The Diabetic Foot: An Overview
by Lydia A Meyers RN, MSN, CWCN
Diabetes is the number one cause of amputation for wound care patients. Individuals with diabetes need monitoring and education about the dangers they face on a daily basis due to their condition. Diabetic ulcers often begin with a simple bump, as a callous or by stepping on something.
Infection is the major reason for amputation among diabetic patients. The wound allows bacteria to enter the system, and since individuals with diabetes have compromised immune systems, there is an increased chance of infection and sepsis. This can lead first to the amputation of toes and then limbs.
It is of the utmost importance that diabetic patients are properly monitored and made aware of the dangers that come with their condition. By decreasing the rate of amputations and improving quality of life through education and monitoring, fewer dollars will be spent on the long-term care of the patient with diabetes.
Diabetic wounds typically form due to trauma, ill-fitting shoes, or deformed feet. Individuals with diabetes need to be taught to do the following:
- Avoid walking without shoes
- Never cut their own toe nails
- Check their feet daily
- Have shoes that fit properly
- Regularly see a podiatrist
These preventative practices will help to decrease the incidence of wounds and subsequent amputations.
Those with diabetes often develop neuropathy which compromises the sensation in their feet and legs. At first, these individuals may suffer from a great amount of pain in their lower legs. The pain may be described as a burning, stinging, stabbing, or shooting sensation. If the individual complains about pain that becomes excessive, there could be an infection or acute Charcot foot. Charcot foot is caused by muscle weakness and displacement of bones caused by misshapen feet, which increases the incidence of pressure and calluses.
The loss in sensation due to neuropathy can hamper the ability of the individual to protect themselves from harm. The individual may not know when they're stepping on a sharp object, when shoes are not fitted properly or how hard they bump into objects due to this sensory loss. The assessment of individuals experiencing neuropathy includes use of a vibration perception threshold meter, the Semmes-Weinstein monofilament test or a tuning fork. To develop a full picture of the individual, an assessment needs to include both arterial studies and sensation studies.
Skin and Nail Health
The next assessment is the evaluation of skin and nails. This involves evaluation of further injury from cracks, maceration or fissures in the skin. A callous that has changed color or is bleeding is a sign of pre-ulcerative lesions. The nail beds and ingrown toenails are indicative of decreased circulation. With decreased circulation, there is an increased chance of cellulitis, osteomyletis, and amputation. An individual with diabetes that has had one amputation has an increased risk of successive amputations.
The assessment of infection may be difficult since individuals often do not have a fever or any of the outer signs of infection. Hyperglycemia impairs the symptoms of infection by inhibiting leukocyte production and the inflammatory response. A major indication of infection is an increase in blood sugars and a decrease in energy levels. One conclusive way to assure proper infection diagnosis is to have tissue cultures performed when a wound is showing a lack of progression.
A typical diabetic foot wound and patient assessment might go as follows: A patient presents with a fluid filled blister, reddened area at top of foot and increased amount of pain. The patient is admitted to ICU for evaluation and a wound consultant comes in. The nurses look at the feet and assess the fluid filled area. A surgery consult is put in and the patient is seen immediately. The surgeon, a wound care physician, identifies the fluid filled area as diabetic bullae. These bullae can indicate a necrotizing infection. The physician begins the fight to save the patient's foot. The toxins from the bacteria are present with each progressive wound cleaning and debridement.
If the wound does not continue to progress to healing, the patient would be a good candidate for hyperbaric oxygen therapy (HBOT). HBOT is responsible for saving many diabetic patients from amputation. For patients that do not have good arterial function, HBOT offers a chance to improve circulation and promote healing.
Nutritional support is important and difficult for the patient with diabetes. Uncontrolled HBA1C levels will often impede wound healing in diabetic foot wounds, more so than in pressure ulcers. The American Diabetes Association (ADA) does not endorse any special diet at this time. It is better to teach patients the type of foods to eat than to prescribe a specific diet for them to follow.
The diabetic foot wound offers a challenge to both the individual and the wound care specialist. It is important to prioritize the assessment and knowledge of infection signs and symptoms. Continued education is necessary to assure that the patient is aware of the hazards of not taking care of their feet or blood sugar levels. A diabetic patient needs to be aware of the challenges he/she can face from foot wounds that do not heal and amputation from uncontrolled infections. Knowledge of the many different types of wounds and threats that these patients face is important and should never be overlooked. It is better to be overly cautious with diabetic patients than to overlook something that would have been a major threat.
About the Author
Lydia Meyers RN, MSN, CWCN has been a certified wound care nurse for over 15 years with experience working in home healthcare, extended care facilities, hospice care, acute care, LTAC, and wound clinics. Her nursing philosophy to "heal wounds as quickly as possible" is the guiding force behind her educational pursuits, both as a teacher and a student.
The views and opinions expressed in this blog are solely those of the author, and do not represent the views of WoundSource, Kestrel Health Information, Inc., its affiliates, or subsidiary companies.