Hyperbaric side effects in a traumatic brain injury randomized clinical trial.

OBJECTIVE: To catalog the side effects of 2.4 atmospheres absolute (atm abs) hyperbaric oxygen (HBO2) vs. sham on post-concussion symptoms in military service members with combat-related, mild traumatic brain injury (TBI). METHODS: Fifty subjects diagnosed with TBI were randomized to either a sham (1.3 atm abs breathing air) or treatment (2.4 atm abs breathing 100% oxygen) hyperbaric profile. Forty-eight subjects completed 30 exposures. Medical events during hyperbaric exposures were separately annotated by medical staff and chamber operators. After the blind was broken, events were segregated into the exposure groups. RESULTS: These side effects were observed as rate (sham/treatment): ear block (ear barotrauma) 5.51% (1.09%/5.91%), sinus squeeze 0.14% (0.0%/0.27%), and confinement anxiety 0.27% (0.27%/0.27%). Other conditions that occurred included: headache 0.61% (0.68%/0.54%); nausea 0.2% (0.14%/0.27%); numbness 0.07% (0%/0.13%); heartburn 0.07% (0.14%/0%); musculoskeletal chest pain 0.07% (0%/0.13%); latex allergy 0.07% (0.14%/0%); and hypertension 0.07% (0.14%/0%). CONCLUSION: This study demonstrated no major adverse events, such as pulmonary barotraumas, pulmonary edema or seizure. Given the infrequent, mild side effect profile, the authors feel the study demonstrated that hyperbaric oxygen therapy (HBO2T) was safe at a relatively high treatment pressure in TBI subjects, and these data can be used to evaluate the risk/ benefit calculation when deciding to utilize HBO2T for treatment of various diseases in the TBI population.