Optimizing Oxygen Therapy in Your Clinical Wound Practice Editorial Summary This article provides a concise overview of the role of oxygen therapy in your clinical wound practice. Oxygen is required at almost every step of the wound healing process1. Oxygen is an essential building block of cells and tissues, required for synthesis of energy, proteins, and collagen. If these building blocks are not present, tissue building, and wound healing simply cannot occur9. Oxygen is also involved in many wound healing processes, such as oxidative killing of bacteria and angiogenesis9.
Introduction
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hronic and hard to heal wounds are a silent epidemic, affecting a large percentage of the global population1. 1-2 of every 100 adults will suffer from a chronic wound in their lifetime, many suffering from multiple wounds and recurrences, and these rates will only increase with our ageing population2. In developed countries, wound care accounts for ~3% of total health care expenditures3. This translates to annual estimated costs of more than 97 billion dollars in the United States3 and 5.3 billion pounds in the UK4. The most effective way to reduce these costs is simply to heal wounds with chronicity that are considered ‘non-healing’. Yet, in practice, healing these wounds is far from simple. Despite the enormous range of readily available bandages, ointments, antimicrobial solutions, and advanced therapies targeted to wounds, the current standard of care heals less than 40% of chronic wounds by 12 weeks5. The remaining wounds continue to be a burden to both the patients and the healthcare system.
What Types of Wounds are Suitable?
Dr Aliza Lee Clinical Research Investigator, Department of Veterans Affairs Salem VA, United States
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Diabetic ulcers, vascular ulcers (venous or arterial), and pressure injuries are all chronic wounds. The pathologies underlying chronic wounds can differ widely. However, common shared features include prolonged or excessive inflammation, persistent infections, and the inability to respond to reparative stimuli6,7. Adults with vascular disease and/or diabetes are at highest risk for chronic leg and foot wounds. The ischemic (reduced tissue perfusion) and/ or hypoxic lower limb conditions which result
Wound Masterclass - Vol 1 - June 2022
from these conditions reduces availability of both oxygen and nutrients, making these wounds especially hard to heal. These wounds last on average 12 to 13 months, but this varies widely; many will remain open for years or never heal6,7, and up to 30% of Diabetic Foot Ulcers (DFUs) go on to amputation8. Even when they do heal, wounds recur in 60-70% of patients, decrease quality of life, and are a significant cause of morbidity6,7. Oxygen is required at almost every step of the wound healing process1. Oxygen is an essential building block of cells and tissues, required for synthesis of energy, proteins, and collagen. If these building blocks are not present, tissue building, and wound healing simply cannot occur9. Oxygen is also involved in many wound healing processes, such as oxidative killing of bacteria and angiogenesis9. Yet, both wound perfusion and blood oxygen levels are frequently insufficient in patients with chronic wounds due to poor circulation, vascular disruption, and vasoconstriction, thereby reducing the wound’s capacity to heal.Novel wound care therapies that specifically address these underlying issues are sorely needed. Fortunately, there is a growing body of evidence to support the benefits of supplementary oxygen therapy on wound healing10-12. When physiological constraints hinder adequate oxygenation, various methods can be used to direct exogenous oxygen to the wound in a therapeutic context. Skin wounds can receive oxygen from the blood stream via perfusion and from oxygen uptake through the skin13. Raising oxygen concentrations can, by itself, trigger healing responses through the mechanisms