SINGLE VERSUS MULTIPLE RED BLOOD CELL UNIT TRANSFUSION STRATEGIES

Abstract

Historical practice supported the transfusion of multiple units of red blood cells (RBCs) successively. Recent recommendations from transfusion medicine experts now support transfusion of single units of RBCs with reassessment before transfusing successive units. Two systematic reviews of the literature were performed to determine if A) transfusion guidelines and review articles recommended either strategy and B) if studies directly support the benefit of transfusion. A lack of concordance in recommendations in the published literature was found and in addition to a lack of evidence supporting single unit transfusion strategies. A survey of transfusion medicine experts demonstrated that while most agreed on single unit transfusion strategies for stable inpatients, variability in practice was seen in outpatients and patients with comorbidities. Common elements were seen in what constitutes reassessment which may be useful to practicing clinicians. A conceptual flow diagram was developed to outline the factors that might influence the decision to use a single or multiple unit transfusion strategy and outcomes important to assess. The flow diagram was then used to guide an exploratory analysis to determine if defining single and multiple unit cohorts retrospectively, baseline characteristics could be collected, and to determine what outcomes could be assessed. This then led to the design of a retrospective study that would assess: In adult (age ≥18) inpatients at tertiary care hospitals in HHS and SJHH between January 1, 2010 to December 31, 2016 who were transfused RBCs during their first hospitalization, is there a difference in the gap time between the first and second transfusion episode depending on whether the patient was transfused a single unit or multiple units during their first transfusion episode? The findings from this study may be hypothesis generating to develop future prospective studies to determine if single unit transfusion strategies have benefit.