Cyclical pressurized topical wound oxygen therapy increased healing of refractory diabetic foot ulcers
An industry-funded randomized trial showed that topical wound oxygen therapy is efficacious, but more data on effectiveness, outcomes, and cost are needed, an ACP Journal Club commentary said.
Topical wound oxygen (TWO2) therapy healed more refractory diabetic foot ulcers than sham therapy, according to an industry-funded study. The randomized trial included 73 patients before its enrollment was halted based on the effectiveness of the intervention. At 12 weeks, the active TWO2 arm had a wound closure rate of 41.7% compared to 13.5% with sham therapy. At 12 months, the rates were 56% and 27%, respectively.
The study was published online Oct. 16, 2019, and in print Feb. 20 by Diabetes Care. The following commentary by Aris Liakos, MD, MSc, PhD, Paraskevi Liakopoulou, BScN, MSc, and Apostolos Tsapas, MD, PhD, MSc, was published in the ACP Journal Club section of the March 17 Annals of Internal Medicine.
Evidence for hyperbaric oxygen therapy (HBOT) as an adjunct for nonhealing ischemic diabetic foot ulcers is conflicting. TWO2 therapy could offset some of the burdens associated with HBOT. It is available for home use; is suitable for patients with claustrophobia; and avoids potential complications of HBOT, such as barotrauma, ocular side effects, and central nervous system toxicity.
The TWO2 study by Frykberg and colleagues showed a benefit in the clinically important end point of complete ulcer closure at 12 weeks with TWO2 therapy vs sham. The trial was stopped early for benefit based on the Pocock stopping rule, which uses the same level of significance (P=0.022 in this study) at each equally spaced interim analysis. This is regarded by some statisticians as unsafe for stopping early, especially in a moderate-sized trial. Variation in wound care practice across study sites in this multinational trial could have confounded the results.
The trial shows that TWO2 therapy is efficacious for hard-to-heal diabetic foot ulcers as an adjunct to comprehensive wound care for ≥4 weeks. The effectiveness of TWO2 therapy as first-line therapy alongside best wound care practice and in patients with limb ischemia or osteomyelitis is unknown. Evidence is also lacking about the effect of TWO2 therapy on amputations and quality of life. Cost-effectiveness analyses are needed for policymakers to guide reimbursement of wound care products, but such studies would require larger sample sizes to provide precise estimates and should assess variations across study sites.