Gas gangrene

In the gas fire ( Ex.: gas gangrene, Gasödem, Gasphlegmone, clostridium myositis and cellulitis, clostridial myonecrosis, malignant edema) is a fast arising, infectious -toxic disease ( infectious disease ) by extreme danger. The reason is a local soft tissue infection with gas-forming clostridia. Must be differentiated purulent mixed infections, which can also form sometimes gas (such as necrotizing fasciitis or not caused by clostridial cellulitis ), but primarily and mainly not decompose the muscles have a different symptoms and also have a better prognosis. In these, the following mentioned pathogens also play no dominant role.

Pathogen

The important here clostridial species ( Clostridium perfringens (90 % of cases), Clostridium septicum, Cl. Histolyticum, Cl. Novii, Cl. Fallax, Cl. Bifermentans, Cl. Sordellii ) occur in nature everywhere ( ubiquitous ). They are obligate anaerobic gram- positive spore-forming bacteria, which are found in the human intestine, where they are but not pathogenic under normal conditions (disease- causing).

The pathogenicity arises only with the change of environmental conditions on an anaerobic environment (lack of oxygen ) as it exists in a destroyed soft tissues with reduced oxygen partial pressure.

Pathogenesis

Mostly due to injury very dirty, destroyed and fissured tissue areas of the place where the clostridia regain their pathogenicity, so where develop from spores of bacteria which then multiply.

Basically, the lack of oxygen is ( Clostridia are anaerobic pathogens ). Favoring the reduced blood flow by soft tissue contusion, tissue death (necrosis ), shock, comorbidities such as diabetes mellitus and malignant tumors. In addition, the contamination of the wound brings an infection with aerobic ( oxygen consuming ) organisms of what promotes the lack of oxygen in the infected tissue and improves living conditions for clostridia.

Clostridia form various exotoxins that cause cell membrane destruction and edema in the surrounding tissue, thus leading to a vicious circle filters ( vicious circle ) another breeding ground for pathogens available except CO2. In addition exotoxins of Clostridium act on white blood cells (leukocytes) function locking up to inactivating. They also promote the closure of small blood vessels by thrombosis, which reinforces the lack of oxygen in the affected tissue through a circulatory disorder and further promotes optimal for clostridial growth medium.

Symptoms

After an incubation period of 5 to 48 hours falls by surgery or soft tissue injuries, a rapidly spreading wound infection ( redness, heat in the wound area ), which is extremely painful.

In most cases, at palpation ( palpation ) is the wound environment to hear a noticeable crackling and feel: a subcutaneous emphysema due to CO2 formation ( Hautkrepitation ).

From drainages often emptied a bloody - blackish, frothy, sweet - foul smelling secretion. The affected muscles of gray red color and is compared in appearance with cooked beef.

The general condition of the patient, is characterized by a rapidly progressive septic disease, with tachycardia, coagulopathy (blood - clotting disorder ), circulatory failure, respiratory disorders, and hemolytic anemia due to the decomposition of red blood cells by toxins of clostridia. In addition, acute renal failure and liver dysfunction ( multiple organ failure ).

Diagnosis

Due to the rapid and fatal course of the untreated disease and the need for immediate, but at the same time engaging therapy to amputation of extremities, the diagnosis must be made promptly and safely.

The diagnosis is based on as many individual findings of the clinical picture and x-ray (character: " feathered " muscles) provided and secured by the microscopic detection of pathogens from a Muskelquetschpräparat. Alternative pathogen from culture, histology and other radiological methods are used, are methodologically limited but usually too late.

Therapy

The therapy is based on four pillars:

• Surgical intervention ( surgery)
• Antibiotic Therapy
• Hyperbaric oxygenation
• Intensive Care Medicine

The therapy must already begin with suspicion.

Surgical intervention

Goals of surgery:

Due to the drama and danger of the disease process, the life support often takes precedence over the cosmetic and functional outcome is even granted.

Antibiotic Therapy

Antibiotic therapy should be initiated before the results of susceptibility testing are known. Due to the generally present mixed infection combinations of high-dose broad-spectrum antibiotics and antibiotics are used with activity against anaerobes. An example of combination according to this basis is penicillin G and metronidazole.

Hyperbaric oxygenation

The gas fire is a standard indication for the use of oxygen over- pressure chambers.

This therapy aims to increase due to extremely high partial pressures of oxygen in the surrounding atmosphere by diffusion, neglecting the blood flow to the O2 partial pressure in the infected tissue. So you cut the obligate anaerobic germ livelihoods and hopes with this elegant, but logistically demanding a rescue treatment of life and the preservation of limbs.

One problem is the time factor: heavy sufferers are hardly transportable and hyperbaric chambers are rare even with the inclusion of cooperating military facilities. Initial often remains only an aggressive surgical procedure.

Intensive Care Medicine

Due to the effects of the pathogen exotoxins it comes to multi-organ failure. For stabilizing treatment patient ventilation, treatment with catecholamines and other intensive medical therapy and monitoring methods are often necessary.

• Bacterial infectious disease of humans
• Diving Medicine
• Disease in surgery