Patients who experience lung injury are often placed on a ventilator to help them heal; however, if the ventilator volume settings are too high, it can cause additional lung injury. It is proven that using lower ventilator volume settings improves outcomes. In patients with acute brain injury, it is proven that maintaining a normal partial pressure of carbon dioxide in the arterial blood improves outcomes. Mechanical ventilator settings with higher volumes and higher breathing rates are sometimes required to maintain a normal partial pressure of carbon dioxide. These 2 goals of mechanical ventilation, using lower volumes to prevent additional lung injury but maintaining a normal partial pressure of carbon dioxide, are both important for patients with acute brain injury. The investigators have designed a computerized ventilator protocol in iCentra that matches the current standard of care for mechanical ventilation of patients with acute brain injury by targeting a normal partial pressure of carbon dioxide with the lowest ventilator volume required.