Pressure Ulcer Staging and Care
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Direct answer
A pressure ulcer is injury to skin or underlying tissue caused by sustained pressure, often with shear, over a bony prominence. The NPUAP staging system grades it from stage I, non-blanchable erythema, through stage II partial-thickness loss and stage III full-thickness loss to stage IV exposure of bone, tendon or muscle. Management rests on offloading, nutrition and moist wound care, with repositioning about every two hours in bed-bound patients.
What you must remember
- Stage I: non-blanchable erythema of intact skin, where warmth, oedema or firmness may replace redness in darker skin.
- Stage II: partial-thickness loss with a shallow open ulcer or blister and a pink wound bed, without slough.
- Stage III: full-thickness loss with visible fat and possible slough or eschar, but no exposed bone, tendon or muscle.
- Stage IV: full-thickness loss exposing fascia, muscle, tendon, ligament, cartilage or bone, with a high risk of osteomyelitis.
- Unstageable and deep tissue: unstageable when slough or eschar hides the base, while deep tissue injury is persistent non-blanchable maroon or purple discolouration.
- Risk factors: immobility, incontinence, malnutrition, sensory loss and shear from sliding in bed.
- Risk tool: the Braden scale quantifies risk, and a score of 18 or less identifies patients at risk.
- Offloading: regular repositioning, pressure-redistributing surfaces and avoiding massage over reddened bony prominences.
Staging and managing a sacral ulcer
A 60-year-old bedridden man with a spinal cord injury develops a sacral area that stays red when pressed, with intact skin. Two days later the skin has opened into a shallow pink bed.
- Stage by the deepest visible tissue: grade the lesion on what can be seen, because the stage depends on the depth at the base of the wound.
- Debride to reveal the base: remove slough or eschar where safe (stable dry heel eschar is left intact), because a hidden base leaves the wound unstageable until it is cleared.
- Offload immediately: reposition every two hours in bed-bound patients and use a pressure-redistributing mattress, since pressure relief is the core treatment.
- Optimise nutrition: a dietitian review, with adequate protein and energy, supports tissue repair, and anaemia and infection need correction.
- Dress the wound: moist dressings suit a clean pink bed, whereas infected or necrotic wounds need debridement and antibiotics guided by culture.
- Monitor and escalate: measure size and depth weekly, and refer deep wounds with exposed bone for surgical review and osteomyelitis assessment.
Where the exam tries to catch you
Three traps recur in staging questions.
- Trap: massaging a red, non-blanching area over the sacrum to improve circulation. Correct: massage over a bony prominence damages deeper tissue, so the area should be offloaded instead.
- Trap: calling a dark, boggy, purple area stage I. Correct: persistent maroon or purple discolouration is deep tissue injury, which can progress rapidly to a deeper ulcer.
- Trap: staging a wound covered by black eschar as stage III by default. Correct: the wound is unstageable until the base is visible.
Frequently asked questions
What distinguishes stage I from stage II pressure ulcer?
Stage I is non-blanchable erythema of intact skin, while stage II shows partial-thickness loss of the epidermis or dermis. A stage II pressure ulcer appears as a shallow open ulcer or blister with a pink wound bed and no slough.
What is an unstageable pressure ulcer?
An unstageable pressure ulcer is one whose true depth cannot be judged because slough or eschar covers the wound base. It is staged once the base is clear, so the classification remains provisional until debridement reveals the tissue below.
What is a deep tissue pressure injury?
A deep tissue pressure injury is persistent non-blanchable maroon or purple discolouration of intact skin, caused by damage to underlying tissue. It can evolve rapidly into a deeper ulcer, so it needs urgent offloading despite the skin looking intact.
Which score is used to assess pressure ulcer risk?
The Braden scale is the commonly used risk tool for pressure ulcers, and a score of 18 or less identifies patients at risk. It assesses sensory perception, moisture, activity, mobility, nutrition and friction or shear.