Hyperbaric oxygen (HBO2 ) therapy in thermal burn injury revisited. Pressure does matter. Review

For over five decades, many experimental and clinical studies have shown predominantly positive but controversial results on the efficacy of hyperbaric oxygen (HBO2) therapy in burns. The study aimed to define a common denominator or constellations, respectively, linked to the effects of HBO2 in burns with a special focus on dosage parameters. Based on original work since 1965, species, number of individuals, type of study, percentage of total body surface area (TBSA), region, depth of burn, causative agent, interval between burn and first HBO2 session, pressure, duration of individual session, number of HBO2 sessions per day, cumulative number of HBO2 sessions and type of chamber were assessed. Out of 47 publications included, 32 were animal trials, four were trials in human volunteers, and 11 were clinical studies. They contained 94 experiments whose features were processed for statistical evaluation. 64 (67.4%) showed a positive outcome, 16 (17.9%) an ambiguous one, and 14 (14.7%) a negative outcome. The only factor independently influencing the results was pressure with ATA (atmospheres absolute) lower than 3 ATA being significantly associated with better outcomes (p=0.0005). There is a dire need for well-designed clinical studies in burn centers equipped with hyperbaric facilities to establish dedicated treatment protocols.