Chapter 210. Ischemic Ulcer

A 58-year-old woman with uncontrolled type 2 diabetes, hypercholesterolemia, and tobacco use presented with a 2-month history of a nonhealing ulceration on her left foot (Figure 210-1). She believes this started after she stepped on a tack. She presented with the ulcer, loss of protective sensation, and a nonpalpable posterior tibial pulse. She began treatment in a wound care center. Arterial noninvasive studies showed severe vascular disease and she underwent revascularization. While in the hospital, she quit smoking and gained control of her diabetes. Her ulcer healed and she continues to take her diabetes medications and does not smoke.

Ulcerations occur from ongoing biomechanical forces or trauma and require normal blood flow to heal. Nonhealing ulcers are commonly a result of peripheral ischemia seen in patients with diabetes and other vascular diseases. Treatment includes local wound care and improvement or correction of underlying factors causing ischemia. Untreated ischemic ulcers become infected and may require amputation of the affected area.

Arterial ulcer.

Of patients with diabetes, 15% to 25% will develop an ulcer at an annual incidence of 1% to 4%.1

Microvascular dysfunction is an important component of the disease process that occurs in diabetic foot disease. The abnormalities observed in the endothelium in patients with diabetes are not well understood and evidence suggests that endothelial dysfunction could be involved in the pathogenesis of diabetic macroangiopathy and microangiopathy.2 Microangiopathy is a functional disease where neuropathy and autoregulation of capillaries lead to poor perfusion of the tissues, especially at the wound base.

• Diabetes for more than 10 years, especially with poor glycemic control and the presence of other macro- or microvascular complications.
• Peripheral vascular disease from any cause or other vascular risk factors, including dyslipidemia and tobacco use.
• Neuropathy caused by loss of protective sensation and as a sign of microvascular disease.
• History of a previous ischemic ulcer.

Clinical Features

• Pain.
• Gray/yellow fibrotic base (Figures 210-1 and 210-2).
• Undermined skin margins.
• Punched-out appearance.
• Nonpalpable pulses.
• Associated trophic skin changes (e.g., absent pedal hair and thin shiny skin).

Typical Distribution

• Distal aspect of the toes.

Imaging

• Noninvasive studies (e.g., arterial Doppler and pulse volume recordings) are important for baseline assessment of the patient's blood flow.3
• Radiographs may be necessary to rule out osteomyelitis.

• Neuropathic ulcer usually presents with beefy red wound base and hyperkeratosis at the skin margins (see Chapter 211, Neuropathic Ulcer).
• Infected wounds present with localized redness, edema, drainage, and warmness in any of the diabetic-type wounds with lack of systemic symptoms of infection.
• Gangrene usually is well-demarcated with black eschar in foot with vascular disease (see Chapter 213, Dry Gangrene).

• Consider vascular surgery consultation to evaluate for revascularization.
• Carefully evaluate for a concomitant infection. Antibiotics are not indicated unless infection is present.
• Avoid aggressive debridement until optimization of blood flow occurs.
• Change dressings twice daily to evaluate the wound and keep a low bacterial load. Many advanced therapies can be added to accomplish the same goals.
• If the wound is plantar, offloading is important to prevent the wound from increasing in size.

• In patients with diabetes, adequate glycemic control is essential. A yearly comprehensive foot examination should be performed.
• Smoking cessation.

Prognosis of an ischemic ulcer depends on the possibility of revascularization. Many ulcers treated early heal. Untreated or inadequately treated ulcers lead to infection and amputation. Early recognition of underlying vascular disease is imperative for a successful outcome.

• Schedule weekly to biweekly visits to monitor the ulcer.
• Obtain serial radiographs every 4 weeks to monitor for the development of osteomyelitis.
• Closely monitor the patient every 3 to 4 months once healing has occurred. Patients who have had history of ulcerations are 36 times more likely to develop another ulcer.5

• Prevention measures, such as smoking cessation, are important to aid wound healing.4
• Promote successful treatment by encouraging adherence with use of offloading devices.
• Strive for normal glycemic control to optimize outcome for healing and surgical intervention.