Topical oxygen therapy in the treatment of diabetic foot ulcers: a multicentre, open, randomised controlled clinical trial

Objectives: Perfusion and blood oxygen levels are frequently insufficient in patients with hard-to-heal wounds due to poor circulation, vascular disruption and vasoconstriction, reducing the wound's capacity to heal. This study aimed to investigate the effect of topical oxygen on healing rates in patients with hard-to-heal diabetic foot ulcers (DFUs) (i.e., non-responsive over four weeks). Method: This multicentre, open-label, community-based randomised clinical trial compared standard care (SOC) with or without continuous topical oxygen therapy (TOT) for 12 weeks in patients with DFUs or minor amputation wounds. SOC included debridement, offloading with total contact casting (TCC) and appropriate moisture balance. Primary endpoints were the number of patients to achieve complete wound closure and percentage change in ulcer size. Secondary endpoints were pain levels and adverse events. Results: For the study, 145 patients were randomised with index ulcers graded Infectious Diseases Society of America (IDSA) 1 or 2, or Wagner 1 or 2. In the intention-to-treat analysis, 18/64 (28.1%) patients healed in the SOC group at 12 weeks compared with 36/81 (44.4%) in the SOC plus TOT group (p=0.044). There was a statistically significant reduction in wound area between the groups: SOC group mean reduction: 40% (standard deviation (SD) 72.1); SOC plus TOT group mean reduction: 70% (SD 45.5); per protocol p=0.005). There were no significant differences in changes to pain levels or adverse events. Conclusion: This study suggests that the addition of TOT to SOC facilitates wound closure in patients with hard-to-heal DFUs.