- Simple physical interventions to implement early:
  - Head of bed elevated to 30-45 degrees or reverse Trendelenburg (if in spinal precautions)
  - Keep head straight to avoid kinking of the internal jugular veins (to promote venous drainage)
  - Avoid tight cervical collars and tight circumferential endotracheal tube/tracheostomy tube ties
- Imaging: Patients with a suspected traumatic brain injury with altered mental status (GCS 12 or less) should have a non-contrast head CT as soon as possible. For penetrating head injuries, in addition to the non-contrast head CT study, a CT angiogram of the brain should also be obtained to evaluate for vascular injuries (e.g., pseudoaneurysms).
- Blood products are the preferred resuscitative fluid for hypotension in all trauma patients. Avoid Albumin and hydroxyethyl starches; albumin is associated with worse outcomes when used in TBI patients.19,20
- Tranexamic acid: All patients with evidence of moderate or severe TBI should be administered 2gm of TXA within 3hrs of injury; 2gm of TXA in TBI patients improves survival.21,
- If severe TBI is suspected, antiepileptics (Keppra, 1500 mg loading dose) should be administered during the initial evaluation and within 30 minutes of arrival.
- For casualties with abnormal GCS who do not require resuscitation for hypotension or major blood loss, use normal saline or 3% hypertonic saline for volume resuscitation. Both have shown equivalent outcomes in severe TBI. Avoid hypotonic fluids (e.g., any IVF with Dextrose % in water [D5W]).
- For casualties with GCS ≤ 8, manage hypotension by maintaining systolic blood pressure greater than 110 mmHg.22 A systolic blood pressure of less than 90mmHg is the single risk factor most highly associated with mortality in brain trauma.23,24
- End tidal CO2 (EtCO2) should be monitored during prehospital care and continued after handoff to a surgical team. Normoventilation with a goal partial pressure of carbon dioxide (PaCO2) of 35-45mmHg should be maintained or EtCO2 of 35-45 mmHg. DO NOT hyperventilate.
- Prophylactic hyperventilation is not recommended as it decreases cerebral blood flow. It may be used as a temporizing measure to reduce intracranial pressure in the setting of suspected herniation until other therapies are employed to decrease intracranial pressure as the patient is on the way to the operating room.25 Hyperventilation can be harmful. 22
- For penetrating brain injuries and open skull fractures, routine prophylactic antibiotics are indicated.26 Antibiotic recommendations for the first level of surgical care include either cefazolin 2gm IV every 6-8 hours or clindamycin 600mg IV every 8 hours. If a penetrating head injury appears grossly contaminated with organic debris, consider addition of metronidazole 500mg IV every 8-12 hours.26
- For isolated closed head injuries, routine prophylactic antibiotics are not indicated.
- Hypoglycemia and hyperglycemia must be avoided. Monitor glucose every 6 hours. The goal is to maintain glucose < 180 mg/dl and avoid hypoglycemia.27 D5W IVF will worsen cerebral edema. Do NOT use intravenously to maintain euglycemia.
- Steroids should be avoided in brain-injured patients as they have not shown outcome benefit and increase mortality in patients with severe brain injury.25,28
- A common strategy for management of hypoxemia has been a goal of arterial oxygen saturation (SaO2) >90% and the partial pressure of oxygen in the arterial blood (PaO2) >60 mmHg.24 However, in order to establish a safety buffer in the deployed setting often characterized by frequent patient handoffs and occasional equipment challenges, a goal SaO2 of 93% and PaO2 >80mmHg, is recommended. Particular attention to avoidance of hypoxemia during air transport is essential as human studies and animal models indicate hypoxia during aeromedical evacuation is common.29,30
- Document serial neurological exam findings every hour, including:
  - Glasgow Coma Score broken down by eyes, voice, motor scores. (See Table 1.)
  - Presence of gross focal neurologic signs and/or deficit.
  - Pupil size and reactivity. See below Figures 1 and 2.
  - When available, quantitative pupillometry should be assessed and documented to ensure accuracy and consistency of recordings.31-33 Quantitative pupillometry and the neurologic pupillary index (NPi) allows objective and consistent assessment of pupillary reactivity to track trends and determine if a patient’s responsiveness is worsening. ICU nurses should be documenting these findings and they should be trended.
  - NPi < 3.0 is concerning for an abnormal or sluggish pupil and therefore increased intracranial pressure. NPi should be documented and significant changes indicate the need to assess or empirically treat for increased intracranial pressure. If a neurosurgeon is not managing the patient; telehealth support to review NPi should be considered. (See Appendix D.)