HYPERBARIC-OXYGEN IMPROVES WOUND-HEALING IN NORMAL AND ISCHEMIC SKIN TISSUE

The influence of hyperbaric oxygen on reepithelialization and on micro vascular perfusion of wounds in normal and ischemic skin tissue was in vestigated by using a standardized model, in ears of hairless mice. An imals were treated within 2 hours of wound creation and then twice dai ly with 100% oxygen at 2 atmospheres of absolute pressure. Ischemia wa s induced by Ligating two of the three major vessels of the ear 2.5 da ys before wound creation. Wound surface area was measured every third day after wound creation. In addition, microvascular blood flow before and during the wound healing process was measured by scanning the ear with a new laser Doppler perfusion imager. In normal tissue (n = 13), hyperbaric oxygen therapy significantly accelerated wound healing by 2 days (p<0.01) as compared with controls (n = 16). In ischemic tissue (n = 16), treatment with hyperbaric oxygen reduced time for reepithel ialization in control animals (n = 16) from 14.3 to 9.9 days (p<0.001) . Laser Doppler data showed no difference in tissue blood flow between treated and untreated animals. In comparison with normal tissue, woun d healing in ischemic tissue was characterized by a reduced and less i ntense hyperemic response. These data suggest that hyperbaric oxygen t herapy improves reepithelialization in normal and ischemic skin tissue . The beneficial effect is not associated with changes in microvascula r perfusion and therefore is probably due to high arteriolar oxygen co ntent and oxygen diffusion.