Pressure Injuries

A wound with visible bone at the base and one with an intact blister over a dark area are separated by multiple stages — but a wound covered in black eschar? You can't stage it at all.

Pressure injuries are staged by the deepest tissue layer visible, not by wound size or appearance of surrounding skin. Stage 1 is intact skin with non-blanchable erythema — press the area and the redness stays. In darker skin tones, look for color changes, temperature differences, or firmness rather than redness. Stage 2 involves partial-thickness skin loss presenting as a shallow open ulcer with a red-pink wound bed, or an intact or ruptured serum-filled blister. No slough or bruising is present. Stage 3 is full-thickness skin loss where subcutaneous fat may be visible, but bone, tendon, and muscle are NOT exposed. Undermining and tunneling may occur. Stage 4 is full-thickness tissue loss with exposed bone, tendon, or muscle. Deep tissue injury (DTI) presents as intact or non-intact skin with a localized area of persistent deep-red, maroon, or purple discoloration, or an epidermal separation revealing a dark wound bed or blood-filled blister. Unstageable injuries have a wound bed obscured by slough (yellow, tan, gray, green, or brown) or eschar (tan, brown, or black) — you cannot determine the stage until enough debris is removed to visualize the base. Critical rule: pressure injuries are never reverse-staged. A healing Stage 4 does not become a Stage 3. Document it as a 'healing Stage 4.'

Key Distinctions

Don't confuse Stage 2 (partial-thickness, no slough) with a moisture-associated skin injury — Stage 2 occurs over bony prominences, moisture damage follows skin folds and perineal areas. Students mistake DTI for Stage 1; DTI is deeper, darker (maroon/purple), and often evolves rapidly. Unstageable does not mean 'worst stage' — it means you literally cannot see what's underneath.

Clinical Pearl

If you can't see the bottom, you can't call the stage. Eschar and slough hide the truth — document it as unstageable until debridement reveals the wound bed.

Pressure Injury Prevention

Pressure injury prevention centers on eliminating or reducing sustained pressure, shear, friction, and moisture on vulnerable tissue. The foundation is structured repositioning: turn immobile patients every 2 hours in bed and offload weight every 15 minutes when seated in a chair. Use the 30-degree lateral position to keep the patient off the sacrum and greater trochanters — the two highest-risk sites. Risk assessment drives the plan. The Braden Scale (scored 6–23) is the standard tool; a score of 18 or below signals increased risk, and lower scores demand more aggressive interventions. Six subscales — sensory perception, moisture, activity, mobility, nutrition, and friction/shear — each identify a modifiable risk factor. Nutrition is a commonly underestimated driver: inadequate protein and caloric intake impairs tissue tolerance. Albumin below 3.5 g/dL and prealbumin below 15 mg/dL flag nutritional risk. Keep skin clean and dry, apply moisture barriers for incontinence, use pressure-redistribution surfaces (not "pressure-relieving" — nothing eliminates pressure entirely), float heels off the bed with pillows, and avoid elevating the head of bed above 30 degrees for prolonged periods to minimize sacral shear. Never massage reddened or bony prominences — this damages fragile capillaries.

Key Distinctions

Don't confuse pressure redistribution devices (spread pressure over a larger area) with positioning schedules (eliminate sustained pressure through turning) — the device does not replace repositioning. Students think a specialty mattress means they can skip the 2-hour turn; it doesn't. A Braden score is inversely scaled: lower number equals higher risk — the opposite of what most students assume on first encounter.

Clinical Pearl

Braden is backward — low score, high risk. Think of it like a bank account: the lower the number, the less reserve the skin has to withstand pressure.