Hyperbaric oxygen therapy involves exposing the body to 100 percent oxygen at a pressure that is greater than what you normally experience. Wounds need oxygen to heal properly, and exposing a wound to 100 percent oxygen can, in many cases, speed the healing process.
Hyperbaric oxygen – its mechanisms and efficacy
This paper outlines therapeutic mechanisms of hyperbaric oxygen therapy (HBO2) and reviews data on its efficacy for clinical problems seen by plastic and reconstructive surgeons.
It used to be associated with treating "the bends," but breathing pure oxygen can promote healing in other ways as well.