Hypoxia in the relatively ischemic diabetic foot impairs leukocyte bacterial killing and fibroblast-collagen support for capillary angiogenesis. Infection in even the relatively young, "warm-foot" diabetic with microangiopathy, neuropathy, and infection leads to hypoxia due to local high oxygen consumption. The 1100 to 1300 mm Hg arterial PO2 achievable with hyperbaric oxygen results in elevation of wound PO2. Periodic correction of wound hypoxia improves leukocyte bacterial killing and support for capillary angiogenesis. Hyperbaric oxygen is usually futile in the elderly diabetic with significant and generalized large-vessel occlusion.

Davis, , , , , , , , (1987). The use of adjuvant hyperbaric oxygen in treatment of the diabetic foot. Clinics in podiatric medicine and surgery, 1987 Apr;4(2):429-37. https://www.ncbi.nlm.nih.gov/pubmed/2952252