Changes in regional cerebral oxygen saturation and lactic acid in cerebrospinal fluid after hypothermia treatment in patients with severe brain injury

Objective:To investigate the effect of mild hypothermiatreatment on the regional cerebral oxygen saturation (rScO 2),intracranial pressure(ICP) and lactic acid (LA) of cerebrospinal fluid (CSF) in patients with severe brain injury(SBI).Methods:Fortynine patients with severe brain injury〔Glasgow coma scale(GCS)≤8 scores〕 were randomly divided into the hypothermic ( n= 25) and the control ( n= 24) groups.Hypothermia was induced 20 hours after the injury,and rewarming was begun on 25 days 〔mean(65 43±17 39)hours〕 after the rectal temperature reached 32 5 ℃34 5 ℃.Meanwhile,the vital signs,blood electrolytes,ICP,cerebral perfusion pressure(CPP),jugular venous oxygen saturation(SjO 2),arterial oxygen saturation (SaO 2),rScO 2 and LA in CSF were measured.The prognosis of the patients was evaluated according to Glasgow outcome scale(GOS).Results:In comparison with the control group,the high ICP and LA in CSF significantly declined ( P 0 05 or P 0 01),while the low CPP and rScO 2 were markedly elevated in hypothermic group ( P 0 01 or P 0 05).However,there was no marked change in the vital signs,SjO 2,and SaO 2.The mortality was decreased and the prognosis of the patients improved in the hypothermic group.Conclusions:Mild hypothermia is a safe and effective therapy to prevent secondary brain damage in the patients with severe brain injury,and it can reduce the mortality and improve the prognosis.Monitoring the rScO 2 is an important procedure in hypothermic therapy.