Effects of hemoglobin level on the early postsurgical cerebral metabolism in patients with severe traumatic brain injury

Abstract

ABSTRACTObjective: The study aims to explore the effects of different levels of haemoglobin (Hb) on early cerebral metabolism in patients with postoperative severe traumatic brain injury (TBI) .Method: Fifty-nine patients were randomly divided into catheter oxygen group and ventilator-assisted respiratory group. Each group was subsequently divided into three subgroups basing on different Hb level: Hb ≤ 70 g/L subgroup, 71 g/L ≤ Hb≤90 g/L subgroup and Hb ≥ 91 g/L subgroup. The blood samples from the femoral artery and the affected side internal jugular vein were, respectively, taken at the same time from the patient after postoperative 3 days.Results: The incidence of anaemia after severe TBI operation was 88.14%. The VADL and cerebral glucose uptake (CMRglu) in both Hb ≤ 70 g/L and 71 g/L ≤ Hb≤90 g/L patients of oxygen catheter group were less than that in Hb ≥ 91 g/L patients. In the ventilator-assisted breathing group, the VADL and CMRglu of 71 g/L ≤ Hb≤90 g/L patients and Hb ≥ 91 g/L patients were lower than those in Hb ≤ 70 g/L patients. The result from comparing the two 71 g/L ≤ Hb ≤ 90 g/L subgroups showed that the brain metabolic indexs in the ventilator-assisted breathing group were better than those in the catheter oxygen group.Conclusions: In severe TBI postoperative patients, Hb≤90 g/L induced decrease in aerobic oxidation in brain tissue. Moreover, for the same Hb level of 71 g/L ≤ Hb≤90 g/L, ventilator-assisted breathing significantly improved cerebral metabolism.