Pressure ulcer- Definition, Clinical features, and Stages

Pressure ulcer

Definition

• A pressure ulcer is a wound caused by unrelieved pressure to the dermis and underlying vascular structures usually between the Bone and support surface.

• When pressure is not relieved in time then the damage is cannot repair and recover on their own.

• The superficial dermis can tolerate ischemia for 2 to 8 hours before breakdown occurs.

• Deeper muscle connective tissue and fat tissues tolerate pressure for two hours or less.

• Thus, there may be significant damage to underlying tissues while the epidermis and dermis remain intact.

• Pressure ulcers occur most frequently in immobilized patients for a long period of time.

  

  Fig. 1: Pressure sore/ulcer
  

  
  

Clinical presentation

• The first clinical sign of pressure ulceration is blanchable erythema along with increased skin temperature.

• Progression to a superficial abrasion, blister, crater indicates the involvement of the dermis.

• When full-thickness skin loss is apparent the ulcer appears as a deep crater. Bleeding is minimal and tissue is indurated and warm.

• The majority of all pressure ulcers develop over six primary bony areas: sacrum, coccyx, greater trochanteric, ischial tuberosity,  calcaneus, and lateral malleolus (Fig. 2).

  

  Fig. 2: Common sites of pressure sores

  
  

Staging of pressure ulcer

Pressure ulcers are classified using a staging or grading system that gives information about tissue destruction.

Table 1: Staging of Pressure Ulcer
Pressure ulcer stage	Definition
Stage 1	Intact skin with non-blanchable erythema
Stage 2	Partial-thickness skin loss of dermis with erythema
Stage 3	Full-thickness tissue loss. Subcutaneous fat may be visible but bone, tendon, and muscles are not exposed.
Stage 4	Full-thickness tissue loss with exposed bone, tendon, or muscle.
Unstageable pressure ulcer	Full-thickness tissue loss in which the base of the ulcer is covered by slough, or eschar.