The role of hyperbaric oxygen therapy in the treatment of diabetic foot ulcers: a systematic review with meta-analysis of randomized controlled trials on limb amputation and ulcer healing

Introduction: Hyperbaric oxygen therapy (HBOT) is increasingly being used in the treatment of as diabetic foot ulcers (DFU). However, definitive evidence regarding its beneficial effects is still scarce. The present systematic review aims to analyze the role of HBOT in the prevention of limb amputation along with improvement of ulcer healing in patients with lower limbs DFU. Evidence acquisition: Three databases were searched: PubMed, Scopus, and ISI Web of Knowledge. The search was enrolled during October 2020. Both titles and abstracts were examined by two independent reviewers. Only randomized controlled trials (RCTs) reporting a comparison between standard DFU treatment and standard treatment associated with HBOT were included. In all studies eligibility was assessed and data regarding studies characteristics, methods and considered outcomes was obtained. Odds ratio (OR) was used to evaluate amputation and complete ulcer healing rates. Percentage of ulcer reduction at two weeks was evaluated using the inverse variance method, and the values were compared using mean difference values. Meta-analysis was done using a fixed-effect model if I-2 values were under 50%, and a random-effects model if not. Evidence synthesis: Eleven RCTs were included, with a total of 668 patients studied. Patients undergoing HBOT had lower risk of amputation (OR 0.53 95% CI 0.32-0.90, I-2=31%). No difference was found in minor amputations (OR 0.89 95% CI 0.35-2.24, I-2=69%). Regarding, healing rates, HBOT patients had greater chances of ulcer healing (OR 4,00 95% CI 1.54-10.44, I-2=70%). It has also shown higher percentage of ulcer area reduction after two weeks of treatment in the HBOT group (mean difference 23.19%; 95% CI 14.86-31.52; I-2=0%). Conclusions: The present review offers evidence that adjuvant HBOT decreases risk of major amputation while promoting wound healing when combined to standard treatment in the management of DFU. These findings may have clinical relevance in a selected group of patients, yet further larger studies are still needed.