Necrotising Soft Tissue Infections (Including Necrotising Fasciitis and Gas Gangrene)
Necrotising soft tissue infections (NSTIs) are rare but extremely serious infections that spread rapidly through the skin, fat, fascia (the tissues surrounding muscles), and sometimes muscle itself. They can cause severe tissue damage and can become life-threatening if not treated urgently.
Early diagnosis and treatment are crucial.
NSTIs may develop following trauma, surgery, burns, insect bites or even minor breaks in the skin. They can occasionally occur without an obvious injury. While anyone can develop an NSTI, risk factors include:
- Diabetes
- Smoking
- Obesity
- Excess alcohol consumption
- Peripheral vascular disease
- Immunosuppression
- Intravenous drug use
Symptoms
One of the earliest warning signs is severe pain that seems out of proportion to the appearance of the affected area.
Other symptoms may include:
- Rapidly increasing swelling
- Redness or skin discolouration
- Fever and chills
- Feeling generally unwell
- Blistering of the skin
- Numbness as nerves become damaged
- Confusion or drowsiness in severe cases
Treatment
NSTIs require emergency treatment. This normally includes:
- Urgent surgical removal of infected and dead tissue (debridement)
- Intravenous antibiotics
- Intensive care support where required
More than one operation is often needed to fully control the infection. In severe cases, amputation may be necessary to prevent life-threatening spread of infection.
How Can Hyperbaric Oxygen Therapy Help?
Hyperbaric Oxygen Therapy (HBOT) may be used as an additional treatment alongside surgery and antibiotics in selected patients with severe necrotising soft tissue infections.
During HBOT, patients breathe oxygen at increased pressure within a specialised chamber. This significantly increases the amount of oxygen delivered to infected and injured tissues.
Potential benefits include:
- Improving oxygen delivery to damaged tissue
- Supporting the body's ability to fight infection
- Reducing tissue swelling
- Helping limit the effects of certain bacterial toxins
- Supporting wound healing
HBOT does not replace surgery or antibiotics but may be used as part of a multidisciplinary treatment plan where appropriate.
Clostridial Myonecrosis (Gas Gangrene)
Clostridial myonecrosis, commonly known as gas gangrene, is a rapidly progressive infection caused by bacteria of the Clostridium species, most commonly Clostridium perfringens.
The infection destroys muscle tissue and produces gas within affected tissues. It is most commonly associated with traumatic injuries but can also occur following surgery or other tissue damage.
Symptoms
Symptoms can include:
- Severe pain
- Rapidly increasing swelling
- Skin discolouration
- Fluid discharge from wounds
- Gas within the tissues
- Fever and signs of sepsis
- Rapid deterioration in a patient's condition
Treatment
Gas gangrene is a surgical emergency.
Treatment usually involves:
- Emergency surgical debridement
- Intravenous antibiotics
- Intensive care support where required
- Hyperbaric Oxygen Therapy in selected patients
How Can Hyperbaric Oxygen Therapy Help?
Hyperbaric oxygen inhibits the growth of oxygen-sensitive bacteria such as Clostridium species and can reduce toxin production. It also improves tissue oxygenation and supports the body's immune response.
When used alongside prompt surgery and antibiotics, HBOT may help limit tissue damage and improve the chances of preserving healthy tissue.
Access to Hyperbaric Oxygen Therapy
Hyperbaric Oxygen Therapy may be considered for selected patients as part of their overall treatment plan. Because treatment takes place at DDRC Healthcare rather than within the acute hospital, each patient's condition must be carefully assessed before transfer. For critically ill patients, the treating intensive care team and hyperbaric specialists will work together to determine whether the potential benefits of treatment outweigh the risks of transport.
HBOT is used in addition to, and not instead of, surgery, antibiotics and intensive care treatment. Not all patients with necrotising soft tissue infections will be suitable candidates for transfer and treatment.
Necrotising Soft Tissue Infection (NSTI)
Necrotising soft tissue infections represent a spectrum of rapidly progressive infections affecting skin, subcutaneous tissue, fascia and, in some cases, muscle. They include necrotising fasciitis and clostridial myonecrosis (gas gangrene).
These infections are associated with significant mortality and morbidity and require prompt recognition and urgent multidisciplinary management.
Standard Management
Definitive management remains:
- Early recognition and diagnosis.
- Aggressive surgical source control and debridement.
- Broad-spectrum intravenous antimicrobial therapy.
- Critical care support where indicated.
Repeated surgical exploration and debridement are frequently required.
Hyperbaric Oxygen Therapy
Hyperbaric oxygen therapy is recognised as an adjunctive treatment for selected patients with necrotising soft tissue infections, particularly clostridial myonecrosis and severe necrotising fasciitis.
Potential mechanisms include:
- Increased tissue oxygen tensions in hypoxic tissues.
- Enhanced neutrophil oxidative killing.
- Reduction in tissue oedema.
- Improved fibroblast function and angiogenesis.
- Inhibition of toxin production by anaerobic organisms, particularly Clostridium perfringens.
HBOT should never delay urgent surgical intervention and should be integrated with surgical, microbiological and critical care management.
Referral
Patients with confirmed or strongly suspected necrotising soft tissue infection may be considered for urgent hyperbaric assessment following discussion with the hyperbaric medicine team.
Further information regarding referral pathways and funding arrangements can be found [here].
Patient Selection and Referral Considerations
Hyperbaric oxygen therapy is an adjunctive treatment and should not delay urgent surgical source control, antimicrobial therapy or critical care management.
Patients being considered for HBOT should be discussed with the DDRC Hyperbaric Medicine team and the referring Intensive Care Consultant. The potential benefits of treatment must be balanced against the risks associated with transfer from a critical care environment.
DDRC Healthcare is located off-site from the main acute hospital. Although appropriate medical support, including anaesthetic cover, is available during treatment, transferring critically ill patients outside the hospital environment carries inherent risks that are similar to those considered when transporting intensive care patients for investigations or procedures elsewhere within the healthcare system.
For this reason, referral decisions are made on an individual basis following multidisciplinary discussion between the treating team, intensive care clinicians and DDRC hyperbaric physicians. Patients should be sufficiently stable to undergo transfer and treatment, and the anticipated benefits of HBOT should outweigh the risks associated with transport and temporary treatment away from the critical care unit.