Oxygen therapies and their effects on wound healing

Abstract

Oxygen is an important factor for wound healing. Although several different therapies investigated the use of oxygen to aid wound healing, the results of these studies are not unequivocal. This systematic review summarizes the clinical and experimental studies regarding different oxygen therapies for promoting wound healing, and evaluates the outcomes according the methodological details. A systematic literature search was conducted using Embase, Medline, Web of Science, Cochrane, PubMed publisher, and Google Scholar libraries. Clinical and experimental studies investigating oxygen for wound healing were selected. Included articles were categorized according to the kind of therapy, study design, and wound type. The methodological details were extracted and analyzed. Sixty-five articles were identified and divided in three different oxygen therapies: Local oxygen therapy, hyperbaric oxygen therapy, and supplemental inspired oxygen therapy. More than half of the included local oxygen and hyperbaric oxygen studies had one or more significant positive outcomes, 77 and 63%, respectively. Supplemental inspired oxygen therapy during gastrointestinal and vascular surgery was more likely to have a positive result than during other surgical interventions reducing surgical site infections. These many positive outcomes promote the use of oxygen treatment in the stimulation of wound healing. However, the lack of clinical studies and vast methodological diversity made it impossible to perform a proper comparison within and between the different therapies. Further randomized clinical studies are warranted to examine the value of these therapies, especially studies that investigate the more patient-friendly oxygen dressings and topical wound oxygen therapies. Also, to achieve more solid and consistent data, studies should use more standardized methods and subjects.

Update on management of diabetic foot ulcers

“…45 Many patients with DFUs have impaired oxygenation to wounded areas, especially in the setting of vascular disease. Therapeutic strategies to correct this include local delivery of oxygen to the wound and systemic oxygen administration.…”

“…This mode of treatment has been studied primarily in surgical wounds and has not been well studied in DFUs. 45 Hyperbaric oxygen (HBOT) is administered in a compression chamber, which provides 100% oxygen and delivers a greatly increased partial pressure of oxygen to tissues. A 2015 Cochrane review that pooled data from 10 RCTs showed that there was a significant increase in rate in healing with HBOT at 6 weeks, although this benefit was not evident at follow-up at 1 year.…”

Nano‐hydrogel embedded with quercetin and oleic acid as a new formulation in the treatment of diabetic foot ulcer: A pilot study

“…In fact, Qu by itself has strong antimicrobial and antioxidant activity, [29][30][31] while AO increases the expression of vascular endothelial growth factoralpha (VEGF-α) and interleukin-1beta (IL-1β). 32 Finally, several authors documented that the treatment of DFUs accounts for approximately one-third the total cost of diabetic care, 33 but only few patients, about 20%, have unhealed DFUs at 1 year 34,35 and about 40% have a recurrence in 1 year. 18 Even if in our study we do not performed an economic evaluation, we can affirm that the topical treatment was performed at home and did not require other treatment or hospitalisation, and also no recurrence occured, suggesting that this treatment could be cost/saving.…”

Characterisation of impaired wound healing in a preclinical model of induced diabetes using wide‐field imaging and conventional immunohistochemistry assays

“…Molecular oxygen is also necessary for collagen synthesis during the remodelling phase. 23 Diabetic hyperglycaemia can negatively affect the microvasculature by causing endothelial cell damage, causing abnormal vascular function, reducing perfusion, and decreasing oxygen and nutrient delivery to the wound. 24 As such, the ability to monitor parameters related to tissue oxygenation has the potential utility to non-invasively assess healing.…”

“…During the inflammatory phase, oxidant levels increase via Nicotinamide adenine dinucleotide phosphate (NADPH)‐linked oxygenase, consuming high amounts of oxygen, and oxygen limitation can prolong the inflammatory phase. Molecular oxygen is also necessary for collagen synthesis during the remodelling phase …”