The mechanical ventilation strategy has changed over years worldwide. Several international researches have been conducted to study the association of the use of mechanical ventilation with clinical outcomes. In this prospective, multicenter, cross-sectional survey, the practice of mechanical ventilation among patients with severe brain injury will be investigated in 70 intensive care units in China.

Inclusion Criteria:

1. older than 18 years
2. with severe brain injury (including severe traumatic brain injury, ischemic stroke, subarachnoid hemorrhage, spontaneous intracerebral hemorrhage, hypoxic-ischemic encephalopathy, intracranial tumor, intracranial infection and idiopathic epilepsy)
3. mechanical ventilated for at least 24 hours before the time of on-spot survey

Exclusion Criteria:

1. undergoing a spontaneous breathing trial (SBT) at the time of on-spot survey
2. underwent at least once SBT in the preceding 24 hours before time of on-spot survey
3. enrolled in another trial

Mechanical ventilated patients with severe brain injury