The Impact of Red Cell Age on Product Utilization in the Chronically Transfused Outpatient Population

In this study, the investigators will be evaluating the impact of red blood cell age in patients receiving chronic blood transfusions in the outpatient setting. This study will have a double-bind, randomized trial design, meaning that the investigators and participants will not be told the group assignment at study enrollment. Study participants will be randomly divided into two groups (50% of participants in each group) by a computer generated block randomization schema. The 'fresh blood' group will receive blood units that are 7 or less from the time of donor collection, and the 'aged blood' group will receive blood units that are greater than 21 to 42 days from the time of donor collection. The number of units of blood transfused will be decided based on the participant's hemoglobin level before blood transfusion. The primary goal of our study is to compare annual red blood cell product use (the number of units given per patient in a year). The investigators will also be comparing groups to evaluate the transfusion reaction frequency, iron burden (based on the level of ferritin in the blood), overall transfusion and care cost difference, and participant time spent in outpatient departments. Our hypothesis is that use of fresh blood in chronically transfused patients will lead to a decrease the in red cell transfusion rate, with subsequent clinical benefits including reduction of transfusion reaction frequency and systemic iron burden. This study will be taking place within the Calgary Zone of Alberta Health Services only.