Toward treatment of diabetic foot ulcers with hyperbaric water

The O 2 tension (PO 2 ) of skin is the balance between aerobic utilization and O 2 delivery via the microcirculation and direct absorption of atmospheric O 2 across the skin surface. Following injury, skin requires more O 2 to support the energetic requirement of synthesizing new structural elements. In many diabetic patients, microcirculatory function is diminished and cannot increase to sufficiently supply O 2 during wound repair. The present study tests the hypothesis that hyperbaric water can be used to increase skin PO 2 independent of the microcirculation. To test our hypothesis, 20 subjects (25± 0.5yrs) submerged each foot into a container of tap water (CON; 1.7±0.2 mg·L −1 O 2 , PO 2 ≈ 50mmHg, 31.2±0.9C°) or hyperbaric water (HYP; 63.3±0.8 mg·L −1 O 2 , PO 2 ≈ 1010mmHg 33.8±1.4C°) for 30 minutes. TcPO 2 measurements were made on the plantar surface of the big toe before and after treatment. Post‐treatment, skin PO 2 of CON feet decreased from a starting value of 160±0 to 82±5mmHg over 20 minutes. In the HYP group, skin PO 2 increased from 160±0 to 237±9mmHg over 2 minutes and had declined to 117±10mmHg by 20 minutes post‐treatment. Soaking in hyperbaric water was more effective for increasing skin PO 2 than inhaling 100% O 2 for 30 minutes (191±13 and 99±4 at 2 and 15 minutes post‐treatment). These results suggest that soaking the foot in hyperbaric water significantly increases the skin PO 2 and may be useful for treating diabetic foot ulcers.