Revisiting the essential role of oxygen in wound healing

Hypoxemia, caused by disrupted vasculature, is a key factor that limits wound healing. Correcting hypoxemia through the administration of supplemental oxygen (O2) can have significant beneficial impact on wound healing in the perioperative and outpatient settings. Beyond its role as a nutrient and antibiotic, O2 may support vital processes such as angiogenesis, cell motility, and extracellular matrix formation. Recent discoveries highlight a novel aspect, addressing the role of O2 in wound healing via the production of reactive oxygen species (ROS). Almost all wound-related cells possess specialized enzymes that generate ROS (including free radicals and H2O2) from O2. Defect in these enzymes is associated with impaired healing. Low wound pO2 is expected to compromise the function of these enzymes. At low concentrations, ROS serve as cellular messengers to support wound healing. The use of systemic hyperbaric O2 therapy presents potential advantages, as well as risks. There is evidence to suspect that the use of pressure and systemic pure O2 may not be essential in wound care. Elimination of these factors by using sub-pure systemic O2 under normobaric conditions may significantly minimize the risk of O2 toxicity. Furthermore, opportunities to treat dermal wounds using topical O2 therapy warrant further investigation. Given that many growth factors require ROS for their function, it is reasonable to assume that approaches to correct wound pO2 will serve as an effective adjunct in treating chronic wounds.