Is red blood cell rheology preserved during routine blood bank storage?

BACKGROUND: Red blood cell (RBC) units stored for more than 2 weeks at 4°C are currently considered of impaired quality. This opinion has primarily been based on altered RBC rheologic properties (i.e., enhanced aggregability, reduced deformability, and elevated endothelial cell interaction), during prolonged storage of nonleukoreduced RBC units. In this study, the rheologic properties and cell variables of leukoreduced RBC units, during routine blood bank storage in saline‐adenine‐glucose‐mannitol, were investigated. STUDY DESIGN AND METHODS: Ten leukoreduced RBC units were stored at the blood bank for 7 weeks at 4°C. RBCs were tested weekly for aggregability, deformability, and other relevant variables. RESULTS: RBC aggregability was significantly reduced after the first week of storage but recovered during the following weeks. After 7 weeks aggregability was slightly, but significantly, reduced (46.9 ± 2.4‐44.3 ± 2.2 aggregation index). During storage the osmotic fragility was not significantly enhanced (0.47 ± 0.01% phosphate‐buffered saline) and the deformability at shear stress of 3.9 Pa was not significantly reduced (0.36 ± 0.01 elongation index [EI]). The deformability at 50 Pa was reduced (0.58 ± 0.01‐0.54 ± 0.01 EI) but remained within reference values (0.53 ± 0.04). During 5 weeks of storage, adenosine triphosphate was reduced by 54% whereas mean cell volume, pH, and mean cell hemoglobin concentration were minimally affected. CONCLUSIONS: RBC biochemical and physical alterations during storage minimally affected the RBC ability to aggregate and deform, even after prolonged storage. The rheologic properties of leukoreduced RBC units were well preserved during 7 weeks of routine blood bank storage.     

Patient blood management and blood conservation – Complimentary concepts and solutions for blood establishments and clinical services in South Africa and beyond

Blood transfusions come with risks and high costs, and should be utilized only when clinically indicated. Decisions to transfuse are however not always well informed, and lack of clinician knowledge and education on good clinical transfusion practices contribute to the inappropriate use of blood. Low and middle-income countries in particular take much strain in their efforts to address blood safety challenges, demand-supply imbalances, high blood costs as well as high disease burdens, all of which impact blood usage and blood collections. Patient blood management (PBM), which is a patient-focused approach aimed at improving patient outcomes by preemptively diagnosing and correcting anaemia and limiting blood loss by cell salvage, coagulation optimization and other measures, has become a major approach to addressing many of the challenges mentioned. The associated decrease in the use of blood and blood products may be perceived as being in competition with blood conservation measures, which is the more traditional, but primarily product-focused approach. In this article, we hope to convey the message that PBM and blood conservation should not be seen as competing concepts, but rather complimentary strategies with the common goal of improving patient care. This offers opportunity to improve the culture of transfusion practices with relief to blood establishments and clinical services, not only in South Africa and LMICs, but everywhere. With the COVID-19 pandemic impacting blood supplies worldwide, this is an ideal time to call for educational interventions and awareness as an active strategy to improve transfusion practices, immediately and beyond.     

Should the blood pressure or the blood vessel be the target of therapy?

Measured blood pressure is an insensitive and moderately nonspecific guide to the presence of vascular or cardiac diseases likely to progress to cardiovascular morbid events. Since the goal of the diagnosis and treatment of hypertension is to prevent or forestall such morbid events, blood pressure measurements should be supplemented by studies of the health of the cardiovascular system in defining the syndrome of hypertension and in monitoring its response to therapy.     

Should the blood pressure or the blood vessel be the target of therapy?

Measured blood pressure is an insensitive and moderately nonspecific guide to the presence of vascular or cardiac diseases likely to progress to cardiovascular morbid events. Since the goal of the diagnosis and treatment of hypertension is to prevent or forestall such morbid events, blood pressure measurements should be supplemented by studies of the health of the cardiovascular system in defining the syndrome of hypertension and in monitoring its response to therapy.