According to the 2019 NPIAP guideline, pressure injuries are localized areas of injury to the skin or underlying soft tissue caused by sustained pressure or pressure in combination with shear or friction, including those related to a medical or other device. The tolerance of soft tissue for pressure and shear may also be affected by microclimate, nutrition, perfusion, comorbidities, and condition of the tissue. The injury can present as intact skin or an open ulcer and may be painful. Pressure injuries commonly develop in association with debilitating illness and injury that lead to immobility and gravity-dependent pressure over boney prominences, such as the sacrum, hip, heel, or ankle [1,3].

An estimated 95% of pressure injuries occur on the lower part of the body, with approximately 70% in the hip and buttocks area and 15% to 25% in the lower extremities [8]. There is a two to six times greater mortality risk for patients who develop pressure ulcers [8,9]. In acute care hospitals, patient risk for acquiring a pressure injury is estimated to range from 2.7% to 29% [1,8].

In 2014, the NPUAP (now the NPIAP) and the European Pressure Ulcer Advisory Panel (EPUAP) developed a common international definition and description system for pressure ulcers. As noted, the NPUAP further revised some of these definitions and staging efforts to reduce confusion and clarify terminology in 2019. The revised NPIAP guidelines for staging a pressure injury are [2,6]:

In 2014, the NPUAP (now the NPIAP) and the European Pressure Ulcer Advisory Panel (EPUAP) developed a common international definition and description system for pressure ulcers. As noted, the NPUAP further revised some of these definitions and staging efforts to reduce confusion and clarify terminology in 2019. The revised NPIAP guidelines for staging a pressure injury are [2,6]:

Health habits should be evaluated, including determination of how active the patient is, daily routines, diet, and sleep habits. Smoking, alcohol use, and illicit drug abuse can impair tissue profusion and delay wound healing [8,9].

A medication profile should be obtained, including prescription and over-the-counter medications. Certain medications will interfere with wound healing or interact with wound treatments [8,9]. For example, anti-inflammatory drugs can prolong the inflammatory phase of wound healing [12].

It is important to include a list of allergies in the medical history. For patients with latex allergy, wound care products that contain latex cannot be used. Sulfonamide antibiotics are common allergens, and silver sulfadiazine is a frequently used topical wound application. Before attempting any pharmacotherapy, the clinician must be aware of the patient's allergy history [9].

Many patients with asthma require steroid therapy to control and relieve symptoms, and it is not unusual for individuals with asthma to have a prolonged history of steroid use [9]. While steroids are effective in suppressing the inflammation responsible for asthma attacks, they also block the inflammatory phase of wound healing, which is essential to wound resolution [9]. Oral or topical vitamin A may be used to decrease the anti-inflammatory effects of steroids; consultation with the treating physician on an individual basis for the possible use of vitamin A in the wound treatment plan of care is recommended [14].

Approximately 10 to 13 million Americans are troubled with either transient or chronic urinary incontinence [15]. Urinary incontinence will lead to maceration (water logging) of the skin, potentiating the risk for further skin breakdown and contamination of existing wounds [9].

It is estimated that 11.6% of the American population has diabetes [16]. In these patients, elevated glucose levels can impair wound healing and negatively affect the immune system's ability to control infection. Wound healing in patients with diabetes is characterized by a decreased production and deposition of collagen and decreased strength of the healed tissue [1]. In addition, many patients with diabetes, particularly those whose disease is poorly controlled, will develop neuropathy, making the development of ulcers more likely and delaying healing.

Wounds should always be measured in centimeters, using a plastic or paper ruler. Wound length is measured from head to toe; width is measured from hip to hip. The depth of the wound can be obtained by gently inserting a sterile cotton-tipped applicator into the wound bed and marking it at skin level. The applicator is then measured using a metric ruler [1].

Sinus tracts and undermining impair healing, and it is important to immediately identify their presence. A sinus tract is a tunnel that extends from any part of the wound and can bore through subcutaneous tissue and muscle. This tunnel creates dead space, which can result in abscess formation and further impede the healing process. A sinus tract can be measured using a sterile cotton swab [13].

The condition of the surrounding skin surface up to 4 cm from the edge of the wound circumferentially must also be assessed and documented. Its characteristics should be noted, particularly color and integrity [14]. Maceration from excessive drainage may indicate that the dressing used is not appropriate and a different product is needed. Circumferential redness up to 2 cm from the wound is indicative of cellulitis.

According to the NPIAP, pressure injuries cause considerable pain and suffering [3]. Pressure ulcer pain has been described as ranging from sore to excruciating. In one study, 75% of patients rated their pain as mild, discomforting, or distressing; 18% rated their pain as horrible or excruciating [20]. Another study ranked pain according to stage of pressure ulcer and found that 50% of patients with stage 2 pressure ulcers indicated their pain was discomforting. All patients with stage 3 ulcers indicated pain was distressing, and 100% of patients with stage 4 injuries rated pain as horrible [21]. Pain and odor control are a major concern for patients, and studies have shown that patients rank pain control as more important than healing [13]. The level of pressure ulcer pain depends both on the stage of the ulcer and on manipulation of the area (e.g., if a dressing change is done at the time of assessment). The majority of patients report pressure ulcer pain at rest as well as with dressing changes. Pressure ulcer pain may be due to tissue trauma, inflammation, damaged nerve endings, infection, procedures such as debridement, and dressing changes [21].

The criterion standard for assessing pain intensity is self-report using standard pain intensity instruments. Two of the most widely used pain assessment scales are the numeric pain intensity scale and the Wong-Baker Faces Pain Rating Scale [22]. The numeric pain intensity scale consists of ratings from 0 (no pain) to 10 (worst possible pain). This scale can be used for pain assessment with adults and children older than 7 years of age [6]. Visual presentation of the numeric pain intensity scale is helpful with hearing impaired patients, and the scale has been translated into many languages.

Wounds can also be described as healing by primary or secondary intention. Wounds resolved by primary intention are surgically closed. With secondary intention, wounds are left open and heal via the process of granulation, contraction, and epithelialization. Pressure injuries are an example of a wound that heals by secondary intention. A third classification, wounds that heal by tertiary intention, includes cases in which healing starts by secondary intention but the wound is then surgically closed [14]. Wound healing can be conceptualized as a cascade of events, and the process will differ depending on many different factors, particularly whether the wound is partial thickness or full thickness [14]. A partial thickness wound involves loss of the epidermis and usually part of the dermis [1]. These wounds are shallow, superficial, and painful. Healing of a partial thickness wound is usually a straight-forward process involving a brief inflammatory phase, cell migration, and re-establishment of normal skin layers [14]. The most important consideration with partial thickness wounds is to keep the area moist and clean. It is important to remember that a dry cell is a dead cell.

Full thickness wounds occur when there is destruction of the epidermis and the complete dermis. At the base of the wound, subcutaneous tissue, fascia, muscle, or bone may be visible [14]. Healing of full thickness wounds occurs in four stages: hemostasis, inflammation, proliferation, and remodeling, with considerable overlap occurring among the stages. The time frame for repair of a full thickness wound is considerably longer than that of a partial thickness wound [1]. Regardless of the cause, this biologic process of repair is the same for all acute wounds [9].

The proliferative phase of wound healing overlaps and follows the inflammatory phase. During this process, the wound bed is filled with new granulation tissue and the wound is resurfaced with new epithelial tissue [14]. This stage can last for several weeks [9].

The Institute for Clinical Systems Improvement (ICSI) recommends that all pressure ulcers be cleaned when first diagnosed and then with every dressing change [23,24]. The purpose of wound cleaning is to remove nonadherent debris from the wound bed in order to promote healing and make the wound less susceptible to bacterial overgrowth and infection [13]. While cleaning the wound, it is necessary to minimize trauma to the wound bed and healthy tissue [13]. Choosing the correct product for cleaning the wound is very important. Most wounds can be effectively cleaned with normal saline, a nontoxic and inexpensive product [9,24]. If used, saline must be applied to the wound with sufficient force to remove surface debris and contaminants while also minimizing trauma to the wound [1]. Normal saline used for wound cleansing should be room temperature and should be discarded within 24 to 48 hours after opening [9].

Enzyme formulations available for debridement include collagenase (Santyl), papain (enzymes derived from papaya), and trypsin (Granulex, Vasolex, Xemaderm); only collagenase is available in the United States [12]. Collagenase is a derivative of Clostridium bacteria and acts by liquefying the collagen bonds that fasten necrotic tissue to the underlying wound bed. The time to effect ranges from several days to weeks.

Hydrogel dressings are used with shallow wounds with minimal amounts of drainage and are also a good option for painful ulcers [6]. Hydrogel dressings are usually hydrating and are either glycerin- or water-based [1]. These dressings are appropriate for use with topical medications and antibacterial agents [13].

For nonhealing wounds, the first factor to evaluate is the quality of wound care. This includes determining if dressing changes are being carried out at the recommended intervals, if the dressings are applied appropriately, and if the manufacturer's instructions for product use are being followed [1]. Factors affecting the patient's condition should be taken into consideration and addressed appropriately. Failure of a wound to improve is often due to systemic factors, such as ischemia, infection, or malnutrition, or continuation of the causative factors. These issues must be addressed first to achieve optimum wound healing. A change in the dressing treatment is indicated if any of the following problems occur [14]: