By Laurie Swezey RN, BSN, CWOCN, CWS, FACCWS

Diabetic foot ulcers are one of the most dreaded complications of diabetes, and represent a significant cause of morbidity and mortality. It is estimated that a lower limb is sacrificed every 30 seconds somewhere in the world due to diabetes, and that diabetes is the reason for almost 50% of non-traumatic amputations of the lower leg throughout the world. Considering these facts, proper management of diabetic foot ulcers is of paramount importance.

There are several risk factors for the development of diabetic foot ulcers, including peripheral vascular disease, edema, and calluses. A triad of symptoms most often associated with diabetic foot ulcers is comprised of: deformity, trauma, and sensory neuropathy of the feet or lower legs. This triad is thought to be responsible for up to 65% of all diabetic foot ulcers.

Successful management of diabetic foot ulcers hinges on addressing three treatment modalities: debridement, offloading, and infection management.

Debridement

Debridement is the removal of all nonviable tissue that may impede wound healing, including any foreign bodies, calluses, and dead (necrotic) tissue. Wounds must be debrided down to the level of viable tissue. Debridement may be performed using an instrument (sharp debridement) or by the use of autolytic agents or dressings. Mechanical debridement and surgical debridement are other options for removal of necrotic tissue. Regardless of the method chosen, debridement is needed to reduce the risk of infection and remove any obstacles to healing, such as increased periwound pressure.

Once the wound has been debrided, it should be covered with a dressing that will prevent drying of the wound bed, protect the wound from infection, and absorb excess wound fluid if necessary. There are numerous dressings on the market. It is important to choose the correct dressing, keeping the above goals in mind.

Offloading

Offloading refers to redirecting weight (or pressure) off and away from the wound. This can be achieved by having the patient use a wheelchair or crutches. Although these methods are highly effective, they may not be suitable or desirable for all clients. Total contact casts are another option to remove pressure from diabetic foot ulcers; however, they can be difficult to apply, as well as time-consuming. Clients who are morbidly obese, have very deep or infected wounds, or who have severely compromised circulation to the foot are poor candidates for total contact casts.

Removable cast walkers can also be used, but their effectiveness may be greatly reduced if clients are not compliant (i.e. do not wear the devices at all times when ambulating). The advantages of removable cast walkers are the ability to inspect the wound frequently and accessibility to change dressings at any time. They also make detection of wound infection easier. As mentioned, however, these advantages are negated if clients do not wear the devices as recommended.

Proper footwear that is specially made for the client (i.e. custom orthotics) can also be useful in offloading pressure from the affected foot.

Infection Control

Clinicians treating diabetic foot ulcers should maintain a high index of suspicion for wound infections, including silent infection. Signs of infection may include:

• Increased drainage from the wound
• Increased pain as reported by the client
• Increased redness/swelling of the periwound
• Foul odor of wound drainage that is still present after the wound has been cleansed

Systemic signs of infection may include fatigue, fever, tachycardia, and general malaise. When infection is suspected, cultures should be obtained. Antibiotics that are shown to be effective against the offending organism through sensitivity testing should be given either orally or intravenously, depending on the severity of the infection. Antimicrobial dressings may also be considered.

Given the potential for loss of limb accompanying diabetic foot ulcers, these wounds should be treated aggressively using all tools available. Debridement, offloading, and infection control are the mainstays of management of diabetic foot ulcers.

Sources
Kruse, I. & Edelman, S. (2006). Evaluation and treatment of diabetic foot ulcers. Clinical Diabetes April 2006 24: 91-93.

Doupis, J. & Veves, A. (2008). Classification, diagnosis, and treatment of diabetic foot ulcers. Wounds.

Myers, B. (2008). Wound Management: Principles and Practice (2nd edition). Pearson Prentice Hall. Upper Saddle River, New Jersey, p. 71-89.

About The Author
Laurie Swezey RN, BSN, CWOCN, CWS, FACCWS is a Certified Wound Therapist and enterostomal therapist, founder and president of WoundEducators.com, and advocate of incorporating digital and computer technology into the field of wound care.