Wound care and pressure injuries

In short

Wound care is the nursing science of assessing a break in skin or tissue integrity, preparing the wound bed and selecting dressings so that healing proceeds with the least pain, infection and scarring. A pressure injury (pressure ulcer, bedsore, decubitus ulcer) is localised damage to skin and underlying soft tissue over a bony prominence or under a medical device, caused by sustained pressure or pressure with shear - and it is largely preventable, which is why it is treated as a nursing-sensitive quality indicator. In India it is examined in medical-surgical nursing papers (INC/NNMC-pattern B.Sc Nursing), in fundamentals of nursing, and in staff-nurse recruitment tests (AIIMS, PGIMER, JIPMER, NHM, ESIC, state PSC, DSSSB) where staging, Braden scoring and turning schedules are standard questions. Employers - corporate hospitals under NABH accreditation, government tertiary hospitals, home-care and ICU settings - audit pressure-injury incidence per 1,000 patient-days and expect every nurse to document a skin assessment on admission. Interviews test whether you can stage an ulcer correctly, justify a dressing, and recite prevention bundles.

Explained

Skin, wound types and classification

• Skin layers: epidermis (avascular, barrier), dermis (collagen, vessels, nerves, appendages), subcutaneous fat, then fascia, muscle, bone. Depth of tissue loss defines wound depth and healing potential.
• Acute vs chronic wound: an acute wound heals in an orderly, timely sequence; a chronic wound is stalled (conventionally >4-6 weeks) in the inflammatory phase - pressure, venous, arterial and diabetic foot ulcers.
• By cause: incised, lacerated, abrasion, puncture, penetrating, contusion, avulsion, degloving, burn, bite.
• By contamination: clean (elective, no viscus opened), clean-contaminated (controlled entry of GI/respiratory/GU tract), contaminated (fresh trauma, spillage), dirty/infected (old trauma, pus, perforated viscus). Drives antibiotic prophylaxis and expected infection rate.
• By thickness: partial-thickness (epidermis ± part of dermis, heals by epithelialisation, little scar) vs full-thickness (through dermis, heals by granulation, contraction and scar).
• Healing intention: primary (clean edges approximated - sutures, staples, glue; minimal scar); secondary (left open, fills with granulation tissue and contracts - abscess cavity, stage 3/4 pressure injury); tertiary / delayed primary (left open 3-5 days for drainage or oedema, then closed).

Phases of wound healing and what disturbs them

1. Haemostasis (immediate): vasoconstriction, platelet plug, fibrin clot; growth factors (PDGF, TGF-β) released.
2. Inflammatory phase (day 0 to ~4): vasodilation, neutrophils then macrophages debride the wound; clinical signs are redness, warmth, swelling, pain - expected, not automatically infection.
3. Proliferative phase (~day 4 to 21): fibroblasts lay type III collagen, angiogenesis forms red granulation tissue, myofibroblasts contract the wound, epithelial cells migrate from edges and appendages.
4. Maturation / remodelling (3 weeks to 1-2 years): collagen III replaced by stronger type I, scar pales and flattens; the healed wound regains only about 70-80% of original tensile strength.
5. Local factors delaying healing: pressure, shear, infection/biofilm, necrotic slough and eschar, dryness or excess exudate, foreign body, oedema, poor perfusion, repeated trauma from dressing removal.
6. Systemic factors: age, protein-energy malnutrition, anaemia, hypoxia, diabetes and hyperglycaemia, obesity, smoking, uraemia, jaundice, malignancy, corticosteroids, cytotoxic drugs, radiotherapy, immunosuppression, vitamin C and zinc deficiency.
7. Complications: haemorrhage, haematoma, infection and abscess, dehiscence (partial or total separation of layers - classically days 5-10, patient reports "something gave way", serosanguineous discharge), evisceration (viscera protrude - emergency: low Fowler's, cover with sterile saline-soaked gauze, nil by mouth, call surgeon, prepare for theatre), sinus or fistula, hypertrophic scar and keloid (extends beyond wound margin), contracture, malignant change (Marjolin ulcer).

Pressure injuries: aetiology, staging and sites

• Mechanism: sustained interface pressure above capillary closing pressure (roughly 32 mmHg) causes ischaemia, reperfusion injury and cell death; shear deforms and occludes vessels in deep tissue; friction abrades the surface; moisture (incontinence, sweat, exudate) macerates skin and raises the risk. Damage often begins at the bone-muscle interface and surfaces late - hence the "iceberg" effect.
• Pressure + time: high pressure for a short time or low pressure for a long time can both cause injury; muscle is more susceptible than skin.
• Current staging (NPIAP/EPUAP 2019 international guideline, "pressure injury" terminology):
  • Stage 1: intact skin with non-blanchable erythema; in dark skin tones look for a change in colour from surrounding skin, warmth, firmness, boggy or painful area.
  • Stage 2: partial-thickness loss of dermis - shallow open ulcer with pink-red moist bed, or an intact/ruptured serum-filled blister. No slough, no fat visible.
  • Stage 3: full-thickness loss - subcutaneous fat visible; slough or eschar may be present but does not obscure depth; undermining and tunnelling possible. No bone, tendon, muscle or fascia exposed.
  • Stage 4: full-thickness loss with exposed or directly palpable fascia, muscle, tendon, ligament, cartilage or bone; osteomyelitis risk.
  • Unstageable: base obscured by slough or eschar - stage only after debridement. Stable, dry, adherent eschar on an ischaemic heel is not debrided.
  • Deep tissue pressure injury (DTPI): intact or non-intact skin with persistent deep red, maroon or purple discolouration or a blood-filled blister; may resolve or evolve rapidly to stage 3/4.
  • Medical device-related pressure injury: conforms to the shape of the device (NIV mask, ET tube, nasogastric tube, cervical collar, pulse oximeter probe, cast, urinary catheter) - staged by the usual system.
  • Mucosal membrane pressure injury: mucosa under a device - cannot be staged.
• Common sites by position: supine - occiput, scapulae, elbows, sacrum, coccyx, heels; lateral - ear, acromion, greater trochanter, medial/lateral condyles, malleoli; prone - forehead, chin, chest, iliac crests, knees, toes; sitting - ischial tuberosities, sacrum, heels, popliteal area. Sacrum/coccyx, heels and ischium account for most injuries.
• Differential diagnosis: incontinence-associated dermatitis and other moisture-associated skin damage (diffuse, over perineum/skin folds, not over a bony point, no clear edge), skin tear, arterial ulcer (punched-out, painful, over toes/lateral malleolus, absent pulses), venous ulcer (medial malleolus, shallow, oedema, hyperpigmentation), diabetic foot ulcer (plantar pressure point, neuropathic, painless).

Risk assessment, prevention bundle and standards

• Braden scale (most used): six subscales - sensory perception, moisture, activity, mobility, nutrition, friction/shear. Score 6-23; lower = higher risk. Common cut-offs: 15-18 mild, 13-14 moderate, 10-12 high, ≤9 very high risk.
• Norton scale: 5 items (physical condition, mental state, activity, mobility, incontinence), score 5-20, ≤14 at risk. Waterlow score: build/BMI, continence, skin type, mobility, sex/age, appetite plus special risks; ≥10 at risk, ≥15 high, ≥20 very high. Gosnell and, for paediatrics, Braden Q.
• Timing: complete a structured risk assessment and head-to-toe skin inspection as soon as possible after admission (within 8 hours), then at each shift/daily for at-risk patients and on any change in condition. Document with photographs where policy permits and consent is taken.
• Prevention (SSKIN / bundle): Surface, Skin inspection, Keep moving, Incontinence and moisture, Nutrition.
  • Repositioning: individualised; conventionally 2-hourly in bed, hourly when seated (shift weight 15 seconds every 15 minutes if able). Use the 30° lateral tilt; avoid 90° side-lying and sliding down.
  • Keep head of bed ≤30° unless contraindicated (reduces sacral shear); use the 30° semi-Fowler's rather than high Fowler's for long periods.
  • Offload heels completely with a pillow under the calf or a heel-suspension boot, knee slightly flexed.
  • Support surfaces: high-specification reactive foam mattress for all at-risk patients; alternating-pressure or low-air-loss surfaces for high risk or existing injury. A support surface does not replace turning.
  • Use slide sheets and at least two staff for transfers - never drag. Avoid doughnut/ring cushions (cause peripheral ischaemia) and do not massage over bony prominences.
  • Skin care: cleanse with pH-balanced cleanser and lukewarm water, pat dry, apply barrier film/cream for incontinence, no vigorous rubbing, no spirit or talc.
  • Prophylactic multi-layer silicone foam dressings on sacrum and heels for high-risk and ICU patients; rotate device sites and pad under devices.
  • Nutrition: screen all at-risk patients, refer to a dietitian, give high-protein oral nutritional supplements; maintain hydration.
• Indian practice and governance: pressure-ulcer prevalence/incidence is a mandatory nursing quality indicator under current NABH hospital standards (patient-safety and nursing-care chapters) and NABH nursing excellence certification; the Clinical Establishments (Registration and Regulation) Act, 2010 and state rules require defined standards of care; the Consumer Protection Act, 2019 and tort law make a hospital-acquired stage 3/4 injury with absent turning records a frequent negligence allegation. Nursing practice and education are regulated by the Indian Nursing Council under the Indian Nursing Council Act, 1947, with the National Nursing and Midwifery Commission Act, 2023 enacted to replace it - transition to the new Commission and its councils is still being rolled out, so verify current status locally. Soiled dressings and gauze go into yellow bags, blood-soaked contaminated plastics into red, needles/blades into white puncture-proof containers under the Bio-Medical Waste Management Rules, 2016 (as amended). Infection prevention follows NCDC/NABH hand-hygiene and surgical-site-infection surveillance guidance (WHO 5 moments).

Wound assessment and documentation

• Record each time: site (anatomical), stage/type, size (length × width × depth, cm), undermining/tunnelling with clock position, wound bed tissue (% granulation / slough / necrotic / epithelial), exudate amount (nil, scant, small, moderate, large) and type (serous, serosanguineous, sanguineous, purulent), odour, edges (attached, rolled/epibole, undermined, macerated), periwound skin, pain score, and signs of infection.
• Measure consistently: head-to-toe = length, side-to-side = width (perpendicular), depth with a moistened sterile swab at the deepest point; tunnelling depth and direction by clock face with 12 o'clock towards the head.
• Tools: PUSH tool (Pressure Ulcer Scale for Healing - area + exudate + tissue type, 0-17, falling score = healing), Bates-Jensen Wound Assessment Tool (13 items), Pressure Sore Status Tool.
• Infection: local signs - increasing pain, erythema >2 cm, oedema, heat, purulent exudate, friable bleeding granulation, odour, delayed healing, pocketing (mnemonics NERDS = superficial critical colonisation, STONEES = deep infection). Systemic - fever, raised TLC/CRP, spreading cellulitis, sepsis.
• Culture technique (Levine): cleanse with normal saline, debride slough, rotate the swab over 1 cm² of viable wound bed for 5 seconds with enough pressure to express fluid; tissue biopsy or needle aspiration is the gold standard. Do not swab pus from the surface or eschar alone.
• Vascular screening for leg ulcers: palpate pulses and measure ankle-brachial pressure index (ABPI) before applying compression; assess sensation with a 10 g Semmes-Weinstein monofilament in diabetes. Diabetic foot ulcers are graded by Wagner (0-5) or classified by SINBAD/University of Texas.

Wound bed preparation, dressings and advanced therapy

• TIME framework: Tissue (debride non-viable tissue), Infection/inflammation (control bacterial burden and biofilm), Moisture balance (moist, not wet, not dry), Edge advancement (treat epibole, undermining, reassess if no progress).
• Cleansing: irrigate with normal saline or potable water at low pressure (≈4-15 psi); avoid routine antiseptics (povidone-iodine, hydrogen peroxide, chlorhexidine) on granulating wounds - cytotoxic to fibroblasts; reserve antiseptics for critically colonised or infected wounds for a short, defined period.
• Debridement:
  • Autolytic - hydrogel/hydrocolloid lets the body's enzymes liquefy slough; slow, painless, selective.
  • Enzymatic - collagenase/papain ointment; selective, moderate speed.
  • Mechanical - wet-to-dry gauze, monofilament pads, irrigation, hydrosurgery; non-selective, painful.
  • Sharp/surgical - scalpel or curette at bedside or in theatre; fastest, needs a trained practitioner, used for sepsis and large eschar.
  • Biosurgical - sterile larval (maggot) therapy; highly selective.
  • Contraindicated on stable dry eschar over an ischaemic limb or heel, and in dry gangrene until revascularisation.
• Principle of moist wound healing: a moist bed speeds epithelial migration and autolysis and reduces pain; dry gauze dehydrates the bed and tears new tissue on removal.
• Dressing families: see the comparison table below.
• Negative pressure wound therapy (NPWT): sealed foam/gauze filler with continuous or intermittent subatmospheric pressure, usually −80 to −125 mmHg; removes exudate, reduces oedema and bacterial load, promotes granulation and wound contraction. Used for stage 3/4 pressure injuries, dehisced abdominal wounds, skin-graft bolstering, open fractures. Contraindicated over exposed vessels/organs/anastomoses, untreated osteomyelitis, malignancy in the wound, and with active bleeding or anticoagulant-related ooze.
• Other adjuncts: skin grafts and myocutaneous flaps for stage 3/4 ulcers, electrical stimulation, platelet-rich plasma and growth factors, collagen and skin substitutes, hyperbaric oxygen (selected diabetic foot ulcers), larval therapy, maggot-free biofilm-disrupting gels.
• Pain and dressing comfort: pre-medicate 30 minutes before dressing change, use silicone/atraumatic contact layers, soak adherent gauze with saline, avoid frequent unnecessary changes.
• Nutrition and medical management: 30-35 kcal/kg/day, 1.25-1.5 g/kg/day protein for an existing pressure injury, adequate fluid, and vitamin C/zinc/arginine if deficient; glycaemic control; treat anaemia, oedema and incontinence; systemic antibiotics only for spreading infection, osteomyelitis or sepsis - not for colonisation.

Key points

• Pressure injury - localised skin/soft-tissue damage over a bony prominence or under a device from sustained pressure or pressure with shear.
• Capillary closing pressure - about 32 mmHg; sustained interface pressure above this causes ischaemia.
• Stage 1 - non-blanchable erythema, skin intact; the blanch test distinguishes it from reactive hyperaemia.
• Stage 2 - partial-thickness loss or serum-filled blister; no fat, slough or eschar.
• Stage 3 vs 4 - fat visible = stage 3; fascia, muscle, tendon or bone visible or palpable = stage 4.
• Unstageable - depth hidden by slough/eschar; DTPI - persistent maroon/purple intact skin or blood blister.
• Mucosal injury - under a device on mucosa; never staged. Device-related injury - mirrors the device shape.
• Braden scale - 6 subscales, score 6-23; ≤18 at risk, ≤9 very high risk; assess within 8 hours of admission.
• SSKIN bundle - Surface, Skin inspection, Keep moving, Incontinence, Nutrition.
• 30° rule - 30° lateral tilt and head of bed ≤30°; avoid 90° side-lying; heels fully offloaded.
• Never - massage bony prominences, use ring cushions, drag the patient, or reverse-stage a healed ulcer ("stage 4 healing" not "now stage 2").
• Moist wound healing - keep the bed moist and the periwound dry; match dressing to exudate.
• TIME - Tissue, Infection, Moisture, Edge: the sequence of wound bed preparation.
• Levine technique - rotate swab over 1 cm² of viable tissue for 5 seconds after cleansing; tissue biopsy is the gold standard.
• Dehiscence - layers separate (days 5-10, serosanguineous leak); evisceration - viscera protrude: cover with sterile saline gauze, low Fowler's, nil orally, inform surgeon.
• NPWT - −80 to −125 mmHg; contraindicated over exposed vessels, malignancy and untreated osteomyelitis.
• Nutrition for healing - 30-35 kcal/kg/day and 1.25-1.5 g protein/kg/day with an open pressure injury.
• Waste - soiled dressings in yellow bags, sharps in white puncture-proof containers (BMW Rules, 2016 as amended).

Formulas and examples

Example 1 - Braden scoring and action. A 72-year-old man after a stroke: sensory perception very limited = 2, moisture very moist = 2, activity bedfast = 1, mobility very limited = 2, nutrition probably inadequate = 2, friction/shear problem = 1.

• Total = 2+2+1+2+2+1 = 10 → high risk (10-12 band; ≤9 would be very high risk).
• Plan: alternating-pressure mattress, 2-hourly turns with 30° tilt, heel-suspension boots, prophylactic sacral silicone foam dressing, barrier cream with incontinence care, dietitian referral, skin check every shift.

Example 2 - Wound area, healing rate and PUSH. A sacral stage 3 injury measures 4.2 cm (length) × 3.0 cm (width) with moderate exudate and a granulating bed.

• A₀ = 0.7854 × 4.2 × 3.0 = 9.9 cm² → PUSH area category (8.1-12.0 cm²) = 8; exudate moderate = 2; tissue = granulation = 2 → PUSH 12.
• After 2 weeks: 3.0 × 2.2 cm → Aₜ = 0.7854 × 3.0 × 2.2 = 5.2 cm²; exudate light = 1, granulation = 2 → area category (4.1-8.0) = 7 → PUSH 10.
• Percentage area reduction = (9.9 − 5.2)/9.9 × 100 = 47.5% in 2 weeks → ≈23.7% per week. More than 30-40% reduction by week 4 predicts healing, so continue the present plan.

Example 3 - Nutrition prescription. Woman, 62 kg, height 1.55 m, stage 3 pressure injury, serum albumin 2.8 g/dL.

• BMI = 62 ÷ (1.55)² = 62 ÷ 2.4025 = 25.8 kg/m².
• Energy = 30-35 × 62 = 1,860-2,170 kcal/day.
• Protein = 1.25-1.5 × 62 = 77.5-93 g/day (about 1.4 g/kg = 87 g chosen).
• Fluid ≈ 1 mL/kcal = 1,860-2,170 mL/day (adjust for cardiac/renal status); add vitamin C and zinc if deficient, and high-protein oral supplement twice daily.

Example 4 - ABPI before compression. Venous-looking medial malleolar ulcer: right ankle systolic 100 mmHg (highest of dorsalis pedis and posterior tibial), brachial systolic 125 mmHg.

• ABPI = 100 ÷ 125 = 0.80 → borderline, at the lower limit of the range (≥0.8) usually accepted as safe for compression. Confirm with vascular assessment, start compression cautiously under medical advice and monitor; an ABPI <0.8 would indicate significant arterial disease, where full high compression is unsafe and only reduced compression may be used on specialist advice.

Example 5 - Turning schedule and dressing cost. A bedfast patient on 2-hourly turns using a 4-position rotation (supine, right 30° tilt, left 30° tilt, semi-Fowler's).

• Position changes per 24 h = 24 ÷ 2 = 12; each position recurs 3 times a day; each turn documented with a skin check.
• Dressing comparison over 21 days: silicone foam ₹350 changed every 3 days = 7 changes = ₹2,450, nursing time 7 × 15 min = 1.75 h. Daily gauze with saline twice a day = 42 changes × ₹30 = ₹1,260, nursing time 42 × 15 min = 10.5 h, plus pain and tissue trauma at each removal. Illustrative prices only - rates vary by vendor and GST slab.

Where it is used

• Hospital bedside nursing: ICU, neuro and orthopaedic wards, spinal injury units and geriatric wards - daily Braden scoring, turning charts, dressing rounds; AIIMS, PGIMER, CMC Vellore, Tata Memorial, Apollo, Fortis and Manipal hospitals all run skin-integrity audits.
• Wound care nurse / stoma and wound ostomy continence (WOC) roles: specialist consults, NPWT management, dressing formulary decisions and staff training in large corporate and tertiary hospitals.
• Operation theatre and surgical nursing: positioning to prevent intraoperative pressure injury (long cardiac and spine surgeries), SSI bundles, drain and incision care.
• Home health, palliative care and rehabilitation: home-care agencies and hospices manage sacral and heel ulcers, teach family caregivers turning and nutrition; spinal-cord rehabilitation centres run pressure-relief training for wheelchair users.
• Community and NHM settings: ASHA/ANM and CHO-led care of diabetic foot ulcers and leg ulcers under Ayushman Bharat health and wellness centres; NPCDCS-linked foot screening.
• Industry and quality roles: medical-device and dressing companies (3M, Smith+Nephew, ConvaTec, Coloplast, Datt Mediproducts, Advanced Medical Technologies) employ nurses as clinical trainers and product specialists; NABH assessors and hospital quality teams audit pressure-injury incidence per 1,000 patient-days.

Interview questions

• Q: How do you distinguish a stage 1 pressure injury from reactive hyperaemia? A: Press the red area with a finger - reactive hyperaemia blanches and refills, whereas a stage 1 injury shows non-blanchable erythema; in dark skin tones rely on change in colour, warmth, firmness, bogginess and pain.
• Q: Why can a wound covered with eschar not be staged? A: The slough or eschar hides the wound base, so true depth is unknown; it is recorded as unstageable and staged only after debridement.
• Q: A patient's stage 4 ulcer is granulating and now 1 cm deep. How do you stage it? A: It stays stage 4 and is documented as a "healing stage 4 pressure injury"; pressure injuries are never reverse-staged because lost muscle and fat are replaced by scar, not original tissue.
• Q: What is the first nursing action for a stage 1 sacral injury? A: Relieve pressure from the site immediately - reposition off the sacrum using a 30° tilt, review the support surface, and increase the turning frequency; then manage moisture and nutrition.
• Q: Why are doughnut rings and massage over bony prominences avoided? A: Rings concentrate pressure on the surrounding tissue and cause venous congestion, and massage over a bony prominence can damage already ischaemic capillaries and deep tissue.
• Q: Which dressing would you choose for a heavily exuding sacral cavity wound with 50% slough? A: A calcium alginate or hydrofibre to pack and absorb, covered with a foam secondary dressing, with sharp or autolytic debridement of the slough - reassess daily for strike-through.
• Q: Why is povidone-iodine or hydrogen peroxide not used routinely on a granulating wound? A: They are cytotoxic to fibroblasts and keratinocytes and delay healing; normal saline irrigation is preferred, with antiseptics limited to infected or critically colonised wounds for a short, defined period.
• Q: What are the pressure points in the prone position? A: Forehead, cheeks and chin, ears, chest/breasts, genitalia in men, iliac crests, knees and dorsum of the toes - also the eyes and the sites of any device such as an ET tube.
• Q: How do you take a wound swab correctly? A: Cleanse the wound with saline and debride slough, then use the Levine technique - rotate the swab over 1 cm² of viable tissue for 5 seconds with pressure enough to express fluid; label and send promptly.
• Q: What would make you suspect wound infection rather than normal inflammation? A: Pain increasing after day 3-4, erythema extending more than 2 cm, purulent or malodorous exudate, friable bleeding granulation, wound breakdown or stalled healing, with fever and raised TLC/CRP in deep infection.
• Q: A post-laparotomy patient coughs and says something has "given way"; you see bowel at the incision. What do you do? A: Stay with the patient, place them in low Fowler's with knees flexed, cover the viscera with sterile saline-soaked gauze, keep them nil by mouth, monitor vitals for shock, inform the surgeon and prepare for emergency repair.
• Q: What are the contraindications to negative pressure wound therapy? A: Exposed blood vessels, organs or anastomoses, untreated osteomyelitis, malignancy within the wound, necrotic tissue with eschar, unexplored fistulae and active bleeding.

Common mistakes

• Reverse-staging a healing injury, or staging a deep tissue injury or an unstageable eschar-covered wound as stage 1 or 2.
• Calling a serum-filled blister stage 1 (it is stage 2) or confusing a blood-filled blister (DTPI) with stage 2.
• Labelling perineal moisture damage as a pressure injury - it has no bony prominence and no necrosis.
• Relying on a pressure-relieving mattress and skipping or poorly documenting turns; missing turning charts are the commonest finding in negligence claims and NABH audits.
• Packing a cavity too tightly or leaving gauze without counting pieces - causes pressure necrosis or a retained foreign body.
• Using dry gauze or wet-to-dry gauze on a clean granulating bed, or applying an absorbent alginate to a dry wound.
• Treating a positive swab from a colonised wound with systemic antibiotics, and forgetting that mucosal injuries cannot be staged.
• Measuring length and width inconsistently (not head-to-toe and perpendicular), making serial comparison meaningless.

Related topics

Perioperative nursing (positioning and surgical site care) · Diabetes and endocrine nursing (diabetic foot) · Critical care nursing (device-related injury, immobility) · Fundamentals of nursing: asepsis and infection control · Nutrition and dietetics in illness · Burns and plastic surgery nursing