Key Takeaways

  • Pressure injury staging (NPUAP): Stage 1 (non-blanchable erythema, intact skin), Stage 2 (partial thickness, blister), Stage 3 (full thickness into subcutaneous), Stage 4 (full thickness with bone/tendon exposure), Unstageable (obscured by slough/eschar)
  • The Wagner scale classifies diabetic foot ulcers: Grade 0 (at-risk), Grade 1 (superficial), Grade 2 (deep to tendon/joint), Grade 3 (deep with abscess/osteomyelitis), Grade 4 (partial gangrene), Grade 5 (whole foot gangrene)
  • Wound assessment uses MEASURES: Measure (length, width, depth), Exudate, Appearance, Suffering (pain), Undermining, Re-evaluate, Edge (wound margins)
  • Wound healing phases: hemostasis (minutes), inflammation (1-6 days), proliferation (4-24 days), remodeling (21 days to 2 years)
  • Debridement types: sharp/surgical (fastest, selective), enzymatic (topical agents like collagenase), autolytic (moisture-retentive dressings), mechanical (wet-to-dry, pulsed lavage)
  • Burns — Rule of Nines for adults: head 9%, each arm 9%, anterior trunk 18%, posterior trunk 18%, each leg 18%, perineum 1%
  • Burn depth: superficial (1st degree — epidermis, painful, red), superficial partial-thickness (2nd degree — into dermis, blisters), deep partial-thickness (into reticular dermis), full-thickness (3rd degree — painless, waxy/leathery)
  • Wound dressing selection: hydrogel (dry wounds, autolytic debridement), alginate (highly exudative wounds), foam (moderate exudate), hydrocolloid (light exudate, granulating wounds)
Last updated: February 2026

Integumentary System: Wound Care & Burns

The integumentary domain accounts for 4-5% of the NPTE, but questions tend to be very specific and detail-oriented. Mastery of wound classification systems, healing phases, and intervention selection is essential.


Wound Classification

Pressure Injury Staging (NPUAP/NPIAP 2019)

StageDescriptionTissue Involved
Stage 1Non-blanchable erythema of intact skinEpidermis — skin is not broken
Stage 2Partial-thickness skin loss with exposed dermis; may present as blisterEpidermis and part of dermis
Stage 3Full-thickness skin loss; subcutaneous fat may be visible; undermining/tunneling may occurThrough dermis into subcutaneous tissue
Stage 4Full-thickness tissue loss with exposed bone, tendon, muscle, or cartilageThrough all layers to deep structures
UnstageableFull-thickness loss obscured by slough (yellow) or eschar (black)Cannot determine depth until debrided
Deep Tissue Pressure InjuryPersistent non-blanchable deep red, maroon, or purple discoloration; intact or non-intact skinDeep tissue damage under intact surface

Key Rule: Pressure injuries can only be staged forward (worsening). A Stage 4 that heals does NOT become a Stage 3 — it is documented as a "healing Stage 4." Reverse staging is not used.

Wagner Classification (Diabetic Foot Ulcers)

GradeDescription
Grade 0No open lesion; at-risk foot with deformity or callus
Grade 1Superficial ulcer (epidermis and/or dermis)
Grade 2Deep ulcer to tendon, bone, or joint capsule
Grade 3Deep ulcer with abscess, osteomyelitis, or joint sepsis
Grade 4Localized gangrene (forefoot or heel)
Grade 5Extensive gangrene of entire foot

Wound Healing Phases

PhaseTimelineKey Events
HemostasisMinutesVasoconstriction, platelet aggregation, clot formation
Inflammation1-6 daysVasodilation, neutrophils and macrophages clean wound, cardinal signs (redness, heat, swelling, pain)
Proliferation4-24 daysGranulation tissue formation, angiogenesis, wound contraction, epithelialization
Remodeling (Maturation)21 days to 2 yearsCollagen reorganization, scar maturation; wound reaches maximum 80% of original tissue strength

Clinical Significance: A wound stuck in the inflammatory phase for more than 3 weeks is considered a chronic wound. Factors that impair healing include diabetes, vascular disease, malnutrition (especially protein, vitamin C, zinc), infection, smoking, and medications (corticosteroids, NSAIDs).


Debridement Types

TypeMethodSpeedSelectivityIndications
Sharp/SurgicalScalpel, scissors, curetteFastestSelective (can target necrotic tissue)Thick necrotic tissue, infected wounds, urgent debridement
EnzymaticTopical agents (collagenase/Santyl)SlowSelectivePatients unable to tolerate sharp debridement
AutolyticMoisture-retentive dressings (hydrogel, hydrocolloid)SlowestSelectiveClean wounds with light necrotic tissue
MechanicalWet-to-dry gauze, pulsed lavage, whirlpoolModerateNon-selective (removes healthy and necrotic tissue)Wounds with both necrotic and granulation tissue

Debridement Contraindication: Do NOT debride stable, dry eschar on the heels — it serves as a biological cover. Monitor for signs of infection.


Burns

Rule of Nines (Adults)

Body RegionPercentage of TBSA
Head and neck9%
Each upper extremity9% (total 18%)
Anterior trunk18%
Posterior trunk18%
Each lower extremity18% (total 36%)
Perineum1%
Total100%

Note: The Rule of Nines is modified for children: head is proportionally larger (18% for infants) and legs are smaller.

Burn Depth Classification

DepthLayers AffectedAppearanceSensationHealing
Superficial (1st degree)Epidermis onlyRed, dry, no blistersPainful3-7 days, no scarring
Superficial partial-thickness (2nd)Epidermis + superficial dermisRed, moist, blistersVery painful7-21 days, minimal scarring
Deep partial-thickness (2nd)Epidermis + deep dermisRed/white, may be moist or waxyDecreased sensation21-35 days, scarring likely
Full-thickness (3rd degree)All skin layersWhite, waxy, leathery, or charredPainless (nerves destroyed)Requires grafting
Subdermal (4th degree)Skin + underlying structuresCharred, exposed structuresNo sensationRequires surgery, amputation possible

Burn Rehabilitation Focus

  • Positioning: Position OPPOSITE to anticipated contracture (anti-deformity position)
  • Splinting: Used to maintain functional position and prevent contracture
  • ROM exercises: Begin immediately; active and passive motion to maintain joint mobility
  • Pressure garments: Applied after wound closure to minimize hypertrophic scarring (worn 23 hours/day for 12-18 months)
Test Your Knowledge

A patient has a pressure injury with exposed bone and tendon visible in the wound bed. This is classified as:

A
B
C
D
Test Your Knowledge

Using the Rule of Nines, an adult patient with burns to the entire anterior trunk and the entire right upper extremity has approximately what percentage of total body surface area (TBSA) burned?

A
B
C
D
Test Your Knowledge

Which type of debridement is the FASTEST and most selective method?

A
B
C
D
Test Your KnowledgeMatching

Match each wound dressing type to its primary indication.

Match each item on the left with the correct item on the right

1
Hydrogel
2
Alginate
3
Foam dressing
4
Hydrocolloid
Test Your Knowledge

A full-thickness (3rd degree) burn is typically:

A
B
C
D
Test Your KnowledgeFill in the Blank

Wounds achieve a maximum of approximately _____% of the original tissue tensile strength after complete remodeling.

Type your answer below

Test Your Knowledge

A pressure injury that is full-thickness with the wound bed obscured by yellow slough and black eschar is classified as:

A
B
C
D
Test Your Knowledge

In burn rehabilitation, the patient should be positioned in the _____ of anticipated contracture.

A
B
C
D
Test Your KnowledgeOrdering

Arrange the wound healing phases in their correct chronological order:

Arrange the items in the correct order

1
Proliferation (granulation tissue formation)
2
Hemostasis (clot formation)
3
Remodeling (scar maturation)
4
Inflammation (neutrophils and macrophages)
Test Your Knowledge

Pressure garments after burn wound closure should be worn:

A
B
C
D