Hyperbaric Oxygen and Diabetic Foot
During Hyperbaric Oxygen Therapy, a person breathes 100% Oxygen at a pressure higher than atmospheric pressure. In tissues, normally, the partial pressure of Oxygen ranges from 50-80 mmHg. Delivery of 100% Oxygen raises this number to 400-500 mmHg. Inhalation of 100% Oxygen in a Hyperbaric Chamber at a pressure of 2.2 Atmospheres raises the available Oxygen to 1672 mmHg, of which 1000-1500 mmHg partial Oxygen pressure is available in the tissues. Although the available final amount of Oxygen may be significantly lower than that for vascular reasons, it remains quite high compared to that of normal respiration.
Macrophages and fibroblasts need some Oxygen pressures above 30 mmHg to function effectively and this is not achieved in hypoxic-diabetic ulcers. The required production of growth factors by cells is successful either at very low oxygen levels or at very high levels - what only hyperbaric oxygen can provide. Low oxygen levels carry the risk of cell death. On the other hand, collagen synthesis depends on oxygen adequacy. It has been shown that a partial pressure of oxygen of 250 mmHg leads to maximum collagen production. This "amount" of Oxygen is well above normal and can only be achieved with Hyperbaric Oxygen Therapy.
Hyperbaric Oxygen Therapy
The hyperoxia achieved during Hyperbaric Oxygen Therapy has many positive effects on the "diabetic foot" that lead to a successful outcome and in most cases healing, as well as:
- Causes vasoconstriction by reducing swelling
- Increases the "lethal" ability of leukocytes against microorganisms
- Increases collagen production through fibroblasts and promotes neo-angiogenesis (creation of new small vessels), creating conditions for efficient microcirculation in both the diseased and the "healthy" (without obvious ulcer - wound) foot
- It has microbicidal and microbiostatic action, while it shows synergy with some antibiotics