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Red blood cell exchange (RBCEx) has become a standard therapy to remove abnormal red blood cells (RBCs) in patients with sickle cell disease (SCD). In the last few decades, numerous RBCEx procedures have been performed chronically during regular programs, while numerous procedures have also been performed in an emergency for several indications, this therapeutic option being very efficient in vital and emergency situations. In both groups of indications, large amounts of sickle RBCs have to be removed, which requires great precision and the setting of specific hematological targets. The aim of this review is to discuss the aims, clinical and biological targets, and the requirements and precautions when performing RBCEx in an emergency. Moreover, we analyze how improvement of the techniques as well as the clinical and biological targets has led to optimization of the procedures in emergency settings. We also consider the outstanding issues that require additional investigation., (Copyright © 2020. Published by Elsevier Ltd.)

Background: Chronic red blood cell exchanges (RBCXs) are frequently used to prevent complications in patients with sickle cell anemia, but the scarcity of matched red blood cell packs (RBCPs) is a serious concern. The main goal of this study was to compare the number of RBCPs used during RBCXs between the Spectra Optia (SO) device (with the automatic depletion step) and the former Cobe Spectra (CSP) device., Study Design and Methods: The performances and safety of 300 SO sessions using the automatic depletion step (SO/DE) in 50 patients with sickle cell anemia under a chronic transfusion program over a 1-year period were prospectively analyzed. The numbers of RBCPs saved using this protocol compared to the SO device without depletion and to the CSP device were determined., Results: The SO/DE protocol appeared to be safe, as only 5% and 17% of the sessions were characterized by a significant decrease in blood pressure and increase in heart rate (grade 2 adverse events), respectively. Postapheresis hematocrit and fraction of cells remaining reached expected values. The SO/DE protocol required 16% fewer RBCPs compared to SO without depletion, allowing a mean saving of 12 RBCPs per patient and per year and 13% fewer compared to CSP device. Interestingly, the saving was more important for patients with high total blood volume and/or high preapheresis hematocrit., Conclusion: The SO/DE protocol is an efficient, safe and cost-effective procedure for patients with sickle cell anemia under a chronic transfusion program., (© 2019 AABB.)

Red blood cell exchange (RBCX) has become a standard therapy to remove abnormal red blood cells (RBC) in patients with sickle cell disease (SCD). In the last few decades, RBCX techniques have gradually improved, allowing sickle RBCs to be removed with greater precision and enabling specific hematological targets to be set. Improved knowledge of the techniques as well as the clinical and biological targets has led to optimization of the procedures. The aim of this review is to summarize the current technique, methods, targets and schedules of RBCX and to consider the outstanding issues that require additional investigation., (Copyright © 2019. Published by Elsevier Ltd.)

Erythrocytapheresis procedures, increasingly used in the management of patients with severe complications of sickle cell disease, are limited by adequate venous access. We have successfully used short-term femoral catheter insertion, during a 6.5-year period for a total of 443 procedures, to perform long-term erythrocytapheresis in 18 consecutive children with sickle cell disease., (Copyright © 2013 Mosby, Inc. All rights reserved.)

Background: Hypoxia is a major cause of painful vaso-occlusive crisis in sickle cell disease (SCD). Simple transfusion and red blood cell (RBC) exchange are commonly used as preventive therapies whose aim is to dilute hemoglobin (Hb)S-containing RBCs (SS-RBCs) with normal RBCs (AA-RBCs) to prevent sickling. We hypothesized that the effectiveness of transfusion could be improved by the encapsulation of inositol hexaphosphate (IHP), an allosteric Hb effector, in transfused AA-RBCs. Indeed, apart from their diluting effect on SS-RBCs, IHP-loaded RBCs (IHP-RBCs) with increased oxygen release capacity could palliate in vivo oxygen deprivation and reduce sickling., Study Design and Methods: The study was designed to investigate the therapeutic effect of IHP-RBCs transfusion on in vitro sickling of SS-RBCs collected from 20 SCD patients. Patients' RBCs were diluted with various proportions of IHP-RBCs or AA-RBCs (processed or stored RBCs as controls). Resulting suspensions were subjected to deoxygenation followed by partial reoxygenation at 5% oxygen. Sickling was evaluated by microscopy., Results: Stored RBCs (50% dose) used to mimic simple transfusion exhibited a poor antisickling effect (5.6%) and a low response rate (65%). In contrast, IHP-RBCs treatment was seven times more effective resulting in 35% of sickling reduction and a 94% response rate. Sickling was inhibited in a dose-dependent manner: 9.9, 25.1, and 35.0% for IHP-RBCs in percentages of 10, 30, and 50%, respectively., Conclusion: Our results indicate that IHP-RBCs prevent in vitro sickling and suggest that it could improve conventional transfusion therapy in terms of transfused volume, frequency, and efficacy., (© 2010 American Association of Blood Banks.)

Patients receiving high-dose cyclophosphamide as a conditioning regimen for peripheral stem cell collection are subjected over a short period of time to significant exposure to reactive oxygen species (ROS). All these patients undergo profound leucopenia. Various other short-term toxicities are observed in a fraction of the patients, including febrile aplasia requiring hospitalization, thrombocytopenia and mucositis. Although stem cell collection is feasible in the majority of patients stimulated with haematopoietic growth factors, in some instances, graft collection cannot be performed because of insufficient concentrations of stem cells in peripheral blood. There is currently no predictive assay to determine which patients treated with high-dose cyclophosphamide have a high risk of febrile aplasia or will successfully undergo cytaphereses for stem cell collection. In order to identify such predictive factors, we analysed the level of expression before treatment of various ROS detoxification mechanisms in the peripheral blood of 37 patients receiving high-dose cyclophosphamide for lymphoproliferative diseases. Various parameters involved in the metabolism of ROS were measured in plasma and/or erythrocytes, including superoxide dismutase, glutathione, glutathione peroxidase, glutathione reductase and malondialdehyde. High levels of erythrocyte superoxide dismutase before cyclophosphamide therapy were correlated with an increased risk of hospitalization for febrile aplasia (65% vs. 29%, P = 0.013). High superoxide dismutase and low erythrocyte glutathione reductase were associated with lower CD34 yields. These data suggest that components of the ROS detoxification system modulate the degree of short-term toxicity of cyclophosphamide and could be used as predictive markers in individual patients.

Automatic red blood cell exchange i.e. using devices (RBCX) has become a standard therapy to remove abnormal red blood cells (RBC) in adults and children affected by sickle cell disease (SCD). This treatment is performed both in emergency to treat acute complications and through a regular program of RBCX to prevent the recurrence of complications. However, small children, i.e. those with a low body weight, height and total blood volume, are at risk of relative hypovolemia and metabolic complications during the procedure. Moreover, the peripheral venous access is limited among young children, which requires alternative short- or long-term venous access. These two main limiting factors necessitate adaptations of the procedures and subsequent monitoring during and after the sessions. However, performing RBCX in children requires other adaptations and cautions that must be considered. Our review summarizes the limits, safety precautions and the adaptations of the techniques to ensure RBCX in children. [ABSTRACT FROM AUTHOR]