Red blood cell transfusion practices in extracorporeal membrane oxygenation: A single-center study

Abstract

Objectives: Evaluating blood transfusion practices and their impact on morbidity and mortality across extracorporeal membrane oxygenation (ECMO) configurations.

Background: As ECMO becomes increasingly utilised in critical care, the ideal Hgb level remains uncertain. While guidelines recommend higher levels, emerging evidence suggests potential harm. Our study addresses this gap by investigating the optimal Hgb level for ECMO.

Methods: A retrospective cohort study included all adult patients receiving ECMO between January 2016 and December 2018. The primary outcome assessed the optimal Hgb level associated with reduced ECMO duration and in-hospital mortality. Multivariable and Cox-proportional regression analyses were performed.

Results: A total of 306 patients underwent ECMO, with 31 patients having mean Hgb levels 7-7.9 g/dL, 176 patients 8-8.9 g/dL, 72 patients 9-9.9 g/dL, and 27 patients ≥10 g/dL. The mean (SD) age was 56 years (15), with 60.8% male (186/306). ECMO configurations were primarily Venoarterial (VA) (59.8%), followed by Venovenous (VV) (36.9%) and Hybrid (3.3%). The 7-7.9 g/dL Hgb group was associated with longer ECMO duration (mean 17.5 days, coefficient 2.2, 95% CI 0.02-4.4, p = 0.048) compared to the ≥10 g/dL group, with no significant mortality differences across Hgb levels. VA ECMO patients had a significantly higher mortality risk than VV ECMO patients (aHR 2.33, 95% CI 1.50-3.60, p < 0.001). Blood product use, including RBC and Cryo, was associated with longer ECMO duration, while FFP reduced both duration (coefficient - 0.84, 95% CI -1.11--0.57, p < 0.001) and mortality risk (aHR 0.895, 95% CI 0.818-0.973, p = 0.012).

Conclusion: Targeting Hgb level >8 g/dL in ECMO patients may help reduce ECMO duration.

Keywords: ECMO; blood transfusion; length of stay; mortality.