Utilization of Intravenous Iron Therapy and Red Blood Cell Transfusion in Emergency Department Patients with Anemia: A Single-Center Retrospective Cohort Study

Background/Objectives: Anemia is frequently encountered in emergency departments (EDs). Although intravenous (IV) iron can be used as an alternative or adjunct to red blood cell (RBC) transfusion in selected hemodynamically stable patients, its use in the ED remains limited. This study described IV iron utilization and RBC transfusion patterns in ED patients with anemia and evaluated their associations with clinical outcomes. Methods: We conducted a single-center retrospective cohort study of patients who presented to a tertiary ED with hemoglobin (Hb) ≤ 10 g/dL between January 2019 and December 2021. Patients were categorized according to receipt of IV iron in the ED. Baseline characteristics, laboratory findings, transfusion practice, hospital length of stay (LOS), ICU admission, and in-hospital mortality were compared between groups. Results: Among 3340 patients, 89 (2.7%) received IV iron in the ED. IV iron recipients were older and had lower Hb levels than non-recipients. Gastrointestinal disorders were more frequent in the IV iron group (68.5% vs. 19.9%), and IV iron was commonly administered with ED RBC transfusion. ED transfusion (69.7% vs. 11.1%) and ICU admission (24.7% vs. 15.7%) were more frequent in the IV iron group. Among patients with available ferritin and transferrin saturation (TSAT), IV iron recipients had lower ferritin levels and more frequently showed ferritin-based or combined ferritin/TSAT findings suggestive of iron deficiency. In-hospital mortality was similar between groups (5.6% vs. 5.7%). Among hospitalized patients, median LOS was shorter in the IV iron group than in the non-IV iron group (6.6 vs. 9.7 days). Conclusions: IV iron was infrequently administered in ED patients with Hb ≤ 10 g/dL and was used mainly as an adjunct to RBC transfusion in older patients with gastrointestinal causes of anemia. Its association with shorter LOS should be interpreted cautiously. Structured ED-based anemia evaluation may help optimize IV iron use in selected patients.