Hyperoxygenated solution improves tissue viability in an avulsion injury flap model

BACKGROUND

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.

METHODS

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.

RESULTS

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.

CONCLUSION

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.

Hyperoxygenated hydrogen-rich solution suppresses shock- and resuscitation-induced liver injury

BACKGROUND

It is not known whether simultaneous delivery of hydrogen and oxygen can reduce injury caused by hemorrhagic shock and resuscitation (HSR). This study investigated the therapeutic potential of hyperoxygenated hydrogen-rich solution (HHOS), a combined hydrogen/oxygen carrier, in a rat model of HSR-induced liver injury.

MATERIALS AND METHODS

Rats (n = 60) were randomly divided into 5 groups (n = 6 per group at each time point). One group underwent sham operation, and the others were subjected to severe hemorrhagic shock and then treated with lactated Ringer's solution (LRS), hydrogen-rich solution, hyperoxygenated solution, or HHOS. At 2 and 6 h after resuscitation, blood samples (n = 6) were collected from the femoral artery and serum concentrations of alanine aminotransferase and aspartate aminotransferase (AST) were measured. Rats were then sacrificed, and histopathological changes in the liver were evaluated by quantifying the percentage of apoptotic cells by caspase-3 immunohistochemistry and terminal deoxynucleotidyl transferase dUTP nick-end labeling. Inflammation was assessed by assessing malondialdehyde content and tumor necrosis factor-α, and interleukin (IL)-6 expression.

RESULTS

Compared to lactated Ringer's solution, hydrogen-rich solution, or hyperoxygenated solution groups, serum AST and alanine aminotransferase levels and IL-6, tumor necrosis factor-α, and malondialdehyde expression in liver tissue were decreased by HHOS treatment. The number of caspase-3- and terminal deoxynucleotidyl transferase dUTP nick end labeling-positive cells was decreased (P < 0.05) by HHOS treatment, 2 and 6 h after resuscitation.

CONCLUSIONS

HHOS has protective effects against liver injury in a rat model of HSR.

Intravenous oxygen: a novel method of oxygen delivery in hypoxemic respiratory failure?

INTRODUCTION

Hypoxemic respiratory failure is a common problem in critical care. Current management strategies, including mechanical ventilation and extracorporeal membranous oxygenation, can be efficacious but these therapies put patients at risk for toxicities associated with invasive forms of support. Areas covered: In this manuscript, we discuss intravenous oxygen (IVO₂), a novel method to improve oxygen delivery that involves intravenous administration of a physiologic solution containing dissolved oxygen at hyperbaric concentrations. After a brief review of the physiology behind supersaturated fluids, we summarize the current evidence surrounding IVO₂. Expert commentary: Although not yet at the stage of clinical testing in the United States and Europe, IVO₂ has been used safely in Asia. Furthermore, preliminary laboratory data have been encouraging, suggesting that IVO₂ may play a role in the management of patients with hypoxemic respiratory failure in years to come. However, significantly more work needs to be done, including definitive evidence that such a therapy is safe, before it can be included in an intensivist's arsenal for hypoxemic respiratory failure.