This study is a prospective multi-centre randomized trial to compare the effect of long-term mild hypothermia versus routine normothermic intensive management in patients with severe traumatic brain injury. The primary hypothesis is that the induction of mild hypothermia (maintained at 34-35℃) for 5 days will improve the outcome of patients at six months post injury compared with normothermia.
Inclusion Criteria: * Age 18 - 65 years within 6 hours post injury; * Closed head injury; * Glasgow Coma Scale(GCS) score 4 to 8 after resuscitation; * The intracranial pressure is more than 25 mmHg; * Cerebral contusion on computed tomographic scan. Exclusion Criteria: * GCS of 3 with bilateral fixed and dilated pupils; * A life-threatening injury to an organ other than the brain; * No spontaneous breathing or cardiac arrest at the scene of the injury; * No consent; * Pregnancy.