Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học quốc tế cung cấp cho các bạn kiến thức về ngành y đề tài: Brain metabolism is significantly impaired at blood glucose below 6 mM and brain glucose below 1 mM in patients with severe traumatic brain injury. | Meierhans et al. Critical Care 2010 14 R13 http content 14 1 R13 c CRITICAL CARE RESEARCH Open Access Brain metabolism is significantly impaired at blood glucose below 6 mM and brain glucose below 1 mM in patients with severe traumatic brain injury Roman Meierhans21 Markus Béchirt1 Silke Ludwig 1 Jutta Sommerfeld1 Giovanna Brandi1 2 Christoph Haberthur3 Reto Stocker1 and John F Stover 1 Abstract Introduction The optimal blood glucose target following severe traumatic brain injury TBI must be defined. Cerebral microdialysis was used to investigate the influence of arterial blood and brain glucose on cerebral glucose lactate pyruvate glutamate and calculated indices of downstream metabolism. Methods In twenty TBI patients microdialysis catheters inserted in the edematous frontal lobe were dialyzed at 1 pl min collecting samples at 60 minute intervals. Occult metabolic alterations were determined by calculating the lactate- pyruvate L P lactate- glucose L Glc and lactate- glutamate L Glu ratios. Results Brain glucose was influenced by arterial blood glucose. Elevated L P and L Glc were significantly reduced at brain glucose above 1 mM reaching lowest values at blood and brain glucose levels between 6-9 mM P . Lowest cerebral glutamate was measured at brain glucose 3-5 mM with a significant increase at brain glucose below 3 mM and above 6 mM. While L Glu was significantly increased at low brain glucose levels it was significantly decreased at brain glucose above 5 mM P . Insulin administration increased brain glutamate at low brain glucose but prevented increase in L Glu. Conclusions Arterial blood glucose levels appear to be optimal at 6-9 mM. While low brain glucose levels below 1 mM are detrimental elevated brain glucose are to be targeted despite increased brain glutamate at brain glucose 5 mM. Pathogenity of elevated glutamate appears to be relativized by L Glu and suggests to exclude insulin- induced brain injury. Introduction .
