Clostridial myositis and myonecrosis is an acute, rapidly progressive infection of the soft tissues commonly known as “gas gangrene.” The infection is caused by one of several bacteria in the group known as “clostridium.” While more than 150 species of clostridium have been identified, only a few commonly cause gas gangrene. The infection typically spreads from a discrete focus of clostridium within the body. The original source can actually be within the body, as clostridium bacteria normally live in the gastrointestinal tract. Alternatively, the infection can originate outside the body, for example, when an infection results from contamination of wounds during trauma such as a motor vehicle accident.
Gas gangrene infection is severe and can advance quickly. Besides replicating and migrating, the organisms which cause gas gangrene produce poisons known as exotoxins. Exotoxins are capable of liquefying adjacent tissue and inhibiting local defense mechanisms which might normally contain a less virulent infection. As such, the advancing infection of gas gangrene may simply destroy healthy tissue in its path and spread over the course of hours.
Clostridium bacteria are “anaerobic,” meaning that they prefer low oxygen concentrations to grow. If clostridium bacteria are exposed to high amounts of oxygen, their replication, migration and exotoxin production can be inhibited. This is why hyperbaric oxygen is used in the treatment of gas gangrene. Repeated treatment in the hyperbaric chamber has the potential to slow the progress of the infection while the two primary therapies, antibiotics and surgical removal of the infected tissue, control it.
The advantages of hyperbaric oxygen treatment in gas gangrene are two-fold. First, it may be lifesaving because the exotoxin production is rapidly halted and less surgery may be needed in gravely ill patients. Second, it may save tissue and limbs, possibly preventing limb amputation that might otherwise be necessary.