Immunomodulation / Storage Lesion

Summary In this retrospective single-center study Basran and colleagues demonstrate an association between red blood cell (RBC) storage time and increased short and long-term mortality, postoperative acute renal dysfunction (ARD) and increased intensive care unit (ICU) and hospital length of stay (LOS) in patients undergoing repeat cardiac surgery. 321 patients met their study criteria, which included patients undergoing repeat median sternotomy for coronary artery bypass graft or valve replacement surgery on cardiopulmonary bypass and who received allogeneic RBCs.

Summary Tinmouth and colleagues present an exhaustive review of laboratory and clinical studies examining the red cell storage lesion and its clinical consequences. They describe the biophysical and biochemical changes that take place during storage including red cell shape change and loss of deformability, increased adhesion to the endothelium, and the accumulation of free hemoglobin and other bioreactive substances in the supernatant. These changes, they suggest, raise questions about this blood’s ability to negotiate the microcirculation and effectively deliver oxygen to the tissues.

Summary This experimental study by Gonzalez and colleagues demonstrated that transfusion of stored blood had a negative effect on microcirculatory hemodynamics and tissue oxygenation. To compared the effects of fresh and stored blood the investigators used the cremaster muscle flap in rats and measured vessel diameter, red blood cell (RBC) velocity, functional capillary density, granulocyte and lymphocyte behavior, RBC morphology, tissue oxygenation and temperature, oxygen saturation, tissue hypoxia and inflammation in 6 experimental groups.

Summary This study by Cabrales, using a hamster window chamber model, found that the transfusion of red blood cells (RBCs) with reduced deformability severely compromised microvascular flow and reduced functional oxygen delivery. It has been reported that, in storage, RBCs lose their flexibility and deformability raising questions about their ability, when transfused, to negotiate the microcirculation where capillary diameter is smaller than the diameter of the RBCs. This experimental study investigated the effects of less flexible RBCs on microvascular perfusion and tissue oxygenation.

Summary In this ex vivo study, Escobar and colleagues investigate the inflammatory effect of transfusing stored red blood cells (RBCs), specifically their inflammatory generating effect in the recipient’s circulating leukocytes. The authors refer to work demonstrating that bioactive substances such as cytokines and proinflammatory lipids accumulate during storage. These cytokines, they suggest, can be reduced by leukocyte filtration, but not the proinflammatory lipids.

Summary This study looked at the effects of routine cold storage and gamma irradiation on the flow properties of red blood cells (RBCs). Specifically, the investigators measured effects on RBC deformability (the ability of RBCs to flex and change their shape), RBC aggregability (the ability of RBCs to aggregate or collect into a cluster) and RBC adherence to endothelial cells. Alterations in these flow properties can impede microcirculatory flow. Blood was withdrawn from healthy volunteers and stored as per practice at the authors’ institution’s blood bank. Blood was not leukoreduced.

Summary Since 2003, transfusion-related acute lung injury (TRALI) has become the most common cause of death for patients receiving blood transfusions. Signs of TRALI include acute dyspnea with hypoxia and new or worsening pulmonary infiltrates appearing within a few hours of transfusion of plasma, cellular blood components, or immunoglobulin. Because these signs/symptoms overlap with other lung dysfunctions, a definitive diagnosis at the bedside is not always possible.

Summary [Transfusion-related acute lung injury (TRALI) is an often fatal complication of blood transfusion, with a mortality rate of 5-25%. The condition is characterized by oxidative stress and the storage duration of blood products is implicated in its etiology. Stored, leukoreduced packed red blood cells (PRBCs) have a shelf life of 42 d, but after day 21, plasma from PRBCs primes polymorphonuclear leukocytes to cause endothelial damage, capillary leak, and TRALI.

Abstract

Abstract

BACKGROUND:

Transfusion of blood components may increase the risk of complications in relation to surgery. During storage, red blood cells (RBCs) undergo structural and functional changes that may reduce function and viability after transfusion. The aim of the study was to evaluate the quality of buffy-coat reduced red cells in SAG-M additive solution, by assessing biomarkers of oxidative and inflammatory stress during a storage period of 35 days.

STUDY DESIGN AND METHODS: