Liberal or Restrictive Transfusion Strategy in Patients with Traumatic Brain Injury

In critically ill patients with traumatic brain injury, the impact of a liberal red blood cell (RBC) transfusion strategy as compared with a restrictive transfusion strategy on neurological functional outcomes is unclear.   

The HEMOglobin Transfusion Threshold in Traumatic Brain Injury OptimizatioN (HEMOTION) trial was an international, pragmatic, randomised, open label blinded-endpoint clinical trial where adults with moderate or severe traumatic brain injury and anaemia were randomised 1:1 to receive a liberal RBC transfusion (Hb threshold of ≤100 g/L) or a restrictive transfusion (Hb threshold of ≤70 g/L).   

Red cells were given a single unit at a time, when the specified Hb threshold was met, until ICU discharge. Patients with active life-threatening bleeding at the time of randomisation (with either haemorrhagic shock or requiring an urgent surgical procedure) were excluded.  

The primary outcome was an unfavourable outcome at six months, as assessed with the Glasgow Outcome Scale–Extended, with the trial powered to detect an absolute difference of 10 percentage points between the two groups. Secondary outcomes examined at six months comprised of mortality, functional independence, quality of life, and depression. 

A total of 742 patients were randomised between 1 September 2017, and 13 April 2023. There was clear separation between the two groups in achieving the target Hb levels. Unfavourable outcomes occurred in 68.4% (249/364) of patients in the liberal arm and 73.5% (263/358) of patients in the restrictive arm (adjusted absolute difference, restrictive strategy vs liberal strategy, 5.4 percentage points; 95% CI, -2.9 to 13.7).   

With respect to the secondary outcomes, there was no correlation between the transfusion strategy and mortality or depression. However, patients within the liberal transfusion group displayed higher scores on some of the scales that examined functional independence and quality of life.   

Overall, the findings from this trial revealed that a liberal transfusion strategy did not reduce the risk of an unfavourable outcome at six months in critically ill patients with traumatic brain injury and anaemia. Further studies are required to understand the findings from the secondary outcomes.   

 Reference 

Turgeon AF et al. Liberal or Restrictive Transfusion Strategy in Patients with Traumatic Brain Injury. New England Journal of Medicine; Published June 13, 2024.  https://www.nejm.org/doi/10.1056/NEJMoa2404360