Liberal Versus Restrictive Blood Transfusion Strategies in Neurocritical Care: A Systematic Review and Meta‐Analysis of Randomized Controlled Trials

Introduction Neurocritical care patients, including those with traumatic brain injury, subarachnoid hemorrhage, and intracerebral hemorrhage, often develop anemia, compromising brain oxygen delivery and increasing morbidity and mortality. Blood transfusion strategies, either liberal or restrictive, are commonly used to manage anemia in these patients, but the optimal approach remains unclear due to mixed results in existing studies. Methods A systematic search of PubMed, Cochrane Library, ScienceDirect, and Google Scholar from inception to December 2024 for randomized controlled trials (RCTs) evaluating restrictive versus liberal transfusion strategies in adult neurocritical care patients. Outcomes included mortality, Glasgow Outcome Scale (GOS), red blood cell (RBC) units transfused, sepsis, intensive care unit (ICU)/hospital length of stay, and secondary complications. The study is registered with PROSPERO (CRD42025635426). Findings The analysis included seven RCTs with 1941 patients. The restrictive strategy significantly reduced the number of RBC units transfused per patient (MD: 2.36; 95% CI: 1.08–3.64; p = 0.0003) and was associated with a lower incidence of sepsis (RR: 0.73; 95% CI: 0.56–0.96; p = 0.02). There were no significant differences between restrictive and liberal strategies for ICU (RR 0.74; 95% CI 0.28–1.91; p = 0.53), in‐hospital (RR 0.77; 95% CI 0.35–1.68), 30‐day (RR 0.91; 95% CI 0.70–1.18), 6‐month (RR 0.98; 95% CI 0.67–1.44), or long‐term mortality (RR 1.00; 95% CI 0.80–1.24). GOS scores at 6 months showed no significant difference (RR 0.94; 95% CI 0.83–1.07). ICU and hospital length of stay were also comparable between strategies. Secondary outcomes, including stroke, brain hypoxia, intracranial hypertension, and other non‐neurological complications, showed no significant differences between the two strategies. Conclusion Restrictive transfusion strategies are as effective as liberal strategies in terms of mortality and neurological complications, with additional benefits such as fewer RBC transfusions and lower sepsis rates. These findings support restrictive strategies as a safer approach to managing anemia in neurocritical care, though further research on long‐term outcomes is needed.