The goal of this research is to serve as a demonstration project to determine the tolerability of individuals with persistent post-concussive symptoms from combat-related mild TBI (traumatic brain injury), identify dose-finding for HBO2 (Hyperbaric Oxygen) therapy, and determine the efficacy of HBO2 therapy.

Persistent post-concussive symptoms from mild traumatic brain injury are a severe issue facing the readiness, retention and quality of life of Department of Defense(DoD) service members and Veterans. The inadequacy of established treatment regimens and evidence-based science in post-concussive symptoms (PCS)/MTBI is forcing a closer look at non-conventional treatments of this condition. Hyperbaric oxygen (HBO2) is a potent intervention with demonstrated efficacy in dive-related injuries, soft tissue healing, and carbon monoxide poisoning.

This study is prospective, randomized, double-blinded and controlled. A total of 60 subjects will be randomly assigned to one of three treatment arms of the study: 20 subjects into the 1.5 atm abs oxygen equivalent HBO2 treatment, 20 subjects into the 2.0 atm abs oxygen equivalent HBO2 treatment and 20 subjects into the sham treatment (a placebo exposure equivalent to breathing atmospheric air). The protocol utilizes a pre- and post-treatment comprehensive performance battery that will allow for meaningful clinical outcomes and a broad understanding of the effects of the treatment. This project represents a collaboration between the Department of Defense (DoD), the Richmond Veterans Administration Medical Center (VAMC) and Virginia Commonwealth University. Service members will be recruited from military bases/treatment facilities (MTF), receive hyperbaric oxygen at existing DoD hyperbaric chambers and be evaluated by the established Virginia Commonwealth University-Center for Rehabilitation Sciences and Engineering (CERSE), a collaborative research center co-located at the Richmond VAMC and VCU.

Inclusion Criteria:

1. Post-Deployment status after having served in OIF/OEF
2. Blast Event within past 3 years during OIF/OEF deployment [event defined as any of the following symptoms or experiences occurring during or shortly after the blast or explosion: dazed, confused, saw stars, headache, dizziness, irritability, memory gap (not remembering injury or injury period), hearing loss, abdominal pain, shortness of breath, struck by debris, knocked over or down, knocked into or against something, helmet damaged, evacuated]
3. Diagnosis of MTBI within 3 years as confirmed by the TBI specialty team at the Richmond VAMC
4. Presence of post-concussive symptoms from MTBI, confirmed by the VCU-CERSE team at the Richmond VAMC, for at least 3 months
5. Medical clearance to undergo hyperbaric oxygen treatment
6. Stable mental status for at least one month
7. Stable psychotropic medication history for at least one month
8. Ability to perform neuropsychologic testing battery
9. Ability to tolerate neurophysiological and neuroimaging battery

Exclusion Criteria:

1. Traumatic Brain Injury with a primary etiology other than blast
2. Moderate or Severe TBI (moderate or severe brain injury defined as best Glasgow Coma Score in first 24 hours < 12, , brain bleeding or blood clot (i.e., abnormal brain CT scan), or none of first week after event can be remembered.)
3. Past history of moderate or severe TBI
4. Active diagnosis of Post-traumatic Stress Disorder
5. Active diagnosis of Generalized Anxiety Disorder
6. Active Psychosis
7. Past history of Schizophrenia
8. Pre-existing PCS
9. Previous hyperbaric oxygen treatments
10. Contraindications to HBO2, including any "air trapping" pulmonary problems, inability to equalize middle ear and sinuses, or patients who are claustrophobic and require anti-anxiety medication for the condition
11. Active use of cancer medications
12. Pregnancy