Topical oxygen therapy for treating diabetic foot ulcers: a WHAM evidence summary

Topical oxygen therapy is an adjunctive therapy that seeks to improve cell proliferation in chronic wounds by delivering high concentration oxygen directly to the wound bed. Oxygen application can be via a mechanical system that delivers gaseous oxygen to the wound bed (carrier systems) or can be via topical applications (e.g., oxygen generating/ releasing dressings or haemoglobin spray) that directly or indirectly increase oxygen in the wound bed. Level 1 evidence consisting of five meta-analyses1-5 on the effectiveness of mechanically delivered topical oxygen therapy demonstrated that the treatment is associated with statistically significant improvements in complete healing at 12 weeks2-5, and in the number of DFUs healed at 8—12 weeks1. These findings are supported by a narrative systematic review6, although a seventh, narrative review7 concluded that the evidence was inadequate to make recommendations. There is evidence that topical oxygen therapy delivered via mechanical systems is associated with improvement in wound healing at 12 weeks with differences over standard care of between 5% and 27%2, which may be clinically significant for some people with DFUs. Two Level 1 reviews8, 9 reported narrative results from Levels 2, 3 and 4 studies on effectiveness of haemoglobin spray for treating DFUs, but this body of evidence is currently inadequate to recommend this method of topical oxygen delivery. CLINICAL PRACTICE RECOMMENDATIONS