Introduction

• A decubital ulcer can be defined as a localized injury to the skin or underlying tissue, usually over a bony prominence, as a result of unrelieved pressure.
• Cause: a large amount of pressure over a short period of time, or a small amount of pressure over a prolonged time typically in recumbent patients. Ischemia and reperfusion injury is thought to be involved in the pathophysiology.
• Signs: can vary in severity from patches of discolored or hyperemic skin to open wounds with or without exposure of underlying muscle and/or bony tissues. 
• Diagnosis: visual examination.
• Treatment: supportive/physical therapy.
• Prognosis: dependent upon the grade of the ulcer and response to treatment and ability to treat underlying cause of recumbency.

Pathogenesis

Etiology

• Sustained pressure of skin over bony prominence causing interruption of blood supply to a specific area resulting in progressive and potentially chronic ischemia.
• Pressure inhibits oxygenation and nutrition to the tissues.
• Ischemia and reperfusion causes further injury as the reperfusion leads to reactive oxygen species and cellular edema.

Intrinsic risk factors

• Mobility problems due to orthopedic, neurologic or systemic diesase.
• Poor nutritional or general health status.
• Concurrent health issues (circulatory compromise), eg diabetes mellitus, renal disease or cardiac disease.
• Geriatric life stage: aging skin, loss of elasticity and loss of body fat and muscle tone.
• Urinary and/or fecal incontinence; increased moisture on skin.
• Abnormal sensation which can occur with spinal injury or other neurological disease.

Extrinsic risk factors

• Pressure from hard or abrasive surfaces.
• Poor nursing care including lack of frequent position changes.
• Accumulation of moisture related to urine or fecal scalding or wound exudate.

Predisposing factors

General

• Patients vulnerable to decubital ulcers include:
  • Recumbent patients.
  • Patients with reduced ability or inability to adjust their position.
  • Debilitated or paralyzed dogs.
  • Patients with concurrent health conditions resulting in compromised circulation.
  • Larger dogs due to greater body weight.
  • Areas of body with reduced coverage of body fat.
  • Areas in direct contact with a supporting surface.

Timecourse

• The exact timecourse is difficult to determine as pressure ulcers may occur secondary to repetitive or prolonged pressure.

Diagnosis

Treatment

Outcomes