Nursing care
Pressure Injuries nursing care: what to assess and what to do first
Written and reviewed by Dana Whitfield, RN, MSN · 7 min read · Updated September 2026
Short answer
Pressure injuries are staged by what is visible in the wound bed, from intact but discoloured skin at stage 1 through to full-thickness tissue loss at stage 4. An unstageable wound is not a missing category, it is a wound where slough or eschar hides the base, and it stays unstageable until that tissue is debrided and the true depth can be seen.
What it is and why it happens
A pressure injury is localised damage to skin and underlying tissue caused by sustained pressure, or pressure combined with shear, over a bony prominence. Capillary occlusion beyond roughly 32 mmHg cuts off local blood flow, and if that pressure is not relieved, tissue ischaemia progresses to necrosis. Time matters more than force here; moderate pressure sustained for hours does more damage than brief high pressure.
Risk concentrates wherever soft tissue sits directly over bone with little padding: the sacrum, coccyx, heels, ischial tuberosities and, in patients positioned on their side, the greater trochanter and lateral malleolus. Immobility is the dominant risk factor, but it compounds with moisture from incontinence, friction from repositioning technique, poor perfusion and inadequate nutrition. A patient who is immobile and malnourished is not just additively at risk, the combination accelerates tissue breakdown faster than either factor alone.
How it presents — what you will actually see
Staging is based entirely on what is visible in the wound bed, which is why an accurate stage can only be assigned once you can see down to the deepest exposed tissue. Stage 1 is intact skin with non-blanchable erythema, often felt as warmth or firmness before it is seen as colour change, and it is the stage most easily missed on darker skin tones where erythema does not show the same way. Stage 2 is partial-thickness loss presenting as a shallow open ulcer or an intact or ruptured serum-filled blister, with a pink or red, moist wound bed and no slough.
Stage 3 is full-thickness tissue loss with visible subcutaneous fat but no exposed bone, tendon or muscle; slough may be present but does not obscure the depth of tissue loss. Stage 4 is full-thickness loss with exposed bone, tendon or muscle. An unstageable pressure injury is full-thickness loss where the wound base is obscured by slough or covered by eschar, so the true depth cannot be determined. That is the fact to hold onto: unstageable is not a severity category on its own, it is a temporary label that resolves into stage 3 or 4 once enough slough or eschar is removed to see the base.
Nursing assessment priorities
Assess every at-risk patient's skin on admission and at a set interval afterward, using a validated tool such as the Braden Scale to quantify risk from mobility, moisture, nutrition, friction and shear, and sensory perception. Pair the scale with a hands-on skin check of every bony prominence, because a numeric score can miss an early stage 1 injury that a visual and tactile check will not.
When a pressure injury is already present, assess location, size, wound bed tissue type, exudate amount and odour, periwound skin condition, and pain, and document using consistent terminology so the trajectory is traceable across shifts. If slough or eschar covers the base, document it as unstageable rather than guessing at a stage, and flag it for debridement assessment, since assigning stage 3 or 4 to a wound you cannot actually see is a documentation error that misleads the next clinician about depth. Reassess at every dressing change, not only at scheduled intervals, because exudate and tissue type can change faster than a fixed schedule captures.
Interventions and what to do first
The first action for any patient at risk or already affected is pressure redistribution: reposition at least every two hours, or more frequently based on tissue tolerance, and use a support surface appropriate to the risk level rather than relying on repositioning alone. For an existing injury, off-load the affected area completely wherever possible, for example floating heels rather than repositioning a patient who still bears weight on them intermittently.
Manage moisture separately from the wound itself, since incontinence-associated skin damage compounds pressure injury risk and is often mistaken for the injury progressing when it is really a second problem. Select dressings by wound bed characteristics rather than habit: moisture-retentive dressings for a clean granulating wound, and referral for debridement when slough or eschar is present, since that tissue has to come off before the wound can be accurately staged or before healing can proceed. Optimise nutrition alongside wound care, since protein and caloric deficits slow closure regardless of how well the wound itself is managed, and escalate to a wound care specialist or dietitian rather than managing a stage 3 or 4 injury on ward-level protocols alone.
Complications to watch for
Infection is the complication that changes the trajectory fastest: increasing periwound erythema, new or worsening odour, purulent exudate, or fever in a patient with a deep pressure injury warrants prompt reassessment rather than a routine dressing change. Osteomyelitis is a real risk with stage 4 injuries where bone is exposed, and a wound that fails to progress despite appropriate local care should raise that possibility.
Sepsis is the escalation to watch for in a frail or immunocompromised patient with an infected pressure injury, since systemic signs can appear subtly against a baseline of chronic illness. Watch also for undermining or tunnelling, where tissue destruction extends laterally under intact skin beyond what the surface wound suggests, since that changes wound measurement, packing technique and the overall prognosis for closure.
Patient teaching before discharge
Teach the patient and any home caregiver to check skin over bony prominences daily, particularly the sacrum, heels and any area that was previously affected, since skin that has broken down once is at higher risk of recurrence at the same site. Explain repositioning frequency in terms the patient can act on at home, whether that means a turning schedule, a pressure-relieving cushion for a wheelchair user, or heel protection during periods of bed rest.
Cover moisture management, especially for a patient managing incontinence at home, and be specific about the difference between a barrier product and a healing dressing so one is not substituted for the other. Reinforce the nutrition link plainly: adequate protein and calorie intake supports tissue repair, and a patient discharged with a healing pressure injury needs a concrete plan for maintaining that intake, not a general instruction to eat well. Give clear criteria for when to seek care again, such as increasing pain, new odour, drainage colour change or fever, so a developing complication is caught before it requires readmission.
The next step on this is the same as on everything else here: answer questions and read the rationales. Our med-surg practice questions are the closest set to what this page covers.
One question from the med-surg set
A client with chronic obstructive pulmonary disease has an oxygen saturation of 88% on 2 L/min via nasal cannula and is alert with no distress. What should the nurse do first?
Rationale
In COPD a saturation of 88–92% is the therapeutic target, not an emergency, and this client is alert with no distress. The first action is the independent nursing intervention that is least invasive and most likely to help: sit them up and reassess. Turning the oxygen up to 6 L/min risks blunting the hypoxic drive, and calling rapid response or drawing an ABG escalates ahead of an assessment you have not finished.
Answer: B
Common questions
What makes a pressure injury unstageable?
A pressure injury is unstageable when slough or eschar covers the wound base and hides how deep the tissue loss actually goes. It is not a separate severity level, it is a holding category, and it resolves into a stage 3 or stage 4 designation once enough of that covering tissue is removed to see the true depth.
How often should a patient at risk of pressure injuries be repositioned?
Every two hours is the standard baseline, but the actual frequency should be based on the patient's individual tissue tolerance, skin assessment findings and the support surface in use. A patient showing early non-blanchable erythema needs more frequent repositioning than the two-hour default, not less.
Can a stage 1 pressure injury be missed on darker skin?
Yes, and this is a well-recognised assessment gap. Non-blanchable erythema is the defining sign of stage 1, but on darker skin tones that colour change may not be visible, so warmth, firmness, oedema or a colour difference from surrounding skin become the signs to check for by touch rather than by sight alone.
What is the difference between a pressure injury and moisture-associated skin damage?
A pressure injury results from sustained pressure or shear over a bony prominence, while moisture-associated skin damage results from prolonged exposure to urine, stool or perspiration and tends to affect skin folds or perianal skin rather than bony prominences specifically. The two frequently coexist in an incontinent, immobile patient, but they need different interventions, and treating one as the other delays appropriate care.
Does debridement always happen before staging an unstageable wound?
Debridement is generally needed before an accurate stage 3 or 4 designation can be assigned, since the slough or eschar physically obscures the wound base. The decision on debridement method and timing sits with the wound care team based on the patient's overall condition, so the nursing role is to document the wound as unstageable and escalate for that assessment rather than delay reporting it.
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