Hyperoxygenated solution improves tissue viability in an avulsion injury flap model

Abstract

Management of avulsion injuries remains a challenge due to necrosis. The aim of the present study is to create an experimental model reproducing an avulsion injury and investigate the effects of hyperoxygenated solution (HOS), a method of oxygen delivery that has been widely used in the therapy of ischaemia-hypoxia diseases, on avulsion injury flap survival in rats. Forty male rats were divided into four groups (n = 10 each). Dorsal random pattern flaps measuring 3 × 9 cm, including the panniculus carnosus, were elevated and run over by the skin avulsion model machine, and the flaps were then sutured into their original places. The sham+HOS and avulsion+HOS groups received intravenous HOS (20 ml/kg) each day for 7 days after the operation. The sham+saline and avulsion+saline groups received intravenous saline solution (20 ml/kg) each day for 7 days after the operation. Percutaneous O2 pressure (TcpO2) measurement, serial examinations of skin flap blood perfusion, skin flap survival evaluation and histopathology were performed to assess the efficacy of HOS on avulsion injury. Compared to the avulsion+saline groups, TcpO2 was significantly higher in the avulsion+HOS groups at 15, 30 and 60 min after infusion (P<0.05). The blood perfusion of flaps in the avulsion+HOS group was higher than in the avulsion+saline group (P<0.05). The survival rate was higher in the avulsion+HOS group than in the avulsion+saline group (P<0.05), and the histopathology assays supported the data. We succeeded in developing an avulsion injury model and demonstrated that HOS could improve the survival of the avulsion injury flaps in rats by effectively increasing the local oxygen content and blood perfusion and ameliorating inflammatory damage.