Chapter I Introduction to Diabetes Mellitus

Chapter II Diabetes Mellitus

Chapter III Laboratory Tests and Monitoring

Chapter IV Insulin and Oral Antidiabetic Agents

Chapter V The Diabetic Diet

Chapter VI Diabetic Foot and Wound Conditions and Treatment

Chapter VII Complications of Diabetes Mellitus

Chapter VIII The Family and Diabetes

Chapter IX Coping With Diabetes

References

Post Examination

Chapter VI      Diabetic Foot and Wound Conditions and Treatment

FOOT AND WOUND PROBLEMS

Foot infections are a major case of hospitalizations in the diabetic population.  Approximately 20% of all admissions are the result of foot problems, which can become limb, and life-threatening.

It is important to remember that once a problem develops appropriate diagnosis and treatment is essential if the foot is to be returned to full function.  Without appropriate treatment, chronic problems can be created, which can eventually lead to amputation.

PERIPHERAL VASCULAR DISEASE

In the lower extremity, diabetes affects the vascular and nervous systems.  The large arteries in the lower leg can become calcified or clogged while the capillaries become thickened, decreasing the ability for oxygen and nutrients to pass into the surrounding tissue and skin, therefore causing injuries to heal poorly.  Poor circulation can also lead to swelling and dryness of the foot.  With decreased blood flow, necrosis can develop, which interferes with the body’s ability to fight infection.  This inability can develop into a rapidly spreading cellulitis or take the form of localized pockets under the skin or abscesses.  Although infection is usually not the direct cause of an ulceration or wound, it does have great importance in the outcome.  If neglected or improperly treated, ulcers may become infected due to prolonged exposure to the external environment or to excessive weight bearing.  While these conditions are associated with long standing problems, small scrapes or cracks in the skin may lead to severe infections when inadequate blood flow is present.

Since infection is the number one predisposing factor in lower extremity amputation, it is essential that the patient and health care team take an aggressive approach in the prevention and management of infections.  In the diabetic patient, foot infection is the result of several factors, which include neuropathy, vascular disease, and decreased resistance to infection.  If trauma is added to the equation, the diabetic foot is at risk for ulceration and infection.  Not all foot infections are the result of bacterial invasions, but these sequences of events are the most common leading to lower extremity sepsis.

Immunopathy and defects in leukocyte function are associated with diabetic’s susceptibility to infection.  Leukocyte phagocytosis, with impaired intracellular killing of bacteria, is significantly reduced in patients with poorly controlled diabetes.

Diabetic foot infections are polymicrobial in nature.  These wounds contain anaerobic bacteria along with a wide spectrum of aerobic organisms.  Three to five different organisms can usually be cultured from moderate to severe infections.  The most common organisms are the aerobic gram-positive cocci, including staphylococcus aureus, coagulase negative staphylococci, and group B streptococci.  Aerobic gram-negative pathogens frequently cultured are proteus.

Anaerobic organisms can be found in 80% of patients with moderate or severe infections.  Gram-negative rods especially bacteroids, are extremely pathogenic and can cause septicemia in advanced diabetic foot infections.              

NEUROPATHY

Over 50% of diabetics can be affected by a condition called neuropathy.  High glucose levels can damage nerves resulting in abnormal or decreased sensation.  A sign of neuropathy is the early stages includes a burning pain on the bottom of the feet..  As neuropathy progresses, numbness starting at the toes and progressing to the foot, the inability to feel pain or hot or cold temperatures develops.  This protective mechanism can be decreased to the extent that minor cuts, scrapes, blisters, and abnormal spots may develop, leading to severe infection.

In the absence of pain, a pressure spot can develop into a thick callus.  With the breakdown of the underlying skin regions, mal-perforant ulcers develop.  Such wounds should be treated as an emergency and medical attention should be obtained within 24 hours once an ulcer or bleeding within the skin occurs.

Charocot arthropathies are micro-fractures that are a result from the loss of sensation.  The foot becomes red, swollen and deformed with minimal or no pain.  If not treated the foot can become deformed, making it difficult to walk or wear shoes.

Foot Care and Diabetes

Nursing Implications

The diabetic patient should be continuously aware of any potential problem or existing problems concerning the feet.  Proper foot care is critical since diabetics are prone to foot problems.  Simple daily foot care and diabetes management can prevent these problems, and should be made a part of the daily routine.

  • Adequate management of diabetes

It is important to develop a life style that consists of healthy choices to maintain glucose levels as close to normal as possible.

  • Check feet daily

Feet should be checked daily for red spots, bruises, cuts, blisters, and dryness or cracks.  This should include checking between and under the toes and feeling for tenderness, hot spots or other signs of infection.

  • Wash feet daily

Feet should be washed in warm water with mild soap.  Before bathing, the water should be tested for temperature with the hand or elbow.  The feet should be dried well, especially between the toes.  Talcum powder may be used to keep the skin dry between the toes.

  • Keep the skin soft and smooth

Lanolin-based creams can be applied to dry skin, but not between the toes due to risk of infection.

  • Shoes and socks

Shoes and socks should be worn at all times.  Socks, stockings or nylons should be seamless and worn with shoes at all times to prevent the formation of blisters or sores.  Check shoes daily for foreign objects and to make sure the lining is smooth.  Shoes should fit well and protect the feet.

  • Trim toenails as needed

Trim toenails with clippers after they are washed and dried thoroughly.  Toenails are trimmed straight across and smoothed with an emery board.  If the nails are yellow or thick a podiatrist should be consulted.

  • Protect feet from hot and cold

Insulated boots should be worn to keep feet warm on cold days.  During warm days sunscreen can be used on the tops of the feet to protect them from the sun.

  • Exercise feet

Exercising regularly can help blood flow and increase flexibility.  Walking is the best overall conditioner for the feet.  Walking not only improves circulation, but also promotes good general health.

THINGS TO AVOID

  • Do not walk barefoot, even indoors.  This can expose the skin to cuts and foreign bodies.  Walking on hot sand can result in serious burns.
  • Do not use heating pads or hot water bottles on feet.  This may cause burns due to decreased sensation.
  • Do not wear shoes, socks or stockings that are tight or worn out.  This could cause pressure sores or decrease circulation.
  • Do not soak feet unless specifically ordered.  Soaking can dry out the skin and cause the skin to crack.
  • Do not trim calluses, corns or abnormally thick nails unless advised by a podiatrist.
  • Do not cross legs for long periods of time.
  • Do not rely on the absence of pain to determine if treatment is necessary.
  • Do not wear sandals or other open footwear.

ASSESSMENT OF THE DIABETIC FOOT WOUND

NURSING IMPLICATIONS

Location

Wounds on the medial aspect of the foot are caused by constant low pressure, as in wearing tight shoes.  Wounds on the plantar aspect of the foot are caused by repetitive moderate pressure.

Description of wounds

When describing the wound, terms such as granular, fibroid, or necrotic are used.  The size, presence or absence of drainage can be described as serous or purulent.  Further description of odor and color should be included.  Wounds with purulence and/or two of the following signs should be considered infected:

  • Erythema
  • Lymphangitis
  • Cellulitis
  • Loss of function
  • Edema
  • Pain
  • Fluctuant underneath the skin

Signs of Peripheral Vascular Disease (PVD)

  • Non-palpable pedal pulses
  • Pallor on elevation of limbs
  • Dusky color or appearance of toes
  • Lack of hair on digits and dorsum of foot
  • Atrophic shiny skin
  • Pain at rest alleviated with dangling the foot or walking

Next Chapter VII     Complications of Diabetes Mellitus