Lower versus higher hemoglobin threshold for transfusion in ARDS patients with and without ECMO

Area of Science:

• Critical Care Medicine
• Hematology
• Respiratory Medicine

Background:

• The optimal hemoglobin threshold for red blood cell (RBC) transfusions in adults with acute respiratory distress syndrome (ARDS) remains unclear.
• This study investigated the safety and efficacy of different transfusion thresholds in ARDS patients.

Purpose of the Study:

• To assess the impact of two distinct hemoglobin transfusion thresholds on short-term outcomes in adult patients diagnosed with ARDS.
• To compare a lower threshold (hemoglobin ≤ 8 g/dl) against a higher threshold (hemoglobin ≤ 10 g/dl).

Main Methods:

• A propensity score-matched analysis was conducted on 192 patients from a cohort of 1044 ARDS patients.
• Patients were stratified into a lower-threshold group (transfused at ≤ 8 g/dl hemoglobin) and a higher-threshold group (transfused at ≤ 10 g/dl hemoglobin).
• Primary endpoint was 28-day mortality; secondary endpoints included ventilator-free days and organ dysfunction composites.

Main Results:

• No significant difference in 28-day mortality was observed between the lower-threshold (36.5%) and higher-threshold (39.5%) groups (HR, 0.94; 95% CI, 0.59-1.48).
• Patients in the lower-threshold group received fewer RBC units and had lower ICU hemoglobin levels.
• A significantly lower chance of successful ventilator weaning within 28 days was noted in the lower-threshold group (SHR, 0.36; 95% CI, 0.15-0.86).

Conclusions:

• Transfusing RBCs at a hemoglobin threshold of 8 g/dl, compared to 10 g/dl, is not associated with increased 28-day mortality in ARDS patients.
• A lower transfusion threshold of 8 g/dl in ARDS patients was associated with a decreased likelihood of successful weaning from mechanical ventilation.