8.2 Pressure Injury Prevention & Staging Classification
Key Takeaways
Pressure and shear can injure tissue; no single pressure or elapsed-time threshold predicts injury for every resident.
Follow the individualized repositioning, seating, moisture-control, and support-surface plan and report intolerance or missed care promptly.
Float heels and use prescribed positioning devices as directed; never massage a reddened prominence or improvise a ring cushion.
Persistent color, temperature, firmness, or pain changes can indicate injury, including when redness is hard to see in darker skin.
NPIAP stages describe tissue loss; the nurse assesses and stages, while the aide observes, protects, and reports.
8.2 Pressure Injury Prevention & Staging Classification
Preserving integumentary integrity is a vital responsibility of the certified nursing assistant. Pressure injuries—formerly called decubitus ulcers or bedsores—are localized injuries to the skin and underlying tissue, typically over bony prominences. They cause severe pain, risk systemic infection, and represent serious complications of immobility. Because CNAs perform daily hygiene, dressing, and repositioning, they stand on the frontline of pressure injury prevention and early observation and reporting.
Pathogenesis and Etiology of Pressure Injuries
Pressure injuries result from intense or prolonged pressure, often combined with shear. Tissue deformation and impaired blood flow can damage skin and deeper tissue. There is no universal 32-mm-Hg threshold or two-hour point at which every resident's tissue dies. Damage depends on pressure, duration, perfusion, tissue tolerance, moisture, temperature, and support surfaces.
A resident who cannot feel discomfort or shift weight may develop damage before obvious skin changes appear. A mattress alone does not replace an individualized prevention plan. CNAs observe vulnerable areas during care, implement assigned repositioning/offloading, and report changes promptly. Nurses assess and stage injuries; aides should describe color, skin integrity, temperature, firmness, pain, and location rather than independently diagnosing a stage.
Extrinsic and Intrinsic Risk Factors
Pressure injury risk stems from mechanical forces interacting with host vulnerabilities:
Extrinsic Mechanical Forces
- Pressure: Perpendicular compressive force crushing soft tissue against a mattress or chair.
- Shearing Force: A parallel force created when tissue layers slide across one another. For example, when the head of the bed is elevated above 30 degrees, gravity drags the skeleton downward while the skin sticks to the bed linen. Deep fascial blood vessels stretch, twist, kink, and rupture, causing severe deep tissue damage.
- Friction: Mechanical rubbing of the skin surface across linens or equipment, scraping off the epidermal layer ("sheet burns").
- Moisture and Maceration: Exposure to urine, feces, sweat, or wound drainage macerates (softens) the epidermis, eroding the protective acid mantle and accelerating breakdown.
Intrinsic Risk Factors
- Immobility and Inactivity: Inability to feel pressure discomfort or shift weight independently.
- Malnutrition and Dehydration: Hypoalbuminemia impairs tissue repair; loss of subcutaneous fat eliminates natural cushioning.
- Advanced Age: Aging skin exhibits epidermal thinning, reduced dermal vascularity, and loss of elasticity.
- Sensory Neuropathy: Conditions like diabetes or stroke diminish protective sensation.
Anatomical Bony Prominences & The Braden Scale
Pressure injuries cluster over bony prominences where bone lies close to the skin with minimal muscle padding:
- Supine: Occiput, scapulae, spinous processes, elbows, sacrum, coccyx, and calcaneus (heels).
- Lateral (Side-Lying): Ears, acromion processes, ribs, greater trochanters, knees, and malleoli (ankles).
- Prone: Forehead, sternum, anterior iliac spines, patellae, and dorsal toes.
- Sitting / Wheelchair: Ischial tuberosities (bearing the greatest seated pressure), sacrum, and heels.
Nurses assess pressure risk using the Braden Scale, which evaluates six subscales: Sensory Perception, Moisture, Activity, Mobility, Nutrition, and Friction/Shear. Scores range from 6 to 23; scores of 18 or lower denote clinical risk, with lower scores indicating higher vulnerability.
Pressure Injury Prevention Protocols
Preventing tissue breakdown requires strict adherence to evidence-based protocols:
- Repositioning Schedules: Use the nurse-established schedule based on skin/tissue response, mobility, support surface, comfort, and care goals. A two-hour bed schedule may be ordered but is not universal. Follow the seating plan, encourage permitted weight shifts, and report pain, persistent discoloration, or inability to complete repositioning. Never wait for the next scheduled turn when distress is evident.
- 30-Degree Lateral Oblique Tilt: Avoid placing residents directly on the greater trochanter at 90 degrees. Instead, tilt the resident at a 30-degree angle, placing pillows behind the back and between knees to distribute weight over the fleshy buttocks.
- Floating the Heels: The calcaneus has minimal subcutaneous fat and breaks down rapidly. Float heels completely off the mattress by placing pillows lengthwise under the calves (lower legs). Ensure heels hang suspended in air without touching sheets. Never place pillows directly under heels or knees.
- Head of Bed (HOB) at 30 Degrees or Lower: Use the lowest elevation compatible with breathing, feeding, and other clinical needs. Do not lower a resident's bed contrary to aspiration or respiratory orders; ask the nurse to reconcile competing risks.
- Barrier Creams & Moisture Control: Cleanse perineal skin promptly after incontinence with pH-balanced cleanser. Pat dry gently—never scrub—and apply zinc oxide or dimethicone barrier cream.
- Support Surfaces: Use pressure-relieving foam or alternating air mattresses. Donut-shaped ring cushions are strictly prohibited because they constrict blood flow and worsen ischemia.
- The Massage Prohibition: Never massage reddened bony prominences. Rubbing ischemic tissue ruptures fragile capillaries and accelerates deep necrosis.
NPIAP Staging Classification System
The National Pressure Injury Advisory Panel (NPIAP) classifies pressure injuries by the anatomical depth of tissue loss:
| NPIAP Stage | Anatomical Tissue Depth & Visual Appearance | Clinical Hallmarks & Distinguishing Features | Common Sites |
|---|---|---|---|
| Stage 1 | Intact skin with localized non-blanchable erythema (redness that does not whiten under light pressure) | Redness may be difficult to see in darker skin; assess persistent color, temperature, firmness and sensation changes. Purple/maroon change raises concern for deep tissue injury, not Stage 1 | Sacrum, heels, trochanter |
| Stage 2 | Partial-thickness skin loss with exposed dermis | Viable, pink or red, moist wound bed; shallow open ulcer; or intact/ruptured serum-filled blister; no adipose visible | Ischium, coccyx, buttocks |
| Stage 3 | Full-thickness skin loss | Subcutaneous adipose (fat) tissue is visible; granulation tissue and rolled edges (epibole) often present; slough/eschar may be seen | Sacrum, greater trochanter |
| Stage 4 | Full-thickness skin and tissue loss | Directly visible or palpable fascia, muscle, tendon, ligament, cartilage, or bone; undermining and tunneling common | Sacrum, heels, ischium |
| Unstageable | Full-thickness skin and tissue loss with depth obscured | Slough/eschar obscures the extent of tissue loss; the clinician determines management. Do not remove stable, dry heel eschar or ischemic-limb eschar independently | Sacrum, heels, buttocks |
| Deep Tissue (DTPI) | Intact or non-intact skin with localized, persistent non-blanchable deep red, maroon, or purple discoloration | Caused by pressure/shear at bone-muscle interface; blood-filled blister or dark wound bed; can rapidly evolve | Calcaneus (heels), sacrum |
Sources checked October 16, 2026
IDDSI food and drink framework; Pressure injury prevention; NPIAP staging.
While performing morning perineal care and repositioning a bedbound resident, a certified nursing assistant observes a 3-centimeter area of persistent, dark redness over the resident's sacrum. When the CNA applies gentle fingertip pressure, the redness does not whiten or blanch. What action must the CNA take?
Vigorously massage the reddened area with moisturizing lotion to stimulate localized blood flow and promote capillary refill
Apply an electric heating pad set to medium directly over the sacrum to dilate constricted arterioles
Place a rubber donut ring cushion underneath the resident's buttocks to elevate the sacrum off the bed sheets
Avoid massaging the area, reposition the resident off their sacrum using a 30-degree tilt, and immediately report the non-blanchable erythema to the nurse
The nurse has identified pressure as the cause of a shallow wound with exposed pink dermis and no slough, fat, or deeper tissue. Which NPIAP stage is being described?
Stage 2 Pressure Injury
Stage 1 Pressure Injury
Stage 3 Pressure Injury
Deep Tissue Pressure Injury
The nurse explains a pressure injury has visible subcutaneous fat but no exposed or directly palpable fascia, muscle, tendon, cartilage, or bone. Which NPIAP stage is described?
Stage 1 Pressure Injury
Stage 3 Pressure Injury
Stage 4 Pressure Injury
Unstageable Pressure Injury
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