#34574: Treating Pressure Injuries and Chronic Wounds

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 addition to the revised staging definitions, the NPIAP Consensus Conference members agreed upon two new pressure injury definitions [2]:

A detailed history is usually gathered during an interview with the patient, significant others, family, caregivers, and other healthcare professionals involved in the patient's care. If a patient is admitted from another facility, it may be necessary to speak with the nursing staff at that facility in addition to reviewing the medical record.

The patient interview should be conducted in a private, quiet area and in an unhurried manner. One goal of the interview process is to begin to develop the therapeutic relationship with patients and those who are important in their care. The interview should not be merely a series of questions but should also include active listening and observation [9].

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].

The physical examination will include a systems review, and the clinician must assess how impairments in any body system will impact wound healing and help shape the plan of care [8]. Comorbid conditions play a part in this assessment. Diabetes and obesity, specifically, affect a large number of patients and can result in devastating impairment in wound healing.

A full nutritional assessment and plan, preferably in consultation with a nutritionist, is an important part of wound care, as nutritionally compromised patients have greater difficulty achieving wound healing. The goal is to characterize the patient's current nutritional state, identify changes that have occurred in recent months or weeks, and predict the impact on the patient's overall functional level and prognosis for healing. This assessment should include protein and calorie intake, hydration status, and the measure of serum albumin and/or proalbumin. Dehydration impairs wound healing by decreasing the blood volume available to transport oxygen and nutrients to healing wounds [9].

Once the patient's nutritional needs and functional status have been clarified, an appropriate plan of care can be devised to ensure adequate nutritional and fluid intake. For some patients with late-stage pressure ulcers and documented nutritional deficiencies, a brief period of enteral or parenteral supplementation may be advisable, keeping in mind that the patient's and family's preferences play an important role in establishing a diet plan.

At the end of the interview and physical examination of the wound(s), it should be possible to formulate goals and develop a plan of care as a team, including the patient and family [9]. Clinicians should be aware that a completely healed wound may not be an attainable goal for all patients. For example, an appropriate goal for a hospice patient might be for the wound to remain stable and for wound pain and odor to be adequately controlled.

It may also be necessary to set separate short-term and long-term goals for wound care. The short-term goals are those that would be implemented immediately in the acute care setting, while long-term goals would continue after discharge [9].

Aside from the physical condition of the wound, information about the history of the wound should be obtained. How the wound started and how long it has been present must be documented. Treatments used and the patient's wound response to these interventions should also be noted [9]. If noncompliance with treatments has been an issue, the underlying cause(s) must be ascertained. Lack of communication between the involved parties may have led to a misunderstanding on the part of the patient and/or caregiver(s) as to their role in wound care. For example, a bedbound patient in the home may require daily dressing changes by the designated family caretaker, with the home health agency monitoring wound progress on a weekly basis. To prevent inadequate care, the caretaker should be appropriately trained in the dressing technique and should understand the importance of completing the dressing changes on a daily basis. Economic strain can also contribute to noncompliance. Patients may not have the financial resources necessary to purchase dressing supplies.

With the growing awareness of the possibility of litigation in wound care, many facilities have instigated a policy of photo documentation. Wounds present on admission are photographed. In addition, some facilities require serial photographs to track wound progress and status at the time of discharge. Signed consent is required before wound photographs can be taken, and in most instances, the photographs become a permanent part of the patient's medical record. Approximately 75% of home health agencies in the United States now include wound photography as part of the patient's medical record [9]. The American Health Information Management Association recommends that consent for photography be included in the consent for treatment when photography is routinely used. The Health Insurance Portability and Accountability Act (HIPAA) guidelines require that patients are adequately informed of the use of photography [18].

Accurate measurement of the wound is probably the most important feature of wound assessment [9]. It provides information on the initial size and progression or non-progression of healing, allowing for valuable feedback on the effectiveness of clinical interventions. Decreasing wound size is generally regarded as a sign of wound healing [13].

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].

Undermining is defined as destruction of the tissue under the skin around the edges of the wound. This frequently occurs in pressure ulcers that have been subjected to shear force as well as pressure. It is important to document the location and extent of undermining.

The easiest way to measure and describe undermining is by using the face of the clock. With the patient's head representing 12 o'clock, sweep the area of undermining or probe the tunneling to ascertain the depth. For example, undermining along the right border would be recorded as extending from 1 o'clock to 5 o'clock with a depth of 4 cm [13]. It is important to check around the entire perimeter of the wound, as undermining can occur in more than one location.

It is also vital to assess and document the appearance of the wound bed. If the wound bed has a mixture of tissue in it, this should be documented by an approximate percentage (e.g., the wound base is 75% granulation tissue and 25% slough). Granulation results in "beefy" red tissue with a shiny, moist granular appearance, while necrotic tissue is gray, brown, or black. Eschars are typically gray to black and dry or leathery in appearance [19]. Slough tissue is yellow/white to gray in color. It may be stringy or thick and appear as a layer over the wound bed [19]. Epithelial tissue will often begin to grow in from the edges over the wound surface. This tissue is generally pink and shiny. As a quick reference color guide, red is associated with normal healing, yellow indicates slough or dead tissue, and black is necrosis [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.

The Wong-Baker Faces Pain Rating Scale consists of six faces ranging from a happy smiling face (no pain), to a crying, frowning face (worst pain). The patient is asked to choose the face that best reflects his or her pain. The Faces Pain Rating Scale is the preferred scale for use with children and may also be used with the geriatric population. It can also be used with cognitively impaired patients and those for whom English is a second language.

After the initial pain assessment has been completed, reassessment should be done at regular intervals. As noted, pain intensity should be rated by the patient, not a healthcare professional. The following questions may be used to help determine patients' pain levels:

Hemostasis begins soon after a wound develops. This stage involves fibrin clot formation to stem blood loss and to protect the wound from bacterial infection. Studies have shown that substandard clot formation leads to poor wound healing, and individuals with impaired clotting have impaired healing [1,14]. Clotting activates degranulation of the platelets, which causes the release of growth factors called polypeptides into the wound [9]. Growth factors begin the process of wound repair by recruiting neutrophils and macrophages to the wound bed [14].

The standard signs and symptoms of localized inflammation are erythema, swelling, warmth, and tenderness. In normal healing, these signs are only minimally noticeable. During the inflammatory phase of wound healing, they are considered a normal response [9].

After hemostasis is established, the next stage in the process of natural healing is inflammation, which should result in the establishment of a clean wound bed. During this phase, damaged tissue is broken down and, along with excessive bacteria, removed from the wound by white blood cells [1]. The two most important cells involved in the inflammatory phase are neutrophils and macrophages [13].

Neutrophils arrive in the wound immediately after injury, usually within the first hour. For the first few days they lead the wound clean-up process [1]. They target the bacteria and debris in the wound, which is removed by the process of phagocytosis. Neutrophils have a very short life span, and around the third day after injury, they begin to disappear from the wound and are replaced by macrophages [13].

Macrophages perform multiple functions in wound repair and have been referred to as the regulators of wound repair. They are essential to the process of moving wound healing from the inflammatory phase to the proliferative phase [9]. Studies have shown that wound repair is limited or non-existent in the absence of macrophages [14].

When caring for a wound in the inflammatory phase, the goals are debridement and infection control. These wounds usually have a great deal of drainage, so absorptive dressings are normally used [14]. The end result of the inflammatory phase is a clean wound bed [1].

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].

In full thickness wounds, the process of re-epithelialization occurs only from the wound edges [14]. Margin basal cells attached to the dermis eventually loosen and start migrating across the wound. The horizontal movement comes to a halt when the cells meet [9]. This is called contact inhibition. Wound contraction is the final part of the proliferative phase. Fibers in the wound contract to bring the wound edges closer together.

Maturation and remodeling of the wound involves rearranging collagen fibers and increasing the tensile strength of the scar tissue. Scar tissue regains about 80% of normal tissue strength within three months, but it is important to note that it never achieves the full strength of the original tissue [14]. Therefore, the healed site of an old wound is vulnerable to further breakdown.

The body's own physiologic processes to remove necrotic tissue are referred to as autolytic debridement [9]. Studies have shown that autolytic wound debridement is more effective than wet-to-dry dressings because it removes only necrotic tissue and leaves healthy tissue intact [9]. For autolytic debridement to be successful there must be a moist environment and sufficient white blood cells available to the wound [1]. A layer of wound exudate should be kept in contact with the surface of the wound [14]. A moisture-retaining dressing may be used to keep the wound bed moist [9,13]. This allows fluid to accumulate in the wound, rehydrating necrotic tissue and making it possible for enzymes in the wound to digest the dead tissue [9]. For a wound covered with dry eschar, it is appropriate to crosshatch the eschar, as this allows a faster build-up of moisture in the wound [9]. In their clinical practice guidelines for pressure ulcer treatment, the ICSI recommends autolytic and enzymatic debridement as the preferred approach for patients in long-term care and home care and for patients who cannot tolerate other methods of debridement [9,23].

Choosing the correct product and dressing material for autolytic debridement is important to successful healing; a semi-occlusive or occlusive dressing should be used [13]. In addition, amorphous hydrogels are effective in digesting necrotic tissue in wounds and may be used as an adjunct [9].

Transparent film dressings are the best choices for debriding dry eschar, as they are non-absorptive. These dressings establish a fluid environment. For moist wounds with necrotic tissue, hydrocolloids are a good choice. Hydrocolloids have the ability to absorb a certain amount of drainage while maintaining a moist wound environment [9].

There are several advantages to autolytic debridement. It is relatively inexpensive and harmless to healthy tissue. Wound progress is usually seen within six days, and it can be used in combination with other debridement methods for enhanced effect [9]. It is generally a good option for patients whose condition does not permit surgical intervention.

The disadvantage of the autolytic approach is that lack of familiarity with the process can cause problems. The breakdown of dead tissue and the subsequent odor and accumulation of exudate may cause clinicians/family members to wrongly infer that the wound is either infected or worsening [1].

Nursing staff and caregivers should understand that the accumulated fluid in the wound contains essential factors necessary for debriding the wound and promoting wound repair [1]. Education should also note that the wound will initially become larger with debridement, but this is not a sign that the wound is deteriorating [13].

Enzymatic debridement is a safe and effective method that involves the application of a concentrated, commercially prepared enzyme to the surface of the necrotic tissue [13]. It is recommended when surgical debridement is not an option and the patient is not considered a good candidate for autolytic debridement [9,23].

Enzymatic debridement is a selective method that will not adversely affect healthy tissue [9]. Applied enzymes liquefy the necrotic tissue and destroy the bonds that attach it to the wound bed [12]. The advantages of enzymatic debridement are that it does not harm healthy tissue in the wound and can be effectively used in combination with other methods of debridement [9]. Eschar present in the wound should be crosshatched before application of enzymatic therapy to improve efficacy, as enzymes are not active on a dry surface [9].

Wound progress should be seen in 48 to 72 hours. However, complete debridement of the wound may be a long process; therefore, whenever possible this method is used in conjunction with autolytic debridement and conservative surgical wound debridement (i.e., bedside removal of loosely adherent necrotic tissue) [14]. Conservative surgical wound debridement is completed by a physician or a wound care nurse.

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.

Enzymatic debridement can be used in conjunction with most other dressings; however, it should not be used with silver or cadexomer iodine dressings. Silver dressings reduce the efficacy of collagenase by more than 50%; cadexomer iodine reduces its efficacy by 90% [28].

Studies indicate that enzymatic debridement is cost-effective, but it requires daily or twice daily dressing changes and the application of a secondary cover dressing, which should be factored into the cost [28]. When the wound bed is free from necrotic tissue and slough, the use of enzymatic debridement should be discontinued.

Enzymatic debridement is not generally indicated for the treatment of infected wounds due to the extended length of time required to achieve a clean wound. If necessary, enzymes may be used in cases of infected wounds if antibiotic therapy has already been initiated [14].

Mechanical debridement is achieved by applying outside force to remove necrotic tissue in a wound [9,23]. One long-standing and widely used form of mechanical debridement is wet-to-dry gauze dressings, usually with normal saline. Although it is a commonly used treatment, the advantages of familiarity and simplicity of use are outweighed by the disadvantages. Studies indicate that wet-to-dry dressings remove healthy viable tissue as well as necrotic tissue [9]. In addition, the standard time frame for dressing changes, every eight hours, increases the associated costs of labor and supplies. The dry, adherent dressings are painful to remove, and seepage of moisture from the dressing can lead to maceration of periwound tissue. As such, the AHRQ advises cautious use of this method of debridement [9].

Whirlpool therapy is another form of mechanical debridement. It is most frequently used with larger wounds to remove debris and bacteria from the wound bed. However, it does not remove dry eschar from the wound, and there are concerns about the likelihood of cross-contamination between patients [1].

The use of ultrasound waves to debride wounds has also been explored. With this technique, low-frequency ultrasound creates small bubbles in the wound that implode, causing the necrotic tissue to liquefy [12]. This method is generally less painful and less traumatic than traditional methods, with faster healing rates compared to other methods of mechanical debridement [29,30]. Studies show that low-frequency ultrasound is most effective when used three times per week [30]. However, further comparative evidence and large-scale studies are necessary before it can be recommended as a replacement for established treatment modalities [30,31].

Chemical debridement utilizes nonenzymatic solutions to break down necrotic tissue in wounds [14]. The most widely used are sodium hypochlorite (bleach) solutions, including Dakin's solution, and oxychlorosene (Clorpactin WCS-90) [14,36,37]. Dakin's solution at the strength of 0.25% is nontoxic to healthy tissue, and gauze dressings soaked in Dakin's solution help to dissolve necrotic tissue and decrease the bacterial burden in the wound [14]. Regardless of the chemical used, the dressings must be changed every 12 hours. The periwound area should be protected from contact with the dressing, either with petrolatum ointment or strips of solid skin barrier around the edges of the wound [14].

Dakin's solution is normally stored in clear containers. It loses its potency in 24 to 48 hours and must be replaced at least every other day. When first opened, containers should be labeled with the date and time. After the wound is free from necrotic tissue, the use of sodium hypochlorite or oxychlorosene should be discontinued [14].

The National Pressure Injury Advisory Panel, the European Pressure Ulcer Advisory Panel, and the Pan Pacific Pressure Injury Alliance recommend using hydrocolloid dressings for non-infected category/stage 2 pressure injuries, as indicated by the clinical condition of the pressure injury.

(https://static1.squarespace.com/static/6479484083027f25a6246fcb/t/6553d3440e18d57a550c4e7e/1699992399539/CPG2019edition-digital-Nov2023version.pdf Last Accessed: July 18, 2024)

Level of Evidence: B1 (The recommendation is supported by level 1 studies of moderate or low quality providing direct evidence or level 2 studies of high or moderate quality providing direct evidence.)

Hydrocolloids are excellent dressings for the prevention of secondary infections [14]. In the past, hydrocolloids were considered occlusive dressings, but more recent versions have a backing of a semiocclusive film layer that is impermeable to fluids and bacteria but semipermeable to gas and water vapor [1]. Hydrocolloids can accommodate only moderate amounts of wound drainage and are therefore not used for heavily draining wounds [14].

These dressings can produce an odor upon removal. In the absence of other signs of clinical infection, this is not an abnormal finding and should be explained to concerned patients and staff [13]. Hydrocolloids may also leave a residual in the wound bed, which should be gently irrigated out at dressing change. Hydrocolloids lose their effectiveness if they are changed too frequently and should not be used for wounds that need to be monitored daily [1].

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].

Amorphous hydrogel dressings are especially useful for wounds with depth and contours [6]. However, these dressings provide only minimal absorption and should be used in wounds with small amounts of exudate [14]. Amorphous hydrogel dressings vary widely in their level of viscosity and are available in sheet dressing, tube, spray bottle, and ribbon gauze [1].

Foam dressings are a good choice for stage 2 and shallow stage 3 injuries with drainage and for painful pressure injuries. Foam dressings protect wounds at risk of further damage from shear and can be used along with topical treatments [6,13]. Foam dressings impregnated with ionic silver are available to reduce the risk of infection. These dressings can also be used along with alginates to improve management of wound drainage [1]. Foam provides for thermal insulation, conforms to body shape, and leaves no residual in the wound [9]. Clinicians must be careful to place the correct side of the foam dressing in contact with the wound surface [13].

Silver-impregnated dressings are a treatment option for infected or heavily colonized wounds or wounds that are at increased risk for infection. Silver has an antimicrobial effect on a broad spectrum of organisms and has been shown to reduce the bacterial count in wounds, except for highly exuding wounds where the cytotoxic properties of silver may offset these advantages [1,38]. Sustained-release silver dressings are toxic to bacteria and fungi but do not adversely affect healthy wound tissue [14]. However, silver-resistant organisms do exist, and the judicious use of silver is advised, similar to the approach adopted with antibiotics [1,38]. It is recommended that the use of silver dressings be limited to a two- to four-week period [1].

Cadexomer iodine dressings are used for wounds with moderate-to-high amounts of drainage. They should not be used for patients who are sensitive to iodine or individuals with thyroid disease [39]. Cadexomer iodine dressings are antimicrobial and help fight bacteria while maintaining a moist environment for wound healing [13]. Although these dressings are capable of reducing bacterial counts in wounds, they do not replace the need for systemic antibiotic therapy and are regarded as an adjunct in the treatment of wound infections [13]. One systematic review found no clear difference between cadexomer iodine and standard care [40].

Calcium alginate dressings are highly absorptive dressings made from lightweight seaweed. They can absorb up to 20 times their weight in wound drainage, which makes them an excellent choice for heavily draining wounds [13]. There are two types of alginates: one that becomes a gel after coming in contact with the wound drainage and one that retains its original shape while absorbing exudates [14]. In addition to their absorptive abilities, calcium alginate dressings can aid in hemostasis, making them a good choice for bleeding wounds. They also have been found to be effective against both Gram-positive and Gram-negative bacteria [41]. Wounds treated with alginate dressings made from seaweed may smell fishy or like "low tide" [13].

Hydrocolloid fiber dressings are used only in wounds with large amounts of drainage. They are placed in the wound dry and transform into a gel after absorbing exudate [14]. These dressings are comfortable and easy to remove, but they usually require a secondary dressing to hold them in place [13].

Gauze packing was used frequently in the past, but it is now regarded as less effective in coping with wound drainage than calcium alginate or hydrocolloid fiber dressings. Gauze dressings do not provide a barrier against bacteria, do not lower wound temperature, and can pull healthy granulating tissue out of the wound on removal [14]. Gauze dressings are also labor intensive, requiring several dressing changes daily, which adds to the cost of the overall care [13].

Composite dressings are a combination of more than one material used to fulfill several important functions in the wound. They provide an effective barrier to bacterial contamination of the wound and include an absorptive layer and foam, hydrocolloid, or hydrogel. Composite dressings can have either a semi-adherent or non-adherent surface placed in contact with the wound bed [13]. Composite dressings are comfortable and are available in various shapes and sizes [1]. These dressings should not be cut, as this compromises the structure of the dressing [13].

Some dressings incorporate collagen, which is an important protein involved in wound healing and repair [1]. The dressings can be 100% collagen or combined with other products, such as alginates. They provide a high level of absorption while keeping the wound bed moist and are easily removed [13]. For wounds with very little drainage, collagen gel can be applied in a layer one-quarter inch thick [1]. Collagen used in most wound dressings is derived from cowhide. Therefore, it should not be used in patients who are allergic to bovine products [13].

Wound care documentation should be concise and frequent [13]. It should be based on nationally recognized standards of care; shortcuts should not be used, and only approved abbreviations should be included in the documentation [12]. Problems arise when there are numerous and different descriptions of a pressure injury [1]. If present, all wounds should be documented on admission to provide a baseline comparison for future assessments [13]. Subsequent wound care provided must be recorded, including accurate dates and times and the name of the clinician providing the care. All statements should be substantiated by objective clinical findings. The condition of the wound on discharge should be thoroughly documented and reported to the agency providing follow-up care. As noted, photography is becoming increasingly commonplace.