Strategies to Reduce Diagnostic Blood Loss and Anemia in Hospitalized Patients: A Scoping Review

OBJECTIVES: Blood sampling is a recognized contributor to hospital-acquired anemia. We aimed to bundle all published neonatal, pediatric, and adult data regarding clinical interventions to reduce diagnostic blood loss. DATA SOURCES: Four electronic databases were searched for eligible studies from inception until May 2021. STUDY SELECTION: Two reviewers independently selected studies, using predefined criteria. DATA EXTRACTION: One author extracted data, including study design, population, period, intervention type and comparator, and outcome variables (diagnostic blood volume and frequency, anemia, and transfusion). DATA SYNTHESIS: Of 16,132 articles identified, we included 39 trials; 12 (31%) were randomized controlled trials. Among six types of interventions, 27 (69%) studies were conducted in adult patients, six (15%) in children, and six (15%) in neonates. Overall results were heterogeneous. Most studies targeted a transfusion reduction (n = 28; 72%), followed by reduced blood loss (n = 24; 62%) and test frequency (n = 15; 38%). Small volume blood tubes (n = 7) and blood conservation devices (n = 9) lead to a significant reduction of blood loss in adults (8/9) and less transfusion of adults (5/8) and neonates (1/1). Point-of-care testing (n = 6) effectively reduced blood loss (4/4) and transfusion (4/6) in neonates and adults. Bundles including staff education and protocols reduced blood test frequency and volume in adults (7/7) and children (5/5). CONCLUSIONS: Evidence on interventions to reduce diagnostic blood loss and associated complications is highly heterogeneous. Blood conservation devices and smaller tubes appear effective in adults, whereas point-of-care testing and bundled interventions including protocols and teaching seem promising in adults and children.