Continuously Diffused Therapy for Wound Healing

Key Message

What Is the Issue?

• Wounds are prevalent across health care settings, costing Canada an estimated $12 billion per year in wound care. Chronic wounds (wounds that do not heal in the typical amount of time, which can depend on the size and type of wound) can have a significant impact on a patient’s quality of life and health.
• Healing tissue has a high need for oxygen. Oxygen can be delivered in several ways, including topical oxygen therapy, which delivers oxygen directly to the wound. One type of topical oxygen therapy is continuously diffused oxygen (CDO) therapy, which uses a device that takes oxygen from the air and then delivers pure, humidified oxygen to the wound.
• We previously completed a Rapid Review on CDO therapy for wounds in 2020. This review aimed to determine if new evidence has since been published on this topic.

What Did We Do?

• To inform decisions about CDO therapy for wound healing, we sought to identify and summarize literature comparing the clinical effectiveness and cost-effectiveness of CDO therapy versus conventional wound care. We also attempted to identify evidence-based recommendations for the use of CDO therapy.
• We searched key resources, including journal citation databases, and conducted a focused internet search for relevant evidence published since 2019. One reviewer screened articles for inclusion based on predefined criteria, critically appraised the included studies, and narratively summarized the findings.

What Did We Find?

• CDO therapy appears to be clinically effective for treating patients with diabetic foot ulcers, particularly chronic or hard-to-heal ulcers that have not responded to standard care. Rates of adverse events were comparable between patients receiving CDO and patients receiving standard care. Two cost-effectiveness studies reported that CDO is likely to be cost-effective compared to standard care for patients with chronic, hard-to-heal diabetic foot ulcers.
• We identified fewer studies for other types of wounds. Preliminary evidence suggests that CDO therapy may be helpful for patients with other types of wounds that are chronic or have not responded to standard care. Reporting on adverse events was limited.
• Limited evidence suggests that patients receiving CDO therapy had better outcomes if their wound was debrided more frequently as well as if they received CDO therapy for a longer time.
• The evidence-based guidelines recommend the use of topical oxygen therapy (of which CDO is a subtype) for treating diabetic foot ulcers that have failed to heal with standard care. One guideline suggested that topical oxygen therapy may be considered for other types of non-neoplastic, hard-to-heal wounds.
• We did not find cost-effectiveness evidence for wounds other than diabetic foot ulcers that met the inclusion criteria for our report. We also did not identify any clinical effectiveness or cost-effectiveness evidence, or any guidelines regarding the use of CDO to treat First Nations, Inuit, and Métis patients, that met the inclusion criteria for our report.

What Does This Mean?

• CDO therapy may be beneficial and more cost-effective than standard care for patients with hard-to-heal, chronic diabetic foot ulcers that have not responded to standard care. Evidence-based guidelines also recommend the use of CDO therapy for this patient population.
• The clinical effectiveness and cost-effectiveness of CDO therapy for other types of wounds is still unclear. It is also unclear if there is an optimal way to provide CDO (e.g., oxygen flow rate, debridement, length of treatment).
• We identified limited evidence that reported on patient ethnicity. Considering that some groups, including First Nations, Inuit, and Métis Peoples, have higher rates of diabetes than the overall population in Canada — which may lead to higher rates of diabetic foot ulcers — decision-makers involved in implementing CDO therapy should consider ways to ensure equitable access for all patients who may need this treatment.