ICP Threshold After Decompressive Craniectomy

Inclusion Criteria: * history of traumatic brain injury age: 18-80 years admission GCS score≤8 admitting to hospital with 24 hours after injury received decompressive craniectomy received invasive ICP monitoring Exclusion Criteria: * refuse follow-up received operation before admitting to hospital received cardio-pulmonary resuscitation after injury disturbance of consciousness caused by non-traumatic reasons prior history of traumatic brain injury or stroke expected lifetime less than 180 days admitting to other ongoing study systemic disease: uremia, liver cirrhosis, malignant tumor, mental disease, drug or alcohol dependence