Pathophysiology & Risk Factors - Under Pressure
- Primary Injury: Sustained pressure on soft tissue, typically over a bony prominence, exceeds capillary filling pressure (>32 mmHg).
- Ischemic Cascade:
- Obstructed blood flow → ↓ tissue perfusion (ischemia) & lymphatic drainage.
- Waste product accumulation → inflammation, endothelial damage, thrombosis.
- Leads to irreversible tissue necrosis.
- Key Risk Factors:
- Immobility: sedation, paralysis, fractures.
- Sensory Loss: spinal cord injury, neuropathy.
- Extrinsic Factors: ↑ moisture (incontinence), friction, shear forces.
- Systemic Factors: poor nutrition (↓ albumin), anemia, altered mental status.
⭐ Shear forces, which stretch and distort tissue and vessels parallel to the skin, are more damaging than direct vertical pressure.

Pressure Ulcer Staging - Setting the Stage

| Stage | Depth of Tissue Loss | Clinical Presentation |
|---|---|---|
| Stage 1 | - | Intact skin with non-blanchable erythema. |
| Stage 2 | Partial-thickness | Shallow open ulcer with a red-pink wound bed, without slough. May also present as an intact or ruptured serum-filled blister. > ⭐ Exam favorite: Often mistaken for simple abrasion or tape burn. |
| Stage 3 | Full-thickness skin loss | Subcutaneous fat may be visible, but bone, tendon, or muscle are NOT exposed. Slough may be present. |
| Stage 4 | Full-thickness tissue loss | Exposed bone, tendon, or muscle. Slough or eschar may be present. Often includes undermining and tunneling. |
| Unstageable | Full-thickness tissue loss | Base of the ulcer is completely obscured by slough (yellow, tan, gray, green, or brown) and/or eschar (tan, brown, or black). |
| Deep Tissue Injury (DTI) | - | Purple or maroon localized area of discolored intact skin or blood-filled blister. |
Management by Stage - Healing the Hurt
- Core Principles: Offload pressure, optimize nutrition (protein, vitamins), manage incontinence, and maintain a moist wound environment.

- Stage 1: Intact skin. Focus on aggressive pressure relief and protective dressings.
- Stage 2: Partial-thickness loss.
⭐ Hydrocolloid dressings are often favored as they are impermeable to bacteria, provide a moist environment, and promote autolytic debridement.
- Stage 3 & 4: Full-thickness loss. Requires debridement of necrotic tissue. Surgical consultation for advanced wounds.
- Unstageable: Obscured full-thickness loss. Must be debrided to determine true depth.
Prevention Strategies - Stop the Sore
- Risk Assessment: Regularly use the Braden scale to identify at-risk patients (score <18 indicates high risk).
- Repositioning & Offloading: Key to prevention.
- Turn bed-bound patients at least every 2 hours.
- Shift weight for chair-bound patients every 15-30 minutes.
⭐ Bed-bound patients should be repositioned at least every 2 hours, while chair-bound patients require more frequent shifts, every 15-30 minutes, to effectively offload pressure from ischial tuberosities.
- Support Surfaces: Use pressure-reducing devices.
- Examples: High-specification foam mattresses, alternating pressure air mattresses, or low-air-loss surfaces.
- Skin Care:
- Keep skin clean, dry, and moisturized.
- Apply barrier creams to protect from incontinence.
- Nutrition:
- Optimize protein and calorie intake to maintain tissue health.
High‑Yield Points - ⚡ Biggest Takeaways
- Pressure redistribution (e.g., q2h turning) is the single most important step in prevention and management.
- Stage 1 is intact skin with non-blanchable redness; Stage 2 is partial-thickness loss of dermis.
- Stage 3 is full-thickness loss into subcutaneous fat; Stage 4 involves exposed bone, tendon, or muscle.
- Unstageable ulcers have a bed obscured by slough/eschar and require debridement (except stable heel eschar).
- Deep Tissue Injury is a localized area of purple or maroon discolored intact skin.
- Management requires a moist wound environment, adequate nutrition, and continuous pressure offloading.
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