title: Hyperbaric oxygen therapy for traumatic brain injury: a systematic review of the evidence.
abstract: OBJECTIVE
  To identify the benefits and harms of hyperbaric oxygen therapy (HBOT) to treat traumatic brain injury (TBI).
  
  
  METHODS
  MEDLINE, EMBASE, the Cochrane Library, HealthSTAR, CINAHL, MANTIS, professional society databases, and reference lists. Databases were searched from inception through December 2003.
  
  
  METHODS
  We included English-language studies of patients with TBI given HBOT and evaluating functional health outcomes.
  
  
  METHODS
  Data were abstracted by 1 reviewer and checked by a second. Study quality was rated as good, fair, or poor.
  
  
  RESULTS
  Two fair-quality randomized controlled trials of patients with severe brain injury reported conflicting results. One found no difference in mortality (48% HBOT vs 55% control) or morbidity at 1 year. In young patients with brainstem contusion, significantly more regained consciousness at 1 month with HBOT (67%) than control (11%) (P<.03). The other found a significant decrease in mortality in the HBOT group at 1 year (17%) compared with controls (31%) (P=.037). This decrease in mortality was accompanied by an increase in proportion of patients with severe disability. Patients with intracranial pressure (ICP) greater than 20 mmHg or a Glasgow Coma Scale score of 4 to 6 had significantly lower mortality at 1 year than controls. Five observational studies did not provide better evidence of effectiveness or adverse events. Two indicated a potential for initially reducing elevated ICP in some patients. However, rebound elevations higher than pretreatment levels occurred in some patients. Adverse events, including seizures, pulmonary symptoms, and neurologic deterioration, were reported; however, no study systematically assessed adverse events, and none reported adverse events in control groups.
  
  
  CONCLUSIONS
  The evidence for HBOT for TBI is insufficient to prove effectiveness or ineffectiveness, and more high-quality studies are needed. The evidence indicates that there is a small chance of a mortality benefit, which may depend on subgroup selection. The effect on functional status and the incidence and clinical significance of adverse effects are unclear.
authors.affiliation: Department of Medical Informatics and Clinical Epidemiology, Oregon Evidence-Based Practice Center, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA. mcdonagh@ohsu.edu
authors.forename: Marian
authors.initials: M
authors.lastname: McDonagh
authors.forename: Mark
authors.initials: M
authors.lastname: Helfand
authors.forename: Susan
authors.initials: S
authors.lastname: Carson
authors.forename: Barry S
authors.initials: BS
authors.lastname: Russman
mesh_terms: D001930:Brain Injuries / Q000503:physiopathology / Q000534:rehabilitation*; D002560:Cerebrovascular Circulation; D015600:Glasgow Coma Scale; D006801:Humans; D006931:Hyperbaric Oxygenation; D007427:Intracranial Pressure; D016032:Randomized Controlled Trials as Topic