Pyoderma gangrenosum: skin grafting after preparation with hyperbaric oxygen.

Four patients with pyoderma gangrenosum were treated with hyperbaric oxygen to prepare the wounds for skin grafting. Each wound responded to a course of daily hyperbaric oxygen with reduction of infection and increased capillary angiogenesis. During follow-up periods of 12 to 30 months, all wounds remained healed. Although the exact etiology of pyoderma gangrenosum is unknown, vasculitis with wound ischemia and infection are prominent components. Inspired oxygen partial pressures of 1100 to 1300 mmHg elevate wound oxygen tension despite relative ischemia. The impaired intracellular bacterial killing of hypoxic leukocytes is corrected during each day's 2-hour bolus of hyperbaric oxygen. Daily wound oxygenation increases collagen production by fibroblasts to support capillary angiogenesis.