Fig. 2From: Preoperative hemoglobin and perioperative blood transfusion in major head and neck surgery: a systematic review and meta-analysisMeta-analysis of preoperative Hgb (g/dL) and subgroup analysis for patients who did not have a perioperative blood transfusion (PBT) and those who did. Hgb, hemoglobin in grams per decaliter; PBT, perioperative blood transfusionBack to article page