Transfusion Guidelines in Brain Tumor Surgery: A Systematic Review and Critical Summary of Currently Available Evidence

Objective: Red blood cell (RBC) transfusion is commonly indicated in brain tumor surgery due to risk of blood loss. Current transfusion guidelines are based on evidence derived from critically ill patients and may not be optimal for brain tumor surgeries. Our study is the first to synthesize available evidence to suggest RBC transfusion thresholds in brain tumor patients undergoing surgery. Methods: A systematic review was conducted using PubMed, EMBASE, and Google Scholar databases in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines to critically assess RBC transfusion thresholds in adult patients with brain tumors and complications secondary to transfusion following blood loss in the operating room or perioperative period. Results: Seven articles meeting our search criteria were reviewed. Brain tumor patients who received blood transfusions were older, had greater rates of American Society of Anesthesiologists class 3 or 4, and presented with increased number of comorbidities including diabetes, hypertension, and cardiovascular diseases. In addition, transfused patients had a prolonged surgical time. Transfusions were associated with multiple postoperative major and minor complications, including longer hospital length of stay, increased return to the operating room, and elevated 30-day mortality. Analysis of transfusion thresholds showed that a restrictive hemoglobin threshold of 8 g/dL is safe in patients, as evidenced by a reduction in length of stay, mortality, and complications (level C class IIa). Conclusions: A restrictive Hb threshold of 8 g/dL appears to be safe and minimizes potential complications of transfusion in brain tumor patients.