OBJECTIVETo study the effect of mild hypothermia on glucose metabolism and glycerol of brain tissue in patients with severe traumatic brain injury (STBI) using clinical microdialysis.

METHODSThirty-one patients with STBI(GCS less than or equal to 8) were randomly divided into hypothermic group(Group A) and control group(Group B). Microdialysis catheters were inserted into the cerebral cortex of perilesional and normal brain tissue. All samples were analyzed using CMA microdialysis analyzer.

RESULTSIn comparison with the control group, lactate/glucose ratio(L/G), lactate/pyruvate ratio(L/P) and glycerol(Gly) in perilensional tissue were significantly decreased; L/P in normal brain tissue was significantly decreased. In control group, L/G, L/P and Gly in perilensional tissue were higher than that in normal brain tissue. In the hypothermic group, L/P in perilensional tissue was higher than that in relative normal brain.

CONCLUSIONSMild hypothermia protects brain tissues by decreasing L/G, L/P and Gly in perilensional tissue and L/P in "normal brain" tissues. The energy crisis and membrane phospholipid degradation in perilensional tissue are easier to happen after traumatic brain injury, and mild hypothermia protects brain better in perilensional tissue than in normal brain tissue.