title: [Influence of temperature on extracellular glucose and lactate after traumatic brain injury].
abstract: OBJECTIVE
  To study the changes of extracellular glucose (Glu), lactate (Lac), and the ratio of lactate/pyruvate (L/P) in patients with traumatic brain injury under different body temperatures.
  
  
  METHODS
  Catheters for microdialysis were punctured into the penumbra zone of injured brain tissue (INJ), relatively normal brain tissue (NOR), and abdominal subcutaneous tissue (ABD) respectively in 51 patients to collect the fluid. The perfusion rate was 0.3 microl/min and one tube of fluid was collected for each hour. The average collection time was (67.10 +/- 18.27) hours. Concentrations of Glu, Lac, and pyruvate (Pyru) in the fluid were analyzed using CMA microdialysis analyzer. Patients were divided into 7 groups according to their rectal temperature (RT) values, which were RT < 33.0 degrees C, 33.0-33.9 degrees C, 34.0-34.9 degrees C, 35.0-35.9 degrees C, 36.0-36.9 degrees C, 37.0-37.9 degrees C, and > or = 38.0 degrees C.
  
  
  RESULTS
  The concentration of Glu in ABD was significantly higher than that in the brain tissue (P < 0.05). The Glu in NOR were significantly higher and the highest in 33.0 degrees C compared with that in the INJ when RT < 36.0 degrees C (P < 0.05). The concentration of Lac in ABD was significantly lower than that in brain (P < 0.05). The Lac in NOR were much higher than that in INJ when RT < 35.0 degrees C or > or = 37.0 degrees C (P < 0.05). The ratio of L/P decreased along with the increase of body temperature (P < 0.001). The ratio of L/P significantly decreased in an order of INJ > ABD > NOR when RT was lower than 33.0 degrees C, which was changed to the order of NOR > INJ > ABD when RT was higher than 34.0 degrees C.
  
  
  CONCLUSIONS
  Treatment of hypothermia may play more protective role when RT were between 33-34 degrees C or 36-37 degrees C.
authors.affiliation: Department of Neurosurgery, Tianjin Neurological Central Hospital, Tianjin 300060, China. tnhnice@public.tpt.tj.cn
authors.forename: Da-shi
authors.initials: DS
authors.lastname: Zhi
authors.forename: Hui-ling
authors.initials: HL
authors.lastname: Huang
authors.forename: Guo-bin
authors.initials: GB
authors.lastname: Zhang
authors.forename: Ai-lin
authors.initials: AL
authors.lastname: Li
authors.forename: Wei-jia
authors.initials: WJ
authors.lastname: Fan
authors.forename: Chen
authors.initials: C
authors.lastname: Wang
authors.forename: Li-dong
authors.initials: LD
authors.lastname: Mo
mesh_terms: D000328:Adult; D001831:Body Temperature; D001930:Brain Injuries / Q000503:physiopathology* / Q000628:therapy; D005110:Extracellular Space / Q000378:metabolism*; D005260:Female; D005947:Glucose / Q000378:metabolism*; D006801:Humans; D019344:Lactic Acid / Q000378:metabolism*; D008297:Male; D017551:Microdialysis; D008875:Middle Aged
chemical_list: D019344:Lactic Acid; D005947:Glucose