is indicative of recent blood glucose concentrations. Glycation of haemoglobin is a non‐enzymatic irreversible process that is promoted by the prolonged exposure of erythrocytes to high glucose concentrations, a condition that is known to occur under blood banking conditions. However, controversial data indicate no clear hint as to whether and to which extent HbA_1c accumulates during red blood cell storage. Hereby, we propose the application of a validated MALDI‐TOF mass‐spectrometry‐based method to this issue and report the observation about HbA_1c levels apparently increasing over storage progression.     

Changes in circulating inflammatory markers following febrile non‐haemolytic transfusion reactions to leucoreduced red cells

It would be desirable to be able to distinguish fever as a result of febrile non‐haemolytic transfusion reactions (FNHTR) from other febrile conditions. To further characterize the inflammatory feature of FNHTR, we measured a large panel of inflammatory markers in pre‐ and posttransfusion plasma samples from patients with and without FNHTR following the transfusion of leucoreduced red blood cells. As FNHTR patients only displayed a significant increase in IL‐6, we conclude that changes in plasma cytokine levels during FNHTR are unlikely to be used diagnostically. An incidental finding of a distinct cytokine pattern in pretransfusion samples from FNHTR patients warrants further investigations, as it might be used to characterize the nature of FNHTR and to predict the risk of these adverse events.