Is HBOT treatment effective in recovering zone of stasis? An experimental immunohistochemical study.

Studies aimed at recovering the zone of stasis are one of the major issues of experimental burn studies. Hypoxia and oedema at that zone may cause irreversible changes. Due to anti-oedematous and antihypoxic effects of hyperbaric oxygen treatment (HBOT), it may be beneficial in recovering the zone of stasis. We performed an experimental study using 20 Sprague-Dawley rats, each weighing 350-450 g. The rats were first divided into two groups as 24h and 5 days. Subsequently, control and treatment groups (five rats in each group) were formed. For burn wounds, we used the burn comb model, which was described by Regas and Ehrlich. In the treatment group, 2.5 ATA HBOT was applied for 90 min twice daily. A 0.8-cm punch biopsy was performed and samples for histological examination were taken from the centre of burn area. The rats were sacrificed by administering '3 mci technetium-99m methoxy butyl nitrite' ((99)Tc(m) MIBI) through the femoral vein. Biopsy materials were evaluated by histological and immunohistochemical methods. Dorsal skin fragment, excised to 1cm margin, was imaged by scintigraphic measurements with a gamma camera. Wet and dry weight measurements of excised skin fragments were taken. As a result, HBOT showed a positive effect at the cellular level in the first 24h. It increased recovery potential by augmenting neovascularisation and decreasing oedema in the 5-day group.