Dr. Walker has provided a comprehensive overview of the problem of pressure ulcers, with appropriate adaptation to cancer patients. Cancer patients are frequently at high risk of developing pressure ulcers, especially late in the disease process; yet, this topic is infrequently addressed.
As Dr. Walker has noted, the best way to manage pressure ulcers is to prevent them, and the keys to prevention are prompt identification of patients at risk and immediate and consistent implementation of preventive measures. Patients who remain ambulatory are generally at low risk and do not require risk assessment; most clinicians suggest, however, that any patient who is chair- or bedbound undergo routine risk assessment. Use of a structured risk-assessment tool (eg, the Braden scale) permits accurate identification of high-risk patients and timely implementation of a prevention program.
The most important preventive strategies, as Dr. Walker states, are routine repositioning and appropriate use of support surfaces. The many support surfaces available can be grouped into two major therapeutic "groups." The least expensive products are mattress overlays and static pressure-reducing mattresses. These products are generally appropriate for patients who can assist with turning and who have at least two intact turning surfaces. The second group of products comprises rental mattresses or beds. These usually feature dynamic air support with low-shear and low-friction surfaces. They are indicated for patients who are immobile, have breakdown of more than one turning surface, or experience pain with turning.
Routine repositioning is the keystone of any effective pressure ulcer prevention program. When turning causes pain, beneficial strategies include the use of turn sheets and a 30° "tilt" from supine, as opposed to a full turn. (As Dr. Walker points out, a 30° tilt also avoids positioning directly onto the trochanters.) Repositioning should include elevation of the heels (with commercial products or pillows) when the patient is supine, because the heels are a particularly vulnerable area.
Dr. Walker’s comments regarding doughnut-type devices are of particular importance. Although these devices "appear" to relieve pressure, they actually compromise arterial inflow and venous drainage of the affected area and are always contraindicated. Moreover, his comments regarding massage are equally appropriate and represent an important component of education for the lay caregiver, who has probably heard about the "beneficial effects" of massage.
Staging and Treatment
Dr. Walker has accurately identified some of the problems associated with the current staging system. Although tremendous emphasis is frequently placed on ulcer stage, the parameters that reflect progress in healing and that direct topical therapy include wound dimensions and depth, extent of undermining or sinus tract formation, status of the wound bed (granulating vs necrotic), and signs of infection. These are the assessment parameters that should be emphasized.
In regard to treatment, the author appropriately focuses initially on correction of the causative factors. (Many clinicians begin with a focus on topical therapy.) I would also suggest making a conscious decision, whenever an ulcer is identified, as to the goals of treatment. As Dr. Walker correctly points out in his conclusion, healing may be impossible due to the patient’s general status, or the care required to promote healing may conflict with comfort goals. In general, wounds are very unlikely to heal if the underlying cause cannot be eliminated (eg, if the patient cannot be effectively positioned off the area) or if the patient is nutritionally compromised (ie, in a catabolic state as opposed to an anabolic state). In these situations, it is best to clearly identify the goals of care as being maintenance of patient comfort and prevention of wound deterioration.
If the goal is wound healing and/or the wound is infected, debridement of necrotic tissue is the first step in topical care. We lack definitive data on the best methods of debridement, or the usual time frames for enzymatic and autolytic debridement. Wet-to-dry dressings are still the "default dressing" in many institutions; however, this approach is generally considered suboptimal due to the nonselective nature of the debridement and the pain caused by dressing removal. In considering autolytic debridement, it is helpful to consider the patient’s white blood cell count; white blood cells play a significant role in autolytic debridement, and most clinicians report poor response to autolysis in leukopenic patients.
Preventing Wound Infection
Prevention and management of wound infection is a major concern when dealing with a cancer patient. As the author states, cultures are not routinely indicated; however, most clinicians recommend cultures when clinical infection is suspected, in order to ensure accurate identification of the organism and treatment. Culture technique remains controversial. The Centers for Disease Control (CDC) recommends aspiration, and the Agency for Health Care Policy and Research (AHCPR) guidelines recommend tissue biopsyboth of these approaches involve invasive and potentially painful procedures. In situations where swab cultures are preferred due to simplicity and cost issues, studies indicate that the following technique provides optimal results: Flush the wound with sterile saline, and swab a 1-cm2 area of viable tissue with enough force to produce exudate.
Infection involving the surrounding tissue requires systemic antibiotic therapy. Infections limited to the surface of the wound may be treated with topical agents. Recent studies have shown silver-impregnated dressings and cadexomer iodine(Drug information on iodine) products to be effective in reducing bacterial counts and infectious complications. These products may prevent infections from recurring in susceptible patients.[3,4]
Although it is true that the AHCPR guidelines and some studies suggest that antiseptics such as sodium hypochlorite (Dakin’s solution) and povidone iodine(Drug information on povidone iodine) solution should never be used on open wounds, this remains controversial, because other studies (and many clinicians) support the use of these products for wounds with large amounts of necrotic tissue and/or clinical infection.[5,6] All clinicians agree that these agents should be discontinued when the wound bed is clean.
Dr. Walker states that the key principles of topical therapy are to maintain a moist wound bed and to prevent maceration of the surrounding skin. I would add to this list the importance of lightly filling dead space, effectively managing wound exudate, and protecting the wound from trauma and secondary infection. Dressing selection is based on wound depth (or the presence of dead space) and the volume of exudate. Exudative wounds with depth or dead space require an absorptive filler (eg, alginate rope) in addition to a cover dressing, whereas deep "dry" wounds require a hydrating filler such as a hydrogel (in addition to a cover dressing). Very shallow wounds require only a cover dressing. The specific dressing is selected based on the volume of exudate and the dressing’s absorptive capacity.
Finally, as Dr. Walker notes, there are a number of adjunctive therapies now available. These therapies are designed to have an impact on the wound healing process and are more costly than standard wound care products. They are, therefore, most appropriately used when the goal is wound healing and the wound fails to respond to standard therapy. They would be inappropriate for a "maintenance" situation.
In summary, Dr. Walker has done an excellent job of addressing the pressure ulcer problem in the cancer patient population.