I received this description of decubitus ulcers from D. Garth Sullivan at INDOX Consulting, a medical expert service:
Chronic lower extremity ulcers affect approximately 2.5 million to 4.5 million people in the US. In addition to pressure ulcers, this growing clinical problem is most prominent among the elderly. Nonhealing or slow healing wounds represent a major health burden and drain on resources and contribute to substantial disability, morbidity, and costs. Multiple factors have been identified as contributors to impaired wound healing, such as, ischemia, infection, advanced age, malnutrition, diabetes, and renal disease. Other conditions, such as cardiac and lung disease, decreased cognitive function, endocrine disease, GI disease, hematologic disorders, incontinence, musculoskeletal problems, neurological disease, alcohol/drug abuse, immunosuppressives, chemotherapy, steroids, smoking, as well as inadequate wound care have been implicated.
Malnutrition has been specifically associated with the extent and severity of pressure ulceration. Appropriate nutritional support, pressure relieving surfaces, turning schedules, and debridement of slough or necrotic tissue are recommended to promote the healing process. Healing rates depend on pressure ulcer stage with approximately 59% of Stage III ulcers and 33% of Stage IV ulcers healing at 6 months. Thomas reports that as few as 13% of pressure ulcers heal within 2 weeks in acute care settings.
Failure to heal diabetic ulcers has been attributed to infection, tissue ischemia, ill-fitting shoes, and poor management. Standard treatment of diabetic ulcers consists of pressure offloading, correction of nutritional deficits, moist wound dressings, and sharp debridement to remove callus. Management principles also include treating infections and preparing the wound bed by topical applications. Brem et al add to these the need for optimal glucose control and the use of adjunctive therapies such as cell and/or cytokine therapy. However, the evidence supporting use of vigorous sharp debridement, enzymatic or autolytic debridement, iodine-based or silver-based antiseptics, and hyperbaric oxygen remains limited. Reported healing rates vary across studies. Piaggesi et al reported a 79% healing rate at 25 weeks after conventional treatment. In contrast, the healing rates in large multicenter trials are reported at 24% at 12 weeks and 31% at 20 weeks. This meta- analysis also concluded that wound duration, area, and size did not significantly affect the percentage of wounds healed at 20 weeks.
Discussion
This study examined subjects with 1 of 3 types of chronic ulcers to identify those factors that influenced the rate of healing, both timely healing (within 3 months of start of treatment), and nonhealing (after 5 to 6 months of treatment). The subjects, all more than 50 years old, were receiving wound care in a variety of settings with different constellations of staff members, care delivery processes and organization, and treatment preferences.
No strong relationship was found between most of the comorbid conditions and the healing outcomes. Diabetes, renal disease, cardiac disease, pulmonary disease, endocrine disorders, GI disease, blood disorders, neurological disease, and smoking were not associated with poor wound healing in the present study, while it was found that diagnoses of malnutrition, infection, CVA, and dementia were important. History of stroke and presence of cognitive impairment are likely to be related to poorer functional status and reduced activity levels, making healing more difficult to achieve. Nutritional status has been linked to the development of pressure ulcers, and is considered an important factor in successful healing of chronic wounds. Subjects who received nutritional support can be assumed to have poorer nutritional status and lowered healing capacity, and thus less ability to heal their wounds. Having more than one ulcer and being obese were both associated with healing within 3 months. These factors may have been associated with type of ulcer (venous), which was likely to heal faster than diabetic or pressure ulcers. However, further analyses showed that the percentage of obese patients was similar between diabetic and venous ulcer patients, and the percentage of subjects with more than 1 wound was similar between pressure and venous ulcer patients. Currently, the explanation to support these findings is uncertain.
It is not surprising that specific wound characteristics were associated with healing or nonhealing of chronic wounds. Larger, deeper wounds take longer to heal than shallow, smaller wounds. Although exudate type did not influence healing in the present study, amount of exudate was associated with both healing and nonhealing of wounds. A major focus of chronic wound care in recent years has been the development of dressings that promote a moist environment to assist healing. Wounds with moderate to large amounts of drainage require absorptive dressings while dry wounds require dressings that add or retain moisture. Recommended dressings include films, foams, hydrogels, hydrocolloids, alginates, and hydrofibers. Dressing materials differ in their properties of permeability and wound protection- understanding these differences is key to planning for wound management in individual patients. The many available dressing choices may confuse clinicians who are making these decisions. In addition to these moisture-management dressings, there are topical antiseptic agents being used with gauze, as well as antimicrobial dressings. Although rationale exists for use of these types of dressings, data are limited on their ability to enhance healing. The findings did not support their use, with antimicrobial dressings having a negative impact on healing within 3 months and a positive association with nonhealing after 5-6 months of treatment. Because of the possibility that use of antimicrobial dressings might be related to presence of infection, we conducted further analyses which revealed no association between presence of infection and use of these types of dressings. Greater use of moisture-management dressings in the first 3 months of treatment, and over all 6 months of treatment, reduced the chances of not healing. The use of moisture-management dressings is consistent with evidence-based recommendations. According to NICE35, moisture-management dressings create the optimum wound environment rather than gauze. Interestingly, the use of gauze dressings in the present study did not influence healing at either 3 or 6 months.
Debridement of the amorphous material from the wound bed of chronic ulcers has been used for many years to enhance healing, using surgical, sharp, autolytic, enzymatic or mechanical approaches. Although evidence supports the efficacy of debridement of chronic wounds, none of the specific approaches has gained universal acceptance.[
Debridement in the present study was associated with poorer healing outcomes. It may be partly due to the fact that necrotic debris increases the possibility of bacterial infection and delays wound healing. It may also reflect use of non-recommended approaches, inadequate skill, and inadvertent damage to healthy granulating tissue. Mechanical debridement is contraindicated because it is nondiscriminant, removing both healthy and dead tissue. As might be expected, the repeated use of mechanical debridement over time was found to be associated with the nonhealing of the chronic ulcers. Although widely recommended, it remains unclear whether wound debridement is a beneficial process that results in greater frequency of complete wound healing.
The literature has described the negative impact of wound infections or bacterial burden on wound healing. The authors of the present study were able to document the negative influence of infectious processes on healing as well. However, infection was not well documented in the medical records (very few cultures were performed), so infections were noted through documented signs of infection, identification of purulent drainage, and/or orders for systemic antibiotics. Ulcers that healed within 3 months had significantly fewer data collection points over these 3 months at which infections or potential infections were noted, while nonhealing ulcers had significantly more data collection points at which actual or potential infections were documented. We also found that greater use of systemic antibiotics was associated with nonhealing ulcers. This of course is correlated with the documentation of signs of infection and might also reflect more severe infectious processes. There is a possibility that antibiotics were overused in some cases.
The present study unexpectedly found that the use of a commercial cleansing agent as compared to water, normal saline, toxic agent, or no cleanser, was associated with faster healing. The use of specific cleansing agents varied significantly across sites of care delivery. The 2 sites with the most positive healing outcomes both used commercial cleansing agents, although for a rather small percentage of their subjects (14% and 9%), while neither of the other two sites with poor healing outcomes used any commercial agents. It is therefore difficult to sort out the independent effects of commercial cleansing agents from other site effects, and requires further investigation. The use of cytotoxic cleansing agents, such as Dakin's solution, acetic acid, and hydrogen peroxide, was associated with the nonhealing of wounds. As early as 1994, AHCPR clinical practice guidelines warned against using these cytotoxic cleansers, but their application persists to this day in spite of the evidence-based recommendations against their use.