What is the effect of hyperbaric oxygen therapy on necrotic tissue?

From the Guidelines

Hyperbaric oxygen therapy (HBOT) should be considered as an adjunctive treatment for necrotic tissue in patients with necrotizing soft-tissue infections (NSTIs) after prompt debridement. This recommendation is based on the 2018 WSES/SIS-E consensus conference, which suggests considering adjuvant hyperbaric oxygen therapy in patients with NSTI after prompt debridement 1. HBOT involves breathing pure oxygen in a pressurized chamber, typically at 2-3 times normal atmospheric pressure, which increases oxygen levels in the blood and tissues, stimulating angiogenesis, enhancing white blood cell activity, and promoting fibroblast proliferation for tissue repair.

Benefits of HBOT

• Increases oxygen tension in tissues, helping to demarcate viable from non-viable tissue and making surgical debridement more precise
• Enhances white blood cell activity to fight infection
• Promotes fibroblast proliferation for tissue repair
• May reduce mortality in patients with NSTIs, as shown in a retrospective study of 45,913 patients 1

Important Considerations

• HBOT should not interfere with standard treatment and should not delay prompt debridement and other necessary interventions
• The patient should not be transferred to carry out HBOT therapy, thereby delaying standard care
• HBOT is typically administered in daily sessions of 90-120 minutes for 20-40 treatments, depending on the severity and response

Context and Limitations

• The evidence for HBOT in necrotic tissue is largely based on retrospective studies and expert consensus, with a lack of high-quality, randomized controlled trials 1
• HBOT should be used as an adjunctive therapy alongside appropriate wound care, debridement of necrotic tissue, infection control, and management of underlying conditions.

From the Research

Hyperbaric Oxygen Therapy for Necrotic Tissue

• Hyperbaric oxygen therapy (HBOT) has been shown to increase survival in cases of necrotizing soft tissue infections 2.
• The therapy uses high pressures to saturate hemoglobin and dissolve oxygen into blood plasma, creating a hyperoxemic environment to nourish and reverse local tissue injury caused by ischemia and hypoxemia 3.
• HBOT is an adjuvant wound therapy that has been suggested to be beneficial for the healing of wounds for over 40 years, with its ability to increase the arterial partial pressure of oxygen in the human body and facilitate oxygen transport when the body's oxygen transport system has been compromised 4.

Mechanisms and Applications

• The mechanisms by which HBOT acts are well understood, and it is effective in enhancing the rate and effectiveness of healing of a variety of wounds and injuries 5.
• HBOT consists of using pure oxygen at increased pressure, leading to augmented oxygen levels in the blood and tissue, and exerting antimicrobial, immunomodulatory, and angiogenic properties, among others 6.
• The therapy has been shown to be beneficial in the healing of diabetic foot ulcers, and has potential applications in inflammatory and systemic maladies, COVID-19, and cancer 6.

Benefits and Risks

• HBOT has been associated with a significant survival benefit in patients with necrotizing soft tissue infections, particularly in the sickest patients 2.
• The therapy is expensive and not without risk, and the underlying etiology for the presenting diagnosis must be adequately treated before starting HBOT as an adjunct therapy to get maximum benefit 3.
• Adverse effects and contraindications associated with HBOT must be considered, and further research is needed to extend the possible uses of this procedure 6.