Red blood cell transfusion for critically ill patients admitted through the emergency department in South Korea.

Background: Red blood cells (RBCs) are a limited resource, and the adverse effects of transfusion must be considered. Multiple randomized controlled trials on transfusion thresholds have been conducted, leading to the establishment of a restrictive transfusion strategy. This study aimed to investigate the status of RBC transfusions in critically ill patients.

Methods: This cohort study was conducted at five university hospitals in South Korea. From December 18, 2022, to November 30, 2023, 307 nontraumatic, anemic patients admitted to intensive care units through the emergency departments were enrolled. We determined whether patients received RBC transfusion, transfusion triggers, and the clinical results.

Results: Of the 154 patients who received RBC transfusions, 71 (46.1%) had a hemoglobin level of 7 or higher. Triggers other than hemoglobin level included increased lactate levels in 75 patients (48.7%), tachycardia in 47 patients (30.5%), and hypotension in 46 patients (29.9%). The 28-day mortality rate was not significantly reduced in the group that received transfusions compared to the non-transfusion group (21.4% vs. 26.8%, P=0.288). There was no difference in the intensive care unit and hospital length of stay or the proportion of survival to discharge between the two groups. The prognosis showed the same pattern in various subgroups.

Conclusions: Despite the large number of RBC transfusions used in contradiction to the restrictive strategy, there was no notable difference in the prognosis of critically ill patients. To minimize unnecessary RBC transfusions, the promotion of transfusion guidelines and research on transfusion criteria that reflect individual patient conditions are required.