Infected wounds are wounds in which bacteria or other microorganisms have colonized, causing either a delay in wound healing or deterioration of the wound. Most wounds are typically contaminated by bacteria. However, infected wounds result when the body's immune defenses are overwhelmed or cannot cope with normal bacterial growth. Infection of wounds caused by surgery is a serious health risk, as studies have shown that 70 percent of the deaths of patients who have undergone surgery are caused by surgical site infections.
Most cases of infected wounds are caused by bacteria, originating either from the skin, other parts of the body or the outside environment. The skin contains bacteria (normal flora) which are normally harmless if the skin is intact. However, the protective barrier formed by the skin is disrupted when there is a wound, and these normal flora are able to colonize the injured area. This results in further tissue damage and may prolong wound healing by promoting more inflammation, which prolongs the process of wound healing.
The most common bacteria causing wound infection is Staphylococcus aureus and other groups of staphylococci. Contamination from other parts of the body may also cause wound infection. Poor wound dressing techniques and unhygienic conditions may increase the risk for wound infection.
An infected wound may be characterized by increased or sustained pain, redness or swelling, pus discharge, bad odor or non-healing of the wound.
Infected wounds can have serious local and systemic complications. The most serious local complication of infected wounds is a non-healing wound, which results in significant pain and discomfort for the patient. The infection can also affect the surrounding tissues and may cause a bacterial skin infection (cellulitis) or an acute or chronic bacterial bone infection (osteomyelitis). If the infection spreads to the blood vessels, the bacteria may spread and cause infection in other areas of the body.
The primary factor that needs to be addressed in wound infections is proper wound care. A wound requires a moist (not wet) environment for proper functioning of the cells responsible for wound healing. It is recommended that dressings should be changed daily (or more often), and that proper precautions (washing hands prior to dressing the wound, sterilized equipment, etc.) during wound dressing be taken in order to minimize the risk of further infection. A number of advanced dressings, which are currently available, require less frequent dressing changes and may provide the added benefit of faster wound healing.
The use of antibiotics, whether applied directly to the wound (topical) or taken orally (systemic), should only be given under the direction of a physician. In some cases of severe infection, intravenous antibiotics may be given to combat severe blood infection (sepsis).