Mechanism and Repository Study for the Red Cell Storage Duration Study

A large multicenter randomized controlled trial of approximately 1700 critically ill patients' status post complex cardiac surgery with sternotomy, called the Red Cell Storage Duration Study (RECESS), is currently ongoing. In the RECESS trial, study groups are randomized to either RBCs of less than or equal to 10 days storage time or to greater than or equal to 21 days. The primary outcome of RECESS is a change in multiple organ dysfunction score. Secondary outcomes in RECESS include all cause 28-day mortality, mechanical ventilation free days, and other clinical outcomes. The RECESS study presents a unique opportunity to investigate mechanisms associated with RBC storage duration in the context of clinical outcomes for well-characterized surgical study groups. The ancillary study described here is called the Mechanism and Repository Study (MARS) for RECESS. The MARS study will analyze the most commonly reported and hypothesized mechanisms considered to be associated with the RBC storage lesion and adverse outcomes in critically ill patients. Laboratories with expertise in RBC function, nitric oxide mechanisms, the coagulation cascade, microparticle analysis and immunology will each examine hypotheses addressing mechanisms potentially able to relate storage time to clinical outcomes in RBC transfusion recipients. At the conclusion of the study, the results will provide a much better understanding of how RBC storage age affects recipient RBC function, coagulation parameters, microparticle load and immune modulation. Perhaps most importantly, this study will also develop a large sample repository for future analysis.