Mild hypothermia impact on resting energy expenditure in patients with traumatic brain injury: a randomized controlled study

Objective To investigate the changes of metabolic rate in patients with severe traumatic brain injury under hypothermia state, and to assess the effect of hypothermia treatment with the metabolic rate in brain injury patients. Methods Patients with severe brain injury in ICU were enrolled in the study during January 2012 to January 2014. Eighty-three patients were randomly divided into mild hypothermia group (42 cases) and normal group (41 cases). The rectal temperature of mild hypothermia group was controlled in the range of 32 ℃ to 35 ℃ at the first 5 days; while the control group within the normal range (36.5-37.2 ℃). Both groups were measured the resting energy expenditure (REE, kJ/d) with a metabolic cart three times a day. Results The REE of the mild hypothermia group was significantly lower than that of the control group. The REE of the mild hypothermia group was at a low level at the first five days, which was about 60-70% of that of the normal group. The good recovery rate of the treatment group was significant higher than that of the control group [59.52%(25/42) vs. 34.15%(14/41), P 0.05). Conclusions In the range of 32 ℃ to 35 ℃, the REE was greatly reduced (nearly about 60-70% of the normal group), which might change the clinical outcomes in severe brain injury patients. Key words: Craniocerebral trauma; Hypothermia, induced; Energy metabolism; Clinical outcome