Pressure Injuries

A pressure injury (PI) — previously called a pressure ulcer, decubitus ulcer, or bedsore — is localized damage to the skin and/or underlying soft tissue, usually over a bony prominence, caused by intense and/or prolonged pressure, or pressure combined with shear.^[1] When external pressure on tissue exceeds capillary closing pressure, blood vessels occlude, perfusion falls, and tissue necrosis follows — this can begin within roughly 1 to 6 hours of sustained, unrelieved loading over a bony prominence, and less pressure is needed to cause ischemia in a patient with impaired circulation, on a vasopressor, or with impaired oxygenation. The injured area may present as intact discoloured skin or an open wound and is staged (Stage 1 through 4, Unstageable, or Deep Tissue Injury) to describe the depth of tissue involvement at the time of assessment — staging is not used to track healing progress, since a pressure injury does not heal by reverse-staging.^[2] Pressure relief is the central intervention for both prevention and treatment: no dressing, topical agent, or systemic therapy can heal a pressure injury while the causative pressure and shear remain unaddressed.

A pressure injury may present anywhere along a spectrum from intact but discoloured skin through full-thickness tissue loss with exposed bone. Use the National Pressure Injury Advisory Panel (NPIAP) staging system for every assessment — staging is specific to pressure injuries and should not be applied to other types of skin injury (e.g., moisture-associated skin damage, a traumatic wound, or a venous/arterial ulcer — see the comparison table in Assessment & Diagnosis).^[2]

Medical device-related and mucosal membrane pressure injuries

A medical device-related pressure injury results from a device applied for a diagnostic or therapeutic purpose (e.g., an oxygen tube, catheter, splint, or cast), and generally conforms to the pattern or shape of the device. A mucosal membrane pressure injury occurs on a mucous membrane at a site where a medical device was used (e.g., an oral airway or urinary catheter) — because of the anatomy of mucosal tissue, these injuries cannot be staged using the skin staging system above.

Assessing pigmented skin

Blanching may not be visible in darkly pigmented skin, and its colour may differ from the surrounding skin. Instead of relying on blanching alone, look for changes in skin tone, temperature, and tissue consistency compared to adjacent skin — colour changes may be easier to identify after gently moistening the skin.

• Decreased mobility or activity — the most consistent independent predictor of pressure injury risk.^[3]
• Impaired skin perfusion (peripheral vascular disease, hypotension, shock, vasopressor use).
• Poor skin condition (dry, fragile, or previously injured skin).
• Increased skin moisture from incontinence, perspiration, or wound drainage.
• Older age.
• Poor nutritional status, including low serum albumin or hemoglobin.
• Decreased overall general health status and multiple comorbidities.
• Abnormal laboratory values reflecting inflammation, infection, or poor nutrition (e.g., an abnormal white blood cell count, elevated urea).
• Spinal cord injury or another condition causing sensory or motor impairment.
• Critical illness, prolonged surgery, or vasopressor therapy.
• Smoking.
• A medical device in prolonged contact with the skin (tubing, a catheter, a splint, or a cast).
• End-of-life status, where tissue tolerance for pressure can decline as part of overall physiologic decline.

Differentiating a pressure injury from other chronic wounds

A skin tear — a traumatic separation of skin layers from shear, friction, or blunt trauma against fragile skin — is a further, easily distinguished mimic: acute onset at a known moment of trauma, an irregular wound with a visible skin flap, and no relationship to pressure over a bony prominence.

Determining healability

After identifying and addressing the cause of the wound, classify it before selecting local wound care: a healable wound has no known factor preventing healing and is managed to achieve complete closure; a nonhealable wound occurs in a patient who lacks the physical capacity to heal (e.g., uncorrectable arterial insufficiency, a malignant wound, end-of-life status) and is managed to control pain and infection risk rather than pursue closure; a maintenance wound is healable in principle but cannot currently heal because of an unaddressed patient- or system-level barrier (e.g., no access to an appropriate support surface).

Vascular assessment before débridement

Before any method of débridement on the lower extremity, assess arterial supply — palpate pedal pulses, check capillary refill, and obtain an ankle-brachial index or toe pressure where available — to rule out arterial compromise that would prevent healing after débridement.

Diagnosing infection

Diagnosis is based on the clinical picture together with culture results, not on the classic signs of cellulitis alone, since these are frequently absent. Possible clinical signs include a wound that is not healing as expected, new or worsening pain, increased exudate, and a new foul odour. If infection is suspected, obtain a quantitative wound culture using the Levine technique: clean the wound first, then apply a culture swab to about a 1 cm² area of clean wound tissue with enough pressure to express fluid from the tissue, rotating the swab over that area for about 5 seconds.^[4] A qualitative swab is not diagnostic on its own, since every pressure injury contains bacteria — heavy growth on a quantitative culture in combination with clinical signs supports the diagnosis of infection.

• Prevent new pressure injuries from developing in an at-risk patient.
• Achieve complete healing of a healable wound.
• In a nonhealable or maintenance wound, prevent further tissue damage and control the wound rather than pursuing healing.
• Manage pain associated with the wound itself and with wound-care procedures.
• Prevent, recognize, and treat infection when it is present.
• Preserve function and quality of life, including minimizing disruption to the patient's daily activities from the wound-care schedule.

Repositioning

Implement a repositioning schedule to protect intact skin and avoid placing weight directly on bony prominences.^[6] Reposition a patient who cannot reposition themselves about every 2-4 hours while in bed (adjusted for overall condition, tolerance, mobility, and the support surface in use) and about every 15 minutes while sitting. Limit head-of-bed elevation to 30 degrees or less where medically feasible, and use lifting sheets, wedges, and pillows to reposition in a way that minimizes friction and shear.

Support surfaces

A patient at high risk of a pressure injury should not remain on a standard mattress. A reactive support surface changes load distribution only in response to applied load (e.g., air, water, gel, or foam mattresses/overlays, low-air-loss mattresses, air-fluidized mattresses); an active support surface (alternating-pressure mattresses) changes load distribution with or without applied load. No single specialized surface has been shown to be clearly superior to another — select based on patient risk level, wound status, and setting.^[7]

Pressure-relieving devices

Use soft pillows or foam wedges between bony prominences (e.g., knees, ankles) and to suspend the heels off the mattress, independent of the support surface in use. Medical-grade sheepskin overlays can reduce pressure injury risk. Avoid donut-shaped seat cushions — they concentrate rather than relieve pressure.

Medical devices

Avoid positioning a patient directly onto a medical device such as tubing or a drainage system. Remove a device that is a potential source of pressure as soon as medically feasible, remove any sling not intended to remain under the patient after a transfer, and inspect the skin under a device regularly, keeping it clean and dry.

Skin care and wound cleansing

Keep intact skin clean and adequately hydrated using nonalkaline cleansers, and clean up promptly after an episode of incontinence, using a barrier product to protect skin from moisture damage. Cleanse the wound at initial assessment and at every dressing change: warm the cleansing solution to room temperature, then gently irrigate with enough solution to cover the wound surface (at least 100-150 mL, more for a larger wound) at a nontraumatic pressure — a 30-35 mL syringe with an 18- or 19-gauge angiocatheter, or a single-use 100 mL squeeze bottle, provides an appropriate irrigation pressure. Tap water, sterile normal saline, and commercial wound cleansers are all reasonable choices for most wounds; reserve an antimicrobial wound cleanser (e.g., containing acetic acid, chlorhexidine, octenidine, or polyhexamethylene biguanide) for a wound with high bacterial colonization or suspected/confirmed infection. Pat the wound and surrounding skin dry afterward to help the dressing adhere.

Dressing selection by wound characteristics

Select a secondary dressing that maintains a moist wound bed without macerating the surrounding skin, controls exudate, provides thermal stability, and minimizes trauma on removal; reassess the choice at least weekly as the wound changes.

Débridement

Débridement removes devitalized tissue to allow granulation and re-epithelialization, prevent infection, and convert a chronic wound toward the environment of an acute, healing wound. Confirm adequate arterial supply before débriding a lower-extremity wound (see Assessment & Diagnosis), and do not débride stable, dry, adherent eschar on an ischemic limb or the heel unless infection is suspected. Select the method appropriate to the wound, setting, and available training: conservative sharp débridement (removing only nonviable tissue with sterile instruments, generally painless) is commonly performed at the bedside; surgical/sharp débridement (removing nonviable and some viable tissue) causes pain and bleeding and needs adequate anesthesia and, for larger amounts of tissue, an operating room; autolytic débridement uses a moisture-retentive dressing to soften and liquefy nonviable tissue over time and is painless but not recommended for an infected wound; mechanical débridement includes wound irrigation, polyacrylic microfibre pads, and low-frequency ultrasound (which disperses bacterial biofilm and can stimulate healing) — avoid wet-to-dry gauze dressings as a débridement method, since removing a dried-on dressing causes pain and traumatizes healthy tissue; enzymatic débridement uses a proteolytic agent to digest devitalized tissue and requires the wound to be kept moist to remain effective; biologic (larval) débridement is available through Health Canada's Special Access Program.

Nutrition

Assess every at-risk or affected patient for malnutrition and develop an individualized nutrition plan; involve a dietitian where available.^[8] Adequate energy and protein intake support tissue repair — a reasonable general target for a patient with an existing pressure injury is approximately 30-35 kcal/kg/day and 1.25-1.5 g/kg/day of protein, individualized to nutritional status, renal function, and overall goals of care, with a multivitamin/mineral supplement considered if dietary intake is inadequate. Evidence for any single nutritional supplement (e.g., arginine, glutamine, zinc, vitamin C) preventing or healing a pressure injury on its own is limited — treat adequate overall nutrition as the essential adjunct rather than relying on a specific supplement.

Smoking cessation

Nicotine, carbon monoxide, and hydrogen cyanide in cigarette smoke impair tissue oxygenation and delay wound healing. Encourage every patient with a pressure injury to quit smoking and refer to an appropriate cessation program or resource.

Pain, psychosocial, and financial support

Develop a patient-specific pain-management plan (see Pharmacologic Treatment Options and Drug Tables). Screen for anxiety, depression, and disrupted quality of life, and offer anxiety-reduction techniques, cognitive behavioural therapy, or a support group where appropriate; schedule wound care around important patient activities where possible, and choose a less cumbersome or lower-odour dressing (e.g., avoid a hydrocolloid dressing) when this meaningfully improves quality of life. Ask about financial barriers to dressings or medications not covered by insurance, and involve a social worker where needed.

Other adjunct wound-care therapies

Several additional therapies are used or promoted for pressure injury healing despite limited randomized trial evidence, and are considered adjuncts rather than routine care: surgical reconstruction (débridement with a skin flap) for a stage 3 or 4 injury not responding to standard care, in a patient who can tolerate anesthesia and postoperative rehabilitation; negative pressure wound therapy, which applies controlled suction to a covered wound to remove exudate and promote granulation tissue, contraindicated with untreated osteomyelitis, an untreated fistula, or proximity to major vessels; electrical stimulation, with evidence suggesting a possible benefit for healing rate but not yet sufficient to support routine use; and therapeutic ultrasound, electromagnetic therapy, ultraviolet phototherapy, hyperbaric oxygen, and anabolic steroids, none of which currently have adequate evidence to support routine use.^[1]

Pregnancy

A pressure injury in pregnancy is uncommon but can occur with prolonged immobility (e.g., bed rest for a pregnancy complication, or a prolonged labour). Prevention and pressure-relief principles apply unchanged. If a topical antimicrobial is needed, avoid silver sulfadiazine at or near term given the theoretical kernicterus risk from sulfonamide-related bilirubin displacement. Avoid an NSAID for wound pain, particularly in the third trimester; acetaminophen remains the preferred basal analgesic.

Breastfeeding

Standard local wound care and most systemic antibiotics used for a spreading pressure-injury infection (penicillins, cephalosporins, metronidazole) are compatible with breastfeeding at usual doses. Avoid applying silver sulfadiazine directly to or near the breast/nipple area.

Pediatrics

Pressure injuries are less common in children than in adults, but medical device-related injury is an important and often predominant pattern in this age group — for example, from a pulse oximetry probe, nasal cannula, or cast — rather than the classic bony-prominence pattern. Use an appropriately sized device, pad or reposition the device site, and inspect the skin under the device regularly. Silver sulfadiazine is contraindicated in infants under 2 months of age.

Spinal cord injury

Lifetime pressure injury risk is high given the combination of immobility, sensory loss, and altered tissue tolerance. The bony-prominence pattern at risk depends on positioning (ischial tuberosities and sacrum in a seated wheelchair user; sacrum, heels, and occiput in a patient who is primarily supine) — an individualized seating and pressure-mapping assessment by occupational therapy is valuable.

Critical illness

Vasopressor use and hemodynamic instability lower the pressure threshold needed to cause tissue ischemia. Correctly implemented prevention can still be insufficient in a severely hemodynamically compromised patient — document this clearly rather than assuming a new injury reflects a prevention failure.

Palliative and end-of-life care

A pressure injury near the end of life may be genuinely nonhealable regardless of care quality, sometimes developing and deteriorating rapidly in a patient's final days to weeks. Shift the goal explicitly to comfort — pain, odour, and exudate control — rather than pursuing closure, and communicate this goal shift clearly to the patient and family so a nonhealing wound is not mistaken for inadequate care.

Renal and hepatic impairment

Adjust systemic antibiotic dosing for renal function per standard renal dosing references. Use silver sulfadiazine with caution in significant renal or hepatic impairment, since systemic sulfonamide absorption (proportional to the treated surface area) is cleared by these organs.

Older adults

Most pressure injuries occur in older adults; age itself is a contributing risk factor through thinner skin, reduced subcutaneous tissue, and multimorbidity. Review the medication list specifically for an agent that impairs wound healing (see Common Errors to Avoid and Drug Tables).

• Reassess pressure-injury risk on admission, at any transition between care settings, and with any major change in health status or mobility.
• Measure and photograph the wound at every dressing change, or at least weekly, to track objective change in size, depth, and tissue type.
• Do not use the staging system to track healing progress — a healing stage 4 injury does not become a "stage 3" and then a "stage 2"; use wound measurement instead.^[2]
• Reassess the dressing choice at least weekly, and any time exudate volume, odour, or the surrounding skin condition changes.
• Monitor nutritional status and intake regularly, particularly protein intake, and involve a dietitian for an at-risk or malnourished patient.
• Reassess pain at every dressing change using a validated pain scale, and adjust pre-procedural analgesia if pain is inadequately controlled.
• Watch specifically for the red-flag signs described above at every assessment, since classic infection signs are frequently blunted or absent in a pressure injury.

1. Confirm pressure relief is actually being implemented as prescribed — repositioning schedule adherence, correct support surface, and true offloading of the affected area — before assuming the dressing or drug therapy has failed.
2. For a lower-extremity or heel wound, reassess arterial supply (pedal pulses, capillary refill, ankle-brachial index) if this was not already done.
3. Reassess nutritional status and intake; correct significant protein-calorie malnutrition or a micronutrient deficiency before expecting further healing progress.
4. Reassess for infection or a high bacterial bioburden impeding healing — obtain a quantitative wound culture (Levine technique) if not already done, and consider a topical antimicrobial/antiseptic trial if locally infected.
5. Reassess the débridement plan — nonviable tissue blocking the wound bed prevents healing; select or change the débridement method appropriate to the wound and setting.
6. Reassess the dressing choice against the current exudate level and wound depth — an overly absorbent dressing dries the wound bed, while one that is not absorbent enough macerates the surrounding skin.
7. Reconfirm the healability classification — a wound not progressing despite an optimized plan may genuinely be nonhealable or a maintenance wound limited by an unaddressed system-level barrier, in which case the goal should shift from healing to symptom control rather than escalating local therapy indefinitely.
8. Refer to a specialist wound care service, or to plastic, general, or vascular surgery, if the wound remains healable in principle but is not responding to an optimized plan, or if surgical reconstruction or an advanced adjunct therapy is being considered.

• Using a donut-shaped seat cushion — it concentrates rather than relieves pressure.
• Using a wet-to-dry gauze dressing as a débridement method — removing the dried dressing causes pain and traumatizes healthy tissue.
• Applying a topical antibiotic or antiseptic routinely to a clean, uninfected wound — no proven benefit, and it promotes resistance and sensitization.
• Softening or removing stable, dry, adherent eschar on an ischemic limb or the heel — this eschar is protective; débridement here should only be considered if infection is suspected.
• Using the pressure-injury staging system to monitor healing progress instead of wound measurement — staging describes worsening, not the reverse process of healing.
• Missing an NSAID, a systemic corticosteroid, or another medication listed in Drug Tables as a contributor to delayed healing in a patient whose wound is not progressing as expected.
• Proceeding with débridement of a lower-extremity wound without first assessing arterial supply.
• Choosing a low-absorbency dressing (e.g., a hydrogel) for a heavily exudating wound, or a highly absorbent dressing (e.g., an alginate) for a dry, low-exudate wound.
• Overlooking nutrition — not assessing and addressing protein-calorie status in a patient with a nonhealing wound.
• Performing a painful dressing change or débridement procedure without first providing adequate anticipatory analgesia.
• Assuming the absence of classic cellulitis signs (erythema, edema, warmth) rules out infection in a pressure injury — these signs are frequently absent even with true infection.

How to use this table: Doses are adult doses and require patient-specific confirmation, including renal/hepatic adjustment. Select any drug name to open its complete Pharmasist Drug Database page.

Topical antimicrobials and antiseptics for a locally infected wound

Reserve for a wound with clinical signs of local infection or a heavy bacterial burden — not for routine use on a clean, uninfected wound.

Evidence note: a systematic review found insufficient evidence to recommend one topical antimicrobial or antiseptic agent over another for a pressure injury, and did not support routine topical antibiotic use.^[5]

Systemic antibiotics for spreading infection or suspected osteomyelitis

Reserve for a pressure injury with spreading infection, systemic signs, or confirmed/strongly suspected osteomyelitis — not for a locally infected wound without spreading or systemic signs. See the Diabetic Foot Infections and Bacterial Skin Infections chapters for more detailed antibiotic-selection guidance in a comparable chronic, potentially polymicrobial wound infection.

Analgesics for wound pain and wound-care procedures