In-hospital stay of anemic patients in the ED with/without transfusion: a single-center propensity-matched study.

Background: Anemia affects up to 25% of emergency department (ED) patients. Restrictive red blood cell (RBC) transfusion strategies are recommended for stable patients, but ED transfusion practices often remain liberal. Benefits of ED transfusion remains unclear.

Objective: To evaluate the impact of ED transfusion on death-adjusted in-hospital length of stay (LOS) in stable anemic patients requiring hospitalization.

Methods: This single-center retrospective propensity-matched study included patients ≥ 18 years admitted to the ED of Nîmes University Hospital in 2022 with hemoglobin levels between 70 and 90 g.L^- 1. Patients with hemorrhagic shock or requiring emergent hemostatic procedures were excluded. Propensity score matching was conducted on variables including age, comorbidities, hemoglobin levels, and diastolic blood pressure. Primary outcome was adjusted in-hospital LOS. Secondary outcomes included ED LOS and RBC transfusion volumes.

Results: Among 564 patients, 118 (21%) were propensity-matched: 59 (50%) ED-transfused, 59 (50%) non-ED-transfused. Adjusted in-hospital LOS 13 [8-32] for ED-transfused patients and 12 [6-24] days for non-ED-transfused patients (median difference = 0; 95%CI: -10-7; p = 0.52). Median difference in ED LOS was 7:13 (95%CI: 1:00-11:25; p < 0.001) between ED transfused and non-ED-transfused patients. Median difference in number of RBC transfused during in hospital stay was 2 (95%CI: 1-3); p < 0.01) between ED transfused and non-ED-transfused patients.

Conclusion: In stable anemic patients with 70 to 90 g.L^- 1 hemoglobin level, ED transfusion did not reduce adjusted in-hospital LOS but prolonged ED LOS. Identifying patients who may safely defer transfusion could improve ED efficiency and safety.