Pressure Ulcers — Clinical Documentation Guide (2026)

🔍 Definition

A pressure ulcer (also called a pressure injury) is localized damage to the skin and underlying soft tissue, usually occurring over a bony prominence or in relation to a medical or other device. Injury results from intense and/or prolonged pressure, alone or in combination with shear. The tolerance of soft tissue for pressure and shear may also be affected by microclimate, nutrition, perfusion, co-morbidities, and the condition of the soft tissue. Per the National Pressure Injury Advisory Panel (NPIAP), the revised 2016 definition replaced the prior term “pressure ulcer” with pressure injury to capture soft-tissue damage that occurs without an open wound (e.g., Stage 1, Deep Tissue Pressure Injury). Despite this clinical shift, ICD-10-CM retains the heading Pressure ulcer in category L89, and coding professionals must be fluent in both terminologies.

Pressure injuries arise most often in patients who are immobile, malnourished, incontinent, or have diminished sensation. Common high-risk anatomical sites include the sacrum, heels, hips, elbows, ankles, and the back of the head. Facility-acquired pressure injuries Stage 3, Stage 4, and unstageable are Hospital-Acquired Conditions (HACs) under the CMS HAC program, directly affecting reimbursement and quality performance metrics.

🗂️ Alternative Terminology

🩺 Signs & Symptoms

Clinical presentation varies by stage:

• Stage 1: Non-blanchable erythema of intact skin over a bony prominence. Skin is intact; the area may be painful, firm, soft, warmer, or cooler than adjacent tissue. Darker skin tones may not show visible blanching — discoloration, warmth, edema, or induration are alternative indicators.
• Stage 2: Partial-thickness skin loss exposing the dermis. The wound bed is viable, pink or red, moist; may present as an intact or ruptured serum-filled blister. Adipose tissue and deeper structures are not visible.
• Stage 3: Full-thickness skin loss in which adipose tissue is visible; granulation tissue and epibole (rolled wound edges) may be present. Slough and/or eschar may be present. Depth varies by location — areas with significant adiposity can develop extremely deep wounds; areas that lack subcutaneous tissue (bridge of nose, ear, occiput, malleolus) present as shallow Stage 3.
• Stage 4: Full-thickness skin and tissue loss with exposed or directly palpable fascia, muscle, tendon, ligament, cartilage, or bone. Slough and/or eschar may be present. Tunneling and undermining are frequently present.
• Unstageable: Full-thickness skin and tissue loss in which the extent of tissue damage within the wound cannot be confirmed because it is obscured by slough or eschar. Only after enough slough/eschar is removed can the true stage be determined.
• Deep Tissue Pressure Injury (DTPI): Intact or non-intact skin with a localized area of persistent non-blanchable deep red, maroon, or purple discoloration or epidermal separation revealing a dark wound bed or blood-filled blister. Pain and temperature change often precede skin color changes. Prior term was “suspected deep tissue injury” (sDTI).

Systemic signs suggesting secondary infection or complications include fever, leukocytosis, malodorous wound drainage, surrounding cellulitis, crepitus (indicating gas-forming organisms), and osteomyelitis in wounds with bone exposure.

🧭 Differential Diagnosis

📋 Clinical Indicators for Coders/CDI

🦴 Anatomy & Pathophysiology

Pressure injuries result from a combination of external mechanical forces and tissue-level cellular responses. The primary mechanism is ischemia: sustained pressure (typically >32 mmHg — the average capillary closing pressure) occludes cutaneous and deep tissue blood flow, causing hypoxia, nutrient deprivation, and accumulation of metabolic waste products. Reperfusion injury during pressure relief also contributes to cell death through reactive oxygen species.

Shear forces compound ischemia by stretching and tearing blood vessels at the interface between bony anatomy and overlying tissue. Shear most commonly occurs when the head of the bed is elevated above 30 degrees while a patient slides inferiorly. Friction damages the epidermis, creating a portal of entry for pathogens and reducing the mechanical protection of superficial skin layers.

Tissue depth and composition influence which layer sustains injury first. Muscle is far more susceptible to pressure-induced ischemia than skin, which explains why deep tissue injuries (DTPI) can appear as intact-skin presentations while underlying muscle is already necrotic — a critical clinical concept for staging and coding.

The anatomic sites most at risk correspond to bony prominences:

• Sacrum/coccyx — supine patients; most common site
• Heels — second most common; minimal subcutaneous tissue over calcaneus
• Trochanters/hips — lateral recumbent position
• Ischial tuberosities/buttocks — prolonged sitting; wheelchair users
• Elbows, scapulae, occiput — repositioning challenges
• Malleoli, knees, ankles — lateral positioning

Comorbidities that impair skin integrity and healing include diabetes mellitus, peripheral arterial disease, heart failure, renal failure, malnutrition (albumin <3.5 g/dL, prealbumin <16 mg/dL), spinal cord injury, and long-term corticosteroid use. The NPIAP 2016 revised staging system acknowledges that microclimate (moisture and temperature at the skin surface), nutrition, and perfusion are key modifying factors in tissue tolerance.

💊 Medication Impact / Treatment

Pressure ulcers/injuries are primarily managed with wound care, offloading, and nutritional support. Pharmacological agents play an adjunctive, site-specific role. CDI specialists should document any relevant topical or systemic agents that affect healing trajectory or complexity of care.

Topical Agents

• Silver sulfadiazine (SSD) cream — broad-spectrum topical antimicrobial; used in colonized or critically colonized wounds; does not systematically code an infection diagnosis without provider documentation of infection
• Collagenase (Santyl) — enzymatic debridement agent; selectively digests denatured collagen in wound eschar; requires documentation of wound type and clinical indication to support medical necessity; HCPCS supply coding may apply under Part B outpatient settings
• Cadexomer iodine, medical-grade honey (e.g., Medihoney) — antimicrobial wound dressings; coded via HCPCS A-series wound dressing codes
• Becaplermin (Regranex) gel — recombinant PDGF; FDA-approved for diabetic neuropathic ulcers; occasionally used off-label for pressure injuries; boxed warning for remote malignancy risk

Systemic Pharmacology

• Antibiotics (systemic) — reserved for documented cellulitis, bacteremia, osteomyelitis, or sepsis arising from infected pressure ulcer; correct coding requires provider documentation of infection + causative organism when known (e.g., L89.313 + L03.211 right lower leg cellulitis + causative organism code)
• Nutritional supplements — protein supplements (Arginine, zinc, Vitamin C) support wound healing; malnutrition (E40–E46) should be coded when documented to support medical necessity and DRG severity
• Opioid analgesics / neuropathic pain agents — pain management for Stage 3/4 wounds; secondary diagnoses may contribute to complexity

Preview ends here. The full guide continues with FY2026 ICD-10-CM code sets, CPT surgical coding, MS-DRG mapping, reimbursement guidance, CDI query templates, and an audit checklist — all available to CCO CDG members.

📘 ICD-10-CM Guidelines (FY2026)

Pressure ulcer coding is governed by ICD-10-CM Official Guidelines Section I.C.12.a (FY2026). Key rules include:

Guideline Summary: Section I.C.12.a Pressure Ulcers

1. Combination codes: Category L89 codes are combination codes identifying site, stage, and (in most cases) laterality. A single L89 code captures all three elements for each distinct ulcer.
2. Multiple ulcers: Assign as many L89 codes as necessary to identify all pressure ulcers present. No bilateral combination codes exist — each side is coded separately.
3. Stage assignment by nursing: Coders may rely on nursing documentation to assign the stage; however, the physician/provider must document the diagnosis of pressure ulcer itself. If the stage documented is not found in ICD-10-CM, query the provider for clarification.
4. Healing vs. healed: Healing pressure ulcers are coded to the site and current stage documented. A fully healed pressure ulcer is not coded. If a ulcer is present on admission and heals prior to discharge, code the site and stage at admission.
5. Progression during admission: When a pressure ulcer is present on admission at one stage and advances to a higher stage during the stay, two codes are assigned: (a) the site/stage at admission, and (b) the same site with the highest stage during the stay. Both codes receive POA indicator “Y” because the original ulcer was POA (ACDIS Q&A citing Coding Clinic 4Q 2008, p. 194).
6. Unstageable vs. unspecified: Unstageable (6th character 9) = wound cannot be staged clinically (covered by eschar/slough or skin graft). Unspecified stage (6th character 0) = stage was not documented. Query to resolve unspecified where possible — it carries no HCC mapping and limited reimbursement impact.
7. Deep Tissue Pressure Injury (DTPI): Coded with the 6th character “6” in the L89 category (e.g., L89.006 for unspecified elbow, L89.616 for right heel). Do not confuse DTPI with Stage 1 or unstageable. DTPI represents intact or non-intact skin with deep purple/maroon discoloration typically evolving over hours to days.
8. Code also gangrene: An instructional note under L89 directs coders to Code also any associated gangrene (I96) when gangrene is documented in connection with a pressure ulcer. I96 is coded as an additional diagnosis.
9. Present on Admission (POA): The POA indicator is mandatory for inpatient admissions on Medicare claims. Pressure ulcer Stage 3, Stage 4, or unstageable is a Category 2 HAC when NOT documented as POA. If POA = “N,” “U,” or “W,” the case may lose the DRG payment adjustment that the pressure ulcer diagnosis would otherwise provide. The HAC modifier is triggered at the claim level, removing the CC/MCC weight from the code if not POA.
10. POA for progressed ulcers: Per Coding Clinic 4Q 2008, if a Stage 2 ulcer is POA and progresses to Stage 3 during the admission, the Stage 3 code is still considered POA because the original ulcer was present on admission. This is a frequently tested rule and a major CDI/auditor focus.

MS-DRG Impact

Pressure ulcer Stage 3 qualifies as a Major Complication/Comorbidity (MCC) and Stage 4 also qualifies as an MCC under the MS-DRG grouping logic, significantly elevating DRG base payment when coded as a secondary diagnosis — provided the POA indicator is “Y.” Stage 2 typically maps as a CC. Stage 1 and unspecified stage generally provide no CC/MCC value. When POA = “N,” the MS-DRG system treats the HAC-linked code as if it were not present, reverting to the lower-weighted DRG.

🔢 ICD-10-CM Code Set (FY2026)

Category L89 is organized by anatomical site with sub-categories for laterality. The 6th character indicates stage: 0 = unspecified, 1 = Stage 1, 2 = Stage 2, 3 = Stage 3, 4 = Stage 4, 6 = Deep Tissue Pressure Injury, 9 = Unstageable. All codes verified against the FY2026 ICD-10-CM tabular list.

🔎 Indexing

To locate pressure ulcer codes in the ICD-10-CM Alphabetic Index (FY2026 tabular/alphabetic index):

• Main term: Ulcer, pressure → subcategory by site → subcategory by stage
• Alternative entry: Pressure, ulcer (chronic)/(decubitus) — redirects to Ulcer, pressure
• For DTPI: Injury, pressure-induced deep tissue damage → by site (e.g., heel → L89.6-6)
• For decubitus: Decubitus (ulcer) → see Ulcer, pressure
• Gangrene associated: Gangrene, pressure ulcer → I96 + L89.xxx instructional note

The tabular note under the L89 category reads: “Code first any associated gangrene (I96)” — though in practice this means “code also” and either order is acceptable as a secondary diagnosis; some instructional notes in ICD-10-CM are imprecise on sequencing of same-level secondary diagnoses.

🏥 CPT (2026)

Surgical and procedural coding for pressure ulcers involves multiple CPT families depending on the intervention performed. All codes verified per AMA CPT 2026.

🧾 HCPCS (2026)

📚 AHA Coding Clinic (Recent Guidance)

The following represents key AHA Coding Clinic guidance relevant to pressure ulcer documentation and coding, based on published guidance from the AHA Central Office (AHA Coding Clinic Advisor):

• Coding Clinic, 4Q 2008, p. 194: Pressure ulcer present on admission at a lower stage (e.g., Stage 2) that progresses to a higher stage (e.g., Stage 3) during the hospital stay should have the Stage 3 coded as POA = “Y” because the original ulcer was present on admission. This is foundational guidance for HAC determination and is frequently referenced in audit contexts. (ACDIS Q&A summary)
• Coding Clinic, 1Q 2020: New guidelines clarified that when a pressure ulcer is present on admission as “healing” at a specific stage, code the stage documented at admission. If the ulcer is fully healed, no code is assigned.
• Coding Clinic guidance on DTPI: Deep tissue pressure injury (DTPI) is coded using the 6th character “6” codes introduced in FY2020. DTPI should not be coded as unstageable — the two conditions represent distinct clinical entities. DTPI has an intact or minimally broken skin surface with deep purple/maroon discoloration, while unstageable represents inability to visualize the wound depth due to eschar/slough coverage.
• Coding Clinic on nursing documentation: Nurses may document pressure ulcer stage and coders may code from this documentation, but the diagnosis of pressure ulcer itself (the condition) must be documented by the physician or provider. If only nursing documents the presence of a pressure ulcer and the physician has not acknowledged it, a query is warranted.
• Coding Clinic on multiple pressure ulcers: Assign a separate code for each pressure ulcer. If a patient has bilateral heel pressure ulcers, two codes are required (right heel and left heel), each with the applicable stage 6th character.

💰 HCC / Risk Adjustment (v28)

Under CMS-HCC Model V28 (fully operative for payment year 2026 — 100% V28), pressure ulcers map to three distinct HCC categories based on depth of tissue loss. Accurate staging documentation is therefore essential for risk adjustment capture in Medicare Advantage.

Sources: Carina Health Network V24 vs V28 Analysis; DoctusTech HCC V28 Series.

V28 change from V24: Stage 4 (necrosis to muscle/tendon/bone) maps to the new HCC 379 with a slightly higher RAF weight than V24 HCC 157. Stage 3 (full thickness) maps to HCC 381. Stage 2 (partial thickness) maps to HCC 382 — this is notable because Stage 2 now explicitly maps to a payment HCC in V28, providing documentation incentive for accurate staging. Stage 1 and unspecified stage do not generate HCC mapping.

✍️ CDI Query Templates

🧑‍⚕️ Treatments (Clinical)

Clinical management of pressure ulcers/injuries follows evidence-based guidelines from the NPIAP Prevention and Treatment of Pressure Injuries Clinical Practice Guideline (most recently updated 2019). Treatment is multi-modal and depends on stage:

Stage 1

• Pressure offloading (repositioning every 2 hours, heel offloading devices)
• Moisture barrier creams to prevent MASD overlap
• Nutritional optimization
• Transparent film or thin foam dressings to reduce friction

Stage 2

• Moisture-retentive dressings: hydrocolloids, foam dressings, transparent films
• Avoid wet-to-dry gauze (non-selective, causes trauma)
• Blister management: leave intact unless large or painful; drain aseptically
• Continued repositioning and offloading

Stage 3 / Stage 4

• Surgical consultation for debridement and wound reconstruction when clinically appropriate
• Debridement modalities: sharp/surgical (CPT 11042–11047), enzymatic (collagenase), autolytic (moisture-retentive dressings), mechanical (irrigation)
• Negative pressure wound therapy (NPWT/VAC) — promotes granulation, reduces edema; CPT 97605–97608
• Advanced wound dressings: alginates, hydrofibers, foam, cadexomer iodine for infected wounds
• Surgical reconstruction options: primary closure, skin graft, local flap (rotation, advancement), pedicle myocutaneous flap (CPT 15920–15958)
• Treatment of comorbidities: optimization of nutrition (high protein diet, micronutrient supplementation), glycemic control, vascular optimization

Deep Tissue Pressure Injury (DTPI)

• Protect from further pressure/shear with offloading
• Avoid aggressive debridement of stable heel DTPI with dry eschar (per NPIAP guidelines)
• Monitor closely for evolution: may resolve, or may open into Stage 3/4 wound requiring active management
• Do not massage area

Support Surfaces

• Group 1 (E0181, E0184–E0199): Standard overlays and replacements; indicated for immobile patients or any-stage ulcer present
• Group 2 (E0193, E0277, E0371–E0373): Powered low air-loss or alternating pressure systems; required for non-healing Stage 2 on trunk/pelvis, or Stage 3/4; Medicare requires prior authorization (per CGS Medicare LCD L33642)
• Group 3 (E0194): Air-fluidized beds; completely immobile patients; requires physician documentation of medical necessity

🎓 Patient Education / Summary

Patient and caregiver education is central to pressure injury prevention and management, particularly for patients with spinal cord injury, limited mobility, or who are returning home after hospitalization.

Key Teaching Points

• What causes a pressure injury: Prolonged pressure on bony areas cuts off blood flow to the skin. The longer the pressure, the more serious the injury. Even a few hours of unrelieved pressure can cause permanent damage.
• Risk assessment: Anyone with limited mobility, reduced sensation, poor nutrition, or medical devices is at risk. Common risk tools include the Braden Scale (scored at admission and regularly thereafter).
• Repositioning: Change position at least every 2 hours when in bed; lift and shift (not slide) when moving; use a tilt-in-space wheelchair and relieve pressure every 15–30 minutes when seated.
• Skin inspection: Check the entire body daily, especially bony prominences. Look for redness that does not fade within 30 minutes of pressure relief. Report early changes to a nurse or physician immediately.
• Nutrition: Adequate protein intake is essential for tissue repair. A dietitian consultation is recommended for patients with Stage 3/4 injuries.
• Wound care at home: Follow nurse/provider instructions for dressing changes. Keep wound moist and protected. Watch for signs of infection: increased redness, warmth, swelling, pus, fever, or worsening pain.
• Support surfaces: Use the prescribed pressure-reducing mattress or cushion. Do not substitute with standard mattresses or sitting cushions that are not designed for pressure redistribution.
• Incontinence management: Moisture from incontinence significantly increases pressure injury risk. Use moisture barrier creams and incontinence pads; report skin breakdown promptly.
• When to seek urgent care: Fever, confusion, rapidly spreading redness, or a wound that suddenly smells foul or has green/black discharge may indicate serious infection — seek care immediately.

For patient handouts and resources, the National Pressure Injury Advisory Panel (NPIAP) provides free educational materials for patients and caregivers.

About this Guide

This Clinical Documentation Guide is published by CCO Academy and is intended for credentialed coding, CDI, and clinical documentation professionals. Content is updated for FY2026 ICD-10-CM (effective October 1, 2025). All code assignments should be verified against the official ICD-10-CM Tabular List, AHA Coding Clinic, and applicable payer-specific policies. This guide does not constitute legal, medical, or compliance advice.

Last reviewed: April 2026 · Next scheduled review: October 2026 (FY2027 update)