Objective: The present study is to evaluate the effect of normobaric oxygen therapy on wound healing in patients who presented with minor tissue loss from critical limb ischemia.

Materials and Methods: This randomized controlled trial was conducted at Ramathibodi Hospital. From May 2017 to January 2018,
critical limb ischemia patients with minor tissue loss were randomly assigned to be treated with or without normobaric oxygen therapy for four weeks. The primary outcome is to evaluate the wound healing by measuring the wound surface area. The secondary
outcome is to evaluate the change in the transcutaneous oxygen tension at pre- and post-treatment and also complications from the
treatment.

Results: We assigned 28 patients with minor tissue loss into two groups (after excluding one patient from each group due to infection): 14 patients each group. The wound surface area at four-week times was smaller in intervention group (-0.06+1.25 cm2) but was larger in control group (0.825+1.10 cm2) without statistical significance (p = 0.057). Likewise, the transcutaneous oxygen
tension in the intervention group showed superior result compared to the control group (3.22+9.54 vs. -3.02+7.25 mmHg) though
there was no statistical significance (p = 0.059).

Conclusion: Normobaric oxygen therapy may be beneficial for increasing wound healing in the critical limb ischemia patients who
presented with minor tissue loss.

Keywords: Critical limb ischemia, Wound healing, Oxygen therapy, Minor tissue loss