亚低温治疗对重型脑创伤脑组织糖代谢及甘油的影响

Effect of mild hypothermia on glucose metabolism and glycerol of brain tissue in patients with severe traumatic brain injury

目的研究亚低温对重型脑创伤患者脑组织糖代谢及甘油的影响。方法33例患者随机分为亚低温组和常温组,将微透析探针分别置入病损周边区、病灶对侧的相应位置及腹部皮下脂肪组织,分析亚低温组及常温组脑细胞间液(extracellular fluid,ECF)的乳酸/丙酮酸(lactate/pyruvate,L/P)、乳酸/葡萄糖(lactate/glucose,L/G)及甘油(glycerol,Gly)浓度。结果亚低温组比常温组“正常区”脑ECF的L/P有明显降低;亚低温组比常温组病损周边区甘油、L/G及L/P有明显降低;常温组病损周边区比“正常区”的甘油、L/G及L/P明显增高;亚低温组病损周边区L/P比“正常区”有明显增高。结论亚低温治疗可能通过降低病损周边区脑ECF中L/P、L/G及甘油的浓度及“正常区”L/P的浓度而发挥脑保护作用;颅脑创伤后病损周边区更易发生能量代谢紊乱及细胞膜降解,亚低温对这一区域有显著保护作用。

Objective To study the effect of mild hypothermia on glucose metabolism and glycerol of brain tissue in patients with severe traumatic brain injury (sTBI). Methods All 33 patients with sTBI (GCS≤8) were randomly divided into hypothermic group and control group. Microdialysis catheters were inserted into the cerebral cortex of perilesion, relative normal brain tissue and subcutaneous tissue of abdomen in order to analyze the concentrations of lactate/pyruvate (L/P), lactate/glucose (L/G)and the glycerol (Gly) in extracellular fluid (ECF). Results In comparison with the control group, the concentration of L/G, L/P and Gly in periphery and that of L/P in ECF of the “normal brain tissue” were significantly decreased in the hypothermic group. In control group, concentrations of L/G, L/P and Gly in periphery were higher than those in relative normal brain. In the hypothermic group, L/P concentration in periphery was higher than that in relative normal brain. Conclusions Mild hypothermia protects brain by decreasing concentrations of L/G,L/P and Gly in periphery and L/P concentration in “normal brain tissue”. The energy crisis and membrane phospholipid breakage in periphery are easier to happen after TBI, where mild hypothermia exerts significant protective role.