This topic covers pressure injuries, chronic wounds (including diabetic foot ulcers), principles of wound care, acne, and pruritus. Related conditions are covered elsewhere: infections (Topic 84), immune-mediated disorders such as psoriasis, lupus skin care, contact dermatitis, and urticaria (Topic 85), and burns (Topic 87).

Pressure injury is localized damage to skin and underlying tissue, usually over a bony prominence (sacrum, heels, hips, ischium, occiput) or under a medical device. Sustained pressure, especially combined with shear, compresses capillaries → ischemia → cell death. Deep muscle is more vulnerable than skin, so damage can start deep and appear later on the surface.

Contributing factors: immobility, sensory loss, moisture (incontinence, sweat), friction and shear (sliding down in bed), poor nutrition and hydration, older age, low perfusion, and critical illness.

Diabetic foot ulcer results from neuropathy (loss of protective sensation, deformity, high-pressure areas), peripheral artery disease, and impaired healing; infection is often polymicrobial.

Wound healing phases: hemostasis → inflammation → proliferation (granulation, epithelialization) → remodeling (up to 1–2 years). Healing needs moisture balance, adequate blood flow, nutrition, and absence of infection and pressure.

Acne vulgaris: excess sebum, follicular plugging, Cutibacterium acnes, and inflammation → comedones, papules, pustules, nodules, scarring.

NPIAP pressure injury staging (definitions in current use)

The 2025 International Pressure Injury Guideline (4th edition, EPUAP/NPIAP/PPPIA) keeps this classification without substantive conceptual change.

Key rules: do not reverse-stage a healing wound (a healing stage 3 stays "healing stage 3"); Stage 2 is not used for skin tears, moisture-associated skin damage, or burns.

Wound assessment (document every time)

• Location, length × width × depth, undermining and tunneling (clock positions)
• Tissue type: granulation (red, beefy), slough (yellow), eschar (black), epithelial tissue
• Exudate amount and type, odor (after cleansing), wound edges, surrounding skin
• Signs of infection: increasing pain, warmth, erythema, purulent drainage, odor, delayed healing, fever
• Pain score

Diabetic foot ulcer: first assess and document size, depth, exudate, tissue, infection signs, pulses, sensation (monofilament), and whether bone can be probed.

Pressure injury treatment

• Remove pressure — support surfaces (pressure-redistributing mattresses), offloading
• Moist wound healing with dressings matched to the wound:

• Moist dressings promote autolytic debridement of necrotic tissue and epithelialization, reduce pain, and speed healing
• Debridement: autolytic, enzymatic, mechanical, sharp/surgical
• Surgical flap for selected stage 3–4 injuries

Diabetic foot ulcer: offloading (total contact cast or boot), debridement, infection treatment, revascularization if ischemic, glucose control.

Acne

• Topical: benzoyl peroxide, retinoids (tretinoin, adapalene), topical antibiotics (always with benzoyl peroxide to limit resistance)
• Oral: doxycycline or minocycline (limited duration), hormonal therapy for some women
• Isotretinoin for severe nodular or scarring acne

Pruritus: treat the cause; emollients, cool compresses, antihistamines as appropriate.

Drug safety

Listed in priority order.

1. Risk assessment — Braden Scale on admission, per policy, and with any change in condition; full skin inspection including under devices
2. Pressure redistribution
   • Reposition regularly on an individualized schedule (traditionally at least every 2 hours in bed); use a 30-degree lateral tilt
   • Keep head of bed at 30 degrees or lower when safe, to reduce shear
   • Float heels off the bed with pillows under the calves or heel-offloading boots
   • Use lifting devices and draw sheets — do not drag
   • Chair-bound clients: shift weight often; pressure-redistributing cushion; avoid ring (donut) cushions
   • Reposition and pad medical devices
3. Skin care
   • Do not massage reddened areas or bony prominences (worsens deep damage)
   • Manage incontinence promptly; pH-balanced cleanser; moisture barrier
   • Moisturize dry skin
4. Nutrition — adequate calories and protein (commonly 1.25–1.5 g/kg/day for adults with pressure injuries, if not contraindicated), fluids, dietitian referral
5. Wound care — cleanse with saline or a wound cleanser, apply the chosen dressing, protect surrounding skin, measure weekly, report deterioration
6. Pain — premedicate before dressing changes; non-drug measures
7. Itch management — short nails, cool compresses, avoid hot water, discourage scratching

• Change position frequently; use the recommended mattress or cushion; check skin daily (use a mirror or caregiver) for redness that does not fade
• Eat enough protein and drink fluids
• Diabetes foot care: inspect feet daily, never walk barefoot, wear well-fitting shoes, report any sore promptly
• Keep dressings clean and dry; report increasing pain, odor, redness, pus, or fever
• Isotretinoin: use required contraception, attend monthly visits, report mood changes, do not share the medication, avoid sun and use moisturizer and lip balm
• Acne: wash gently twice daily, do not pick or squeeze lesions, use non-comedogenic products; results from treatment take 6–8 weeks
• Itching (e.g., urticaria): avoid scratching; cool compresses help reduce itch and swelling; wear loose cotton clothing

• Braden Scale: 6 subscales; lower score = higher risk
• Stage 1 = intact skin, non-blanchable erythema; Stage 2 = partial thickness, exposed dermis or intact blister
• Stage 3 = fat visible; Stage 4 = bone, tendon, or muscle exposed
• Unstageable = base hidden by slough or eschar; do not remove stable heel eschar
• DTPI = persistent maroon or purple discoloration
• Never reverse-stage; do not massage red areas; no donut cushions
• Head of bed at or below 30 degrees; float heels; lift, don't drag
• Moist dressings support autolytic debridement and epithelialization; match dressing to exudate
• Diabetic foot ulcer: assess and document first, offload, check perfusion
• Isotretinoin: teratogenic — two forms of contraception, monthly pregnancy tests (iPLEDGE), mood monitoring
• Itch: cool compresses, no scratching