ABSTRACT
 Complications associated with diabetes are often expensive to treat, and commonly include foot ulceration. While most diabetic foot ulcers heal with standard treatment, when standard treatment measures fail, adjunctive therapies must be considered. We review the theory and evidence for the use of systemic Hyperbaric Oxygen Therapy (HBOT) as an adjunctive treatment for chronic lower extremity diabetic ulceration. Two clinical cases of patients treated with HBOT for refractory diabetic foot ulceration at Georgetown University Hospital are presented. A growing body of evidence suggests that oxygen plays a major role in whether wounds heal normally or remain nonhealing chronic wounds. An oxygen gradient, from high oxygen levels in the edges of the wound to hypoxic conditions in the wound center, seems to optimally stimulate wound healing. Wounds that are instead surrounded by hypoxic tissue lack this oxygen gradient and seem less likely to heal. In wounds with adequate perfusion, HBOT may overcome periwound hypoxia to create an oxygen gradient and stimulate healing of otherwise nonhealing wounds. The clinical trials assessing the effectiveness of HBOT in diabetic wound healing have been inconclusive. However, considering the evidence supporting oxygen's role in wound healing and the potential for HBOT to decrease medical costs related to the care of chronic diabetic ulcers, there is a need for more extensive clinical trials to evaluate HBOT efficacy.