title: Hyperbaric oxygen for blast-related postconcussion syndrome: three-month outcomes.
abstract: OBJECTIVE
  Mild traumatic brain injury (mTBI) and postconcussion syndrome (PCS) are common among military combatants. Hyperbaric oxygen (HBO2 ) is a proposed treatment for these conditions, but it has not been rigorously studied. The objective of this study was to determine the effects of HBO2 by 3 months post compression at 2 commonly employed dosing levels to treat PCS; whether specific subgroups may have benefited; and if no overall effect was found, whether benefit is masked by other conditions.
  
  
  METHODS
  This randomized, double-blind, sham-controlled study was conducted at the Naval Air Station in Pensacola, Florida on 61 male Marines with a history of mTBI and PCS. Intervention consisted of 40 once daily 60-minute hyperbaric chamber compressions at 2.0 atmospheres absolute (ATA) at 1 of 3 randomly preassigned oxygen fractions, resulting in respective blinded groups with an oxygen-breathing exposure equivalent to (1) surface air (sham), (2) 100% oxygen at 1.5ATA, or (3) 100% oxygen at 2.0ATA. The main outcome measure was the Rivermead Post-Concussion Questionnaire-16 (RPQ-16) collected before compressions and at 2 later points.
  
  
  RESULTS
  The interaction of time by intervention group was not significant for improvement on the RPQ-16. Nor was there evidence of efficacy on the RPQ-16 for any subgroup. No significant time by intervention interaction was found for any functional, cognitive, or psychomotor secondary outcome measure at an unadjusted 0.05 significance level.
  
  
  CONCLUSIONS
  Using a randomized control trial design and analysis including a sham, results showed no evidence of efficacy by 3 months post-compression to treat the symptomatic, cognitive, or behavioral sequelae of PCS after combat-related mTBI.
authors.affiliation: Physical Medicine and Rehabilitation Program Office, Department of Veterans Affairs, Washington, DC; Department of Physical Medicine and Rehabilitation, Virginia Commonwealth University, Richmond, VA; Hunter Holmes McGuire Veterans Affairs Medical Center, Richmond, VA; Center for Rehabilitation Sciences and Engineering, Richmond, VA.
authors.forename: David X
authors.initials: DX
authors.lastname: Cifu
authors.forename: William C
authors.initials: WC
authors.lastname: Walker
authors.forename: Steven L
authors.initials: SL
authors.lastname: West
authors.forename: Brett B
authors.initials: BB
authors.lastname: Hart
authors.forename: Laura Manning
authors.initials: LM
authors.lastname: Franke
authors.forename: Adam
authors.initials: A
authors.lastname: Sima
authors.forename: Carolyn W
authors.initials: CW
authors.lastname: Graham
authors.forename: William
authors.initials: W
authors.lastname: Carne
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001930:Brain Injuries / Q000628:therapy*; D004311:Double-Blind Method; D005500:Follow-Up Studies; D006801:Humans; D006931:Hyperbaric Oxygenation / Q000379:methods*; D008297:Male; D009483:Neuropsychological Tests; D038223:Post-Concussion Syndrome / Q000628:therapy*; D015599:Trauma Severity Indices; D016896:Treatment Outcome; D055815:Young Adult