Inclusion Criteria:  Arrival to the hospital within 6 hours of injury Age >= 18 years old Patients with traumatic brain injury(TBI). TBI is defined as any alteration or loss of consciousness with or without positive head C.T findings.  Exclusion Criteria:  Deemed to have a non-survivable TBI Brain dead on arrival Active substance abuse for opiates and cocaine as noted by admission toxicology screen. Any thoracic or abdominal injury resulting in open surgical intervention Pregnancy Prisoners Active military Non - English speaking (due to necessity for consent in aims 2 and 3) Age > 89 years