WOUND CARE ESSENTIALS

Practice Principles
Sharon Baranoski & Elizabeth A. Ayello

Chapter
13 PRESSURE ULCERS

Dr Fatima Amjad PT
Pressure Ulcers
• A pressure ulcer is a localized injury to the skin and/or underlying tissue usually
over a bony prominence, as a result of pressure, or pressure in combination with
shear.
• Over the centuries, pressure ulcers have been referred to as decubitus ulcers,
bedsores, and pressure sores. The term pressure ulcer has become the preferred
name because it most closely describes the etiology and resultant ulcer.
• Pressure ulcers are usually located over bony prominences (such as the sacrum,
coccyx, hips, heels) and are classified according to the extent of the type of
observable tissue damage.
International NPUAP/EPUAP/PPPIA
Pressure Ulcer Classification System
• Category/Stage I: Nonblanchable Erythema
• Category/Stage II: Partial-Thickness Skin Loss
• Category/Stage III: Full-Thickness Skin Loss
• Category/Stage IV: Full-Thickness Tissue Loss
• Unstageable: Depth Unknown
• Suspected Deep Tissue Injury: Depth Unknown
Stage I
• Intact skin with non-blanchable redness of a localized area, usually over a bony
prominence, signals Stage I.
• Darkly pigmented skin may not have visible blanching; its color may differ from
the surrounding area.
• The area may be painful, firm, soft, and warmer or cooler compared to adjacent
tissue.
• Stage I may be difficult to detect in individuals with dark skin tones. May indicate
“at risk” persons (be a heralding sign of risk).
STAGE II
• Stage II is characterized by partial-thickness loss of dermis presenting as a shallow
open ulcer with a red to pink wound bed, without slough.
• Stage II may also present as an intact or open (ruptured) serum-filled blister.
• Presents as a shiny or dry shallow ulcer without slough or bruising. (Recall that
bruising indicates suspected deep tissue injury.
• This stage should not be used to describe skin tears, tape burns, perineal
dermatitis, maceration, or excoriation.
STAGE III
• Full-thickness tissue loss signals Stage III. Subcutaneous fat may be visible but
bone, tendon, or muscle are not exposed
• Slough may be present but it does not obscure the depth of tissue loss.
• Stage III may include undermining and tunneling.
• The depth of a Stage III pressure ulcer varies by anatomic location.
• The bridge of the nose, ear, occiput, and malleolus do not have subcutaneous
tissue and Stage III ulcers can be shallow.
• In contrast, areas of significant adiposity can develop extremely deep stage III
pressure ulcers.
• Bone and tendon is not visible or directly palpable.
STAGE IV
• Stage IV is characterized by full-thickness tissue loss with exposed bone, tendon,
or muscle.
• Slough or eschar may be present on some parts of the wound bed.
• Stage IV often includes undermining and tunneling.
• The depth of a Stage IV pressure ulcer varies by anatomic location.
• The bridge of the nose, ear, occiput, and malleolus do not have subcutaneous
tissue and these ulcers can be shallow.
• Stage IV ulcers can extend into muscle and/or supporting structures (e.g., fascia,
tendon. joint capsule) making osteomyelitis possible.
• Exposed bone/tendon is visible or directly palpable.
Unstageable
• The wound is classified as unstageable when it exhibits
a full-thickness tissue loss in which the base of the ulcer
is covered by slough (yellow, tan, gray, green, or brown)
and/or eschar (tan, brown, or black) in the wound bed
• Until enough slough and/or eschar is removed to
expose the base of the wound, the true depth, and
therefore stage, cannot be determined.
• Stable eschar (dry, adherent, intact without erythema)
on the heels serves as “the body’s natural (biologic)
cover” and should not be removed.
Suspected Deep Tissue Injury
• Deep tissue injury is characterized by a localized area of
discolored intact skin (purple or maroon) or a blood-filled
blister, due to damage of underlying soft tissue from
pressure and/or shear.
• The area may be preceded by tissue that is painful, firm,
mushy, boggy, and warmer or cooler compared to
adjacent tissue.
• Deep tissue injury may be difficult to detect in individuals
with dark skin tones.
• Evolution may include a thin blister over a dark wound
bed.
• The wound may further evolve and become covered by
thin eschar.
• Evolution may be rapid, exposing additional layers of
tissue even with optimal treatment.
Wound Etiology
• pressure ulcer development caused by pressure-induced capillary closure cutting
off blood supply leading to tissue ischemia, injury, and death. More recent, cellular
distortion and damage from pressure due to mechanical loading and deformation
of soft tissues near bony prominences.
• The recent international NPUAP/EPUAP/PPPIA clinical practice guideline states
that “pressure ulcers develop as a result of the internal response to external
mechanical load.”
• It involves the interplay of mechanical loading and an individual’s tissue tolerance.
Pressure Gradient
• The pressure gradient has been used to explain how pressure translates into tissue
death.
• External pressure is transmitted from the epidermis inward toward the bone as well
as by counter-pressure from the bone. As a result, the loaded soft tissues, including
skin and deeper tissues (adipose tissue, connective tissue, and muscle), will deform,
resulting in strain and stress within the tissues.
• Body tissues differ in their ability to tolerate pressure.
• The blood supply to the skin originates in the underlying muscle. Muscle is more
sensitive to pressure damage than skin tissue.
• Tissue tolerance is further compromised by extrinsic and intrinsic factors.
• Extrinsic factors as to the role they may play in pressure ulcer development
include moisture, and temperature, and are usually collectively referred to as
microclimate.
• Another intrinsic factor, tissue perfusion (or lack thereof), and the resulting
ischemia may be another important part of explaining how pressure ulcers occur.
Primary Independent Predictors
• Mobility/ activity
• Tissue perfusion
• Skin/Pressure status
• Activity and mobility limitations create the necessary conditions for pressure
ulcers to develop (i.e., unrelieved pressure). Individuals who are bedbound,
chairfast, and unable to effectively reposition themselves fall into these risk factor
categories and should be considered at risk.
Forces that affect tissue
• Shear has the potential to damage deeper tissue.
• Shear and friction are two separate phenomena, yet they often work together to
create tissue ischemia and ulcer development.
• Friction is a force that is parallel to the skin surface and may damage the
epidermis causing blisters but not pressure ulcers. The tissue injury resulting from
friction may look like a superficial skin insult.
• Shear (shear stress) is “the force per unit area exerted parallel to the plane of
interest” while shear strain is the “distortion or deformation of tissue as a result of
shear stress.”
• This insult and compromise to the blood supply create ischemia, reperfusion injury, lymphatic
impairment, and mechanical deformation of tissue cell and lead to cellular death and tissue
necrosis. Shear and friction go hand in hand—you’ll rarely see one without the other.
Practice Point
• You won’t see shear injury initially at the skin level because it occurs underneath
the skin. You will see friction injury. Elevation of the head of the bed increases
shear injury in the deep tissue and may account for the number of sacral ulcers we
see in practice.
Location of Pressure Ulcers
• Most pressure ulcers occur in the lower part of the body over bony prominences such
as the sacrum, coccyx, ischial tuberosities, greater trochanters, heels, iliac crests, and
lateral and medial malleoli.
• Other areas, where pressure ulcers may be overlooked, include the occiput (especially
in infants and toddlers, Pressure ulcers in neonatal and pediatric populations),
elbows, scapulae, and ears (especially in patients using nasal oxygen cannulas).
Common Site for Development
• Most common site is sacrum for pressure ulcers and heels being second.
• The incidence of heel ulcers has increased incrementally over the past decade,
creating a need for prevention protocols targeting the heels. The HEELS©
mnemonic can be used to care for heels at risk for pressure ulcers.
Pressure ulcers caused by Medical Devices
• Ear is common site for pressure ulcers.
• Devices that are commonly associated with pressure ulcers include respiratory
devices such as
• oxygen tubing (ears),
• nasotracheal tubes (ET, mouth and lips),
• continuous positive airway pressure (CPAP) masks, and biphasic positive airway pressure
(Bi-PAP) (bridge of nose, face);
• Orthopedic devices including
• cervical collars (neck and head)
• halo devices
• external fixators
• Any tube under pressure can create pressure damage.
Prevention
Preventing pressure ulcers is of vital importance. Elements of pressure ulcer
prevention include
• identifying individuals at risk for developing pressure ulcers
• preserving skin integrity
• treating the underlying causes of the ulcer
• relieving pressure
• paying attention to the total state of the patient to correct any deficiencies
• educating the patient and his or her family about pressure ulcers
Risk Factor Assessment
• Braden Scale most commonly used pressure ulcer assessment tool
• The Braden Scale has six subscales:
• sensory perception
• moisture
• activity
• mobility
• nutrition
• friction/shear
• The scale is based on the two primary etiologic factors of pressure ulcer development—
intensity and duration of pressure and tissue tolerance for pressure.
• “Sensory perception, mobility, and activity address clinical situations that predispose a
patient to intense and prolonged pressure, while moisture, nutrition, and friction/shear
address clinical situations that alter tissue tolerance for pressure.
Pressure Ulcer Treatment
• The comprehensive local management of pressure ulcers includes
• cleaning, controlling infections, debridement, dressings that promote a moist
wound environment (if a healable wound), nutritional support, and redistribution
of pressure (repositioning and use of support surfaces).
Monitoring Healing
• Several instruments have been developed and validated to assess the healing of
pressure ulcers.
• Bates-Jensen Wound Assessment Tool (BWAT)
• Pressure Ulcer Scale for Healing (PUSH)
• uses only three variables—surface area (length and width), exudate amount, and
tissue appearance—to derive a numerical indicator of the status of the pressure
ulcer.
Principles of Local Wound Care
• Cleansing
• Debridement
• Pressure redistribution
• Dressings
• Nutrition
• Control of infections
• Adjunctive Therapies
THANK YOU