Managing wound infection requires a holistic process, from assessment strategies to determine the level and severity of bacteria present, to identifying and understanding a patient’s particular risk factors. This requires a team approach, bringing together clinicians with specific expertise, including certified wound ostomy and continence nurses (CWOCNs).
With wound treatment, it is important to understand that while bacteria and bacterial byproducts can disturb the normal orderly process of wound healing, the presence of microorganisms alone may not be a risk factor for infection. Low levels of bacteria can colonize a wound without injury to the host. In fact, the presence of low levels of bacteria can actually enhance some processes such as fibroplasia. (Robson, 1997) Bacteria may even aid in desloughing and stimulate inflammation. (Tonge, 1997)
Bacteria balance can be plotted along a continuum, from lowest level to a more severe state of infection. The type and level of bacterial presence should be taken into consideration when determining treatment.
The lowest level on the bacterial balance continuum is “contaminated.” A small number of non-adherent, non-replicating bacteria is present, but do not negatively impact healing. The next level is “colonized,” at which bacteria are replicating in colonies and adhere to the surface. The bacteria are non-invasive, however, and wounds heal.
A more severe level is “critically colonized.” Here bacteria replicate and begin to invade the wound. Subtle signs of infection can be detected, and healing is delayed. The most serious level is “infected.” Bacteria replicate and are deeply invasive. Classic signs and symptoms of infection can be identified. Wound infection occurs when the number of organisms exceeds the ability of local tissue defenses to handle them. (Peacock and Van Winkel, 1976)
When treating infection, the determining factors are not just the number of bacteria and the virulence of the organisms. Clinicians need to consider the patient, as well as the wound. Risk of infection typically increases with a large wound area, increased wound depth, degree of chronicity, anatomic location (e.g., distal extremity or perineal), presence of a foreign body, necrotic tissue, and reduced perfusion. In addition there are systemic factors in the patient that create a higher risk of infection in chronic wounds, such as vascular disease, edema, malnutrition, diabetes mellitus, alcoholism, prior surgery or radiation, use of corticosteroids or other drugs, and inherited immune defects.
