Outcomes of Debridement in Diabetic Foot Ulcers Treated With Continuous Diffusion of Oxygen

Review: Does Debridement Improve Clinical Outcomes in People With Diabetic Foot Ulcers Treated With Continuous Diffusion of Oxygen?

Temple University School of Podiatric Medicine
January 15, 2021

Keywords

Debridement

Chronic Wounds

Biofilm

Necrotic Wounds

Introduction

Chronic wounds require an increased amount of oxygen to help with cellular function and growth. They often manifest with biofilm, slough, and necrotic tissue, all of which deprive cells of the oxygen they need to perform vital functions. Various forms of debridement are commonly employed to rid wounds of pathological tissues that negatively affect cellular communication and growth. Sharp surgical debridement is most frequently performed by physicians. Continuous diffusion of oxygen (CDO) involves the use of humidified, purified air at 3mL/hour in conjunction with moist wound therapy (MWT) dressing. A previous paper by Niederauer et al. published in 2018 in the Journal of Wound Care, described using CDO for healing DFUs. This study showed that CDO improved the healing rate of DFUs in terms of time, chronicity, and weight-bearing ability when compared to a placebo. Additionally, the previous paper described wound size, chronicity, and adverse events.¹

Methods

In a double-blind, placebo-controlled, randomized study, Lavery et al. analyzed 146 patients with diabetic foot ulcers (DFU) and assessed debridement with concomitant use of CDO over 12 weeks. Debridement was categorized as surgical removal of non-viable tissue to expose a bleeding wound bed. Before patients began the study, there was a two-week evaluation period. During this time, the authors performed standard wound care consisting of debridement, dressings, and offloading techniques. The authors of this article controlled many variables throughout the study. The standard dressing consisted of a single foam covered by an occlusive barrier. In wounds with high drainage, a calcium alginate dressing was used to control excess exudate. All ulcers were surgically debrided and offloaded with an offloading walker. Patients with more than 50% closure during the pre-trial period were excluded from the study.

Debridement: When and Why?

This study consisted of 33 different medical facilities. The facilities debrided wounds at a total of 90.0% of visits. However, one site, deemed Site X, had a significantly lower frequency of surgical debridement at 41.3% of visits. By removing Site X from the data set, the debridement per visit increased to 98.4% at the other 32 facilities. The implementation of surgical debridement of DFUs was up to the discretion of the physician based on their professional assessment. Additionally, surgical debridement with CDO therapy led to closure of 46.2% of DFUs in 12 weeks compared to 22.6% of DFUs with surgical debridement and placebo CDO throughout the 33 facilities. With Site X data removed, debridement and CDO therapy led to closure of 51.2% of wounds, and placebo CDO led to closure of only 22.6%. This is significant because it shows that with Site X data removed, the group with high debridement and CDO therapy increased wound closure in 12 weeks (46.2% to 51.3%), and the group with placebo CDO and debridement decreased (22.6% to 21.3%).

Site X and the placebo were not statistically different in healing at 12 weeks due to the decreased frequency of debridement. Overall, this study demonstrated that a high debridement per visit percentage with CDO therapy increased wound closure at 12 weeks. This suggests that non-viable tissue inhibits CDO therapy and debridement is critical for its efficacy.

Conclusion

One intriguing point of the study is that Site X’s patients were 95.5% Hispanic. In the complete data set, Hispanic patients had a decreased rate of healing at 12 weeks in comparison with other ethnicities because of the high percentage at Site X. However, with Site X removed, there was no difference in the healing rate based on ethnicity. Wound rate closure of Hispanic patients at Site X compared to other sites in the study was 21.4% versus 81.8%, respectively. This suggests that the differences in wound closure were due to facility differences rather than ethnicity. One considerable limitation of this study is the reliability of the self-reported debridement and the quality of the debridement. Overall, this is a well-controlled study showing the effectiveness of frequent surgical debridement in conjunction with CDO improved the healing rates of DFUs.

Reference

Niederauer MQ, Michalek JE, Liu Q, Papas, Lavery LA, Armstrong DG. Continuous diffusion of oxygen improves diabetic foot ulcer healing when compared with a placebo control: a randomized, double-blind, multicentre study. J Wound Care. 2018;27(Suppl 9): S30–S45.

About The Author

Grant Schindler is a third-year podiatric medical student at Temple University School of Podiatric Medicine (TUSPM) in Philadelphia, Pennsylvania. He is a 2016 graduate of the University of Sioux Falls in South Dakota, where he earned his Bachelor of Arts in Biology. Outside of academics, Grant worked part-time for a local podiatrist. The hands-on patient care and the ability to specialize early are some of the reasons Grant chose to become a podiatrist. In 2017, Grant enrolled in TUSPM and shortly after became involved in several school organizations. As the current President of Wound Care Club, Grant has organized biopsy, wound dressing, and graft workshops for the members of the club. In the upcoming year, Grant is excited to expand his knowledge and continue to learn throughout his fourth-year rotations. Dr. James McGuire is the director of the Leonard S. Abrams Center for Advanced Wound Healing and an associate professor of the Department of Podiatric Medicine and Orthopedics at the Temple University School of Podiatric Medicine in Philadelphia.

The views and opinions expressed in this content are solely those of the contributor, and do not represent the views of WoundSource, HMP Global, its affiliates, or subsidiary companies.