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Original Research

Palliative Wound Treatment Promotes Healing

January 2015
1044-7946
WOUNDS. 2015;27(1):12-19.

Abstract

Introduction. Wounds are a major problem at the end of life, affecting nearly one-third of hospice patients. The main patient complaints associated with these wounds are pain, infection, and odor, often making wound care difficult due to patient discomfort and the complicated nature of the wounds.   Materials and Methods. A method of wound treatment invented in 2001 for palliative wound care was designed to meet the goals of pain relief, odor control, and infection prevention. This method, which involved application of viscous lidocaine and topical polymyxin/bacitracin to gauze, was used on hundreds of hospice patients and, later, on non-hospice patients as well. A retrospective review of results was undertaken. Results. This paper presents 2 descriptive retrospective observational reviews. One is a retrospective review of 323 wounds in hospice patients treated over a period of 30 months using the palliative wound treatment method. In this cohort, more than 40% of pressure ulcers healed to closure or were healing by the end of the study; 30% of ischemic ulcers were healed to closure or were healing by the end of the study,; and more than 40% of neuropathic ulcers were healing by the end of the study. In total, nearly 40% of all wounds were in the process of healing or healed to closure. The second study is a retrospective review of nursing home data using the palliative wound treatment method. In a cohort of 72 patients with 156 mixed wound types followed for 1 year, rates of healing to closure approached 95% after 12 weeks of treatment. Conclusion. While meeting palliative goals of reducing pain, preventing infection, and controlling odor, use of this method also provided unexpected healing. Further investigation on use of this method is warranted.

Introduction

  Published data report 35% of hospice patients have wounds. Of those wounds, 50% are pressure ulcers and 20% are ischemic.1,2 The remaining 30% are a mix of various wound types, including surgical, stasis, skin tears, and tumors.1,2 With nearly 2 million patients currently in hospice care,3 this correlates to approximately 700,000 wounds needing care.

  Most chronic wounds are pressure ulcers, a tragic problem for millions of Americans. Five million to seven million Americans develop a chronic wound each year, with the incidence increasing by 10% per year,4 of which 2.5 million of these chronic wounds are pressure ulcers, remarkably close to the 50% noted in hospice.1,5 Pressure ulcers are a significant problem for people who are frail and elderly,6 but also for people who are paralyzed from spinal cord or brain injury,7 or from neurodegenerative diseases such as multiple sclerosis or Huntington’s Disease.8 Pressure ulcers typically occur over a bony prominence that has unrelieved pressure from normal gravitational body force,9 such as the sacrum and heels from lying in bed and ischial tuberosities from sitting. In the United States alone, the pressure ulcer burden is staggering, costing in excess of $9.1 billion for treatment annually.5 These pressure ulcers are full-thickness, often very deep, painful, and prone to infection. Most commonly, these wounds are located on the sacrum or in the pelvic region.1 These wound locations can make treatment very difficult. Contamination with urine and feces is a frequent problem, and fastening a dressing to the wound may be quite difficult due to size requirements, body shape, moisture, fragile/thin skin that tears easily, or the presence of body hair.

  A dressing to effectively treat wounds in the sacral and pelvic region is highly sought after by wound care providers.10,11 There are currently thousands11,12 of pressure ulcer products on the market, yet, while wounds and wound care are fraught with pain, few dressings provide much-needed pain relief. Patients have described pain as the worst part of living with a chronic wound.12 Pain is a complex biopsychosocial phenomenon that requires multiple pharmacological and nonpharmacological management approaches.12

  All open wounds are contaminated with bacteria, sometimes leading to wound infection which is a scourge to patients and caregivers, with some estimates as high as 30% of wounds affected.13 A wound dressing with antimicrobial activity against common wound pathogens would be advantageous.

  For hospice patients at the end of life, goals of care are pain relief, infection prevention, comfort, and dignity. Healing of wounds or wound closure are not considered primary goals for terminal patients, whose average life expectancy is approximately 67 days.3 In 2001, a hospice physician developed a method to meet the palliative objectives of pain reduction, odor control, and infection prevention for wounds in hospice patients.1 Since 2001 this method has been in use on hundreds, if not thousands, of patients in hospice and later for patients not in hospice by the physician who did the original study and invented the treatment.

  Development of wound treatment. The method was developed in 2001 at the bedside, primarily to provide pain relief in dying patients with painful pressure ulcers. At that time there were no guidelines for palliative wound care, and wound healing was seen as an unrealistic goal of treatment in this patient population.14 This technique was not developed from clinical trials or laboratory review, but from a clinical and pharmacological knowledge base of using lidocaine to achieve the level of pain relief desired for palliative wound care. The method involved application of viscous lidocaine and a topical antibiotic to gauze.

  Prior to use, an extensive literature search was conducted to investigate the use of lidocaine in wounds. Animal studies showed mixed results for adequate healing in wounds treated with lidocaine.15-19 Human studies using lidocaine for burns showed it was safe for topical use on a wound, as long as it is below toxicity level.20,21 Nothing in the literature was found to either support or contradict use of lidocaine in the wound bed for pain relief, yet it is known that topical lidocaine can decrease pain.22 Great care was taken to ensure the amounts of lidocaine used were below toxicity level. Brofeldt et al20 studied application of 5% lidocaine to burns up to 28% of total body surface area (BSA). Serum levels never reached toxicity level in his study.20 The palliative wound treatment has less than 2% lidocaine in application, so is safe for very large wound areas, greater than 28% BSA. A viscous lidocaine (containing 2% lidocaine) was selected because of its known safety in common use with humans, low percentage of lidocaine, and because it contains carboxymethylcellulose, which makes a hydrogel that adheres well in an open wound. Hydrogels have an observed benefit in treating various types of wounds, believed to be due to the promotion of the body’s intrinsic autolysis process.23,24 When viscous lidocaine was used, the mixture contained 1% lidocaine, an amount that has shown safe reduction of pain when applied on a wound.22

  Because of the theoretical risk of increased infection due to an altered inflammatory response,25 antibiotics were added with the lidocaine. A simple mixture of polymyxin and bacitracin was created by hand, squeezing approximately 3-4 g viscous lidocaine on gauze, then sprinkling approximately 0.1 g of antibiotic powder over the lidocaine. The mixture was based on reports suggesting this may improve wound healing.26 In vitro efficacy testing later performed on this mixture showed inhibition of 4 of the major wound pathogens: Escherichia coli, Staphylococcus aureus, Candida albicans, and Pseudomonas aeruginosa.27 The addition of antibiotics provided good inhibitory effects against major wound pathogens, but the lidocaine can also contribute to antibacterial effects and bacterial minimization.28,29

  Malodor is a known problem with wounds but the general consensus at the time of this invention was that good cleansing and effective treatment of infection helped reduce malodor. Using an agent such as topical metronidazole for odor was first reported30 in 1993 but was not yet standard of care at the time of development of this method. For the population in this treatment cohort, relieving the patient of the burden of foul odor was paramount. With that rationale, oil of wintergreen was added, using several drops for each wound treated. Oil of wintergreen has a strong and cooling aroma, and it contains 85%-99% methyl salicylate which is aspirin-like and can contribute to pain relief as promoted in commercial literature.31 The National Center for Biotechnology Information features scientific information on the main ingredient in oil of wintergreen, methyl salicylate.32 Since 2001, more research has been conducted on options for controlling odor with different agents.33,34

  An important characteristic is that since the procedure was useful for any type of wound, it was not necessary to characterize the wound. Depending on the type and location of the wound dressed and the top dressing used, the dressing required changing every 1-7 days.

Materials and Methods

  This is a retrospective observational chart review of 2 different cohorts. Study A included 192 hospice patients with 323 wounds treated over 30 months; Study B included treatment of 156 pressure ulcers and other wounds in 72 nursing home patients over 12 months. Study A is from previously published data and results;1 the current report details specific treatment not covered in the previous report.

  Study A. Study A consisted of 192 hospice patients with 323 wounds treated over a 30-month period. Types of wounds included pressure, neuropathic, ischemic, and other. Wound treatment selection was determined by hospice physician recommendation and patient/caregiver consent. Consent was obtained as part of standard practice for any treatment offered. With patient or caregiver permission, wounds were treated with the mixture of lidocaine and topical antibiotic, moistened as needed with normal saline, and applied on a gauze to fit the wound. Wound dressings were either changed daily, less frequently if the wound was dry, or more frequently if there was heavy drainage. Not all patients or caregivers gave permission for use of this treatment; some were afraid of using lidocaine in the wound, some did not perceive it as aggressive treatment, and some thought it seemed too unusual to work. Therefore there were 92 (28%) wounds treated with another modality based on their physician’s orders, including various types of dressings such as wet-to-dry, hydrocolloids, alginates, or vacuum-assisted closure (VAC).1 The new method, which will be referred to as the novel dressing, was used to treat 231 (72%) wounds. Ninety-two wounds were treated with other methods. Wound healing was determined by the traditional method of measuring length and width, evaluating the amount of drainage, and assessing the wound tissue for granulation, slough, or necrosis. A wound was considered to be healing if it showed contracture with granulation and decreased size. Wounds were assessed weekly by a nurse, and every 1-3 weeks by the hospice physician. Since the palliative goals of care were to relieve pain, control odor, and prevent infection, these parameters were evaluated with each assessment. Since the majority of patients were nonverbal no analog scales were used; evaluations depended on nursing assessments. Pain assessment was made by observing patient facial expression, body movement, and noting if the patient moaned or cried during treatment.

  This method provided a primary wound dressing, but a secondary dressing was usually needed. In keeping with the desire for simplicity and maintaining comfort, the top dressing was provided by applying a thick layer of zinc oxide ointment around the wound with a sheet of plastic wrap placed on top and pressed into the zinc oxide ointment.

  Study B. As stated, use of this treatment method expanded from hospice to non-hospice in the wound center of a long term care facility (Clovernook Health Care Pavilion, Cincinnati, OH) which used it exclusively. Over a 1-year period in this nursing home, 156 wounds—including venous, diabetic, surgical, ischemic, and stage 2-4 pressure ulcers—in 72 patients were treated with the lidocaine and antibiotic mixture on gauze, which was changed daily. Some of these patients actually were in hospice, but not identified in Study B. Wound healing was judged by the traditional method of measuring length and width, evaluating the amount of drainage, and assessing the wound tissue for granulation, slough, or necrosis. A wound was considered to be healing if it showed contracture with granulation and decreased size. Pain and odor were also observed, but not reported in Study B. Wounds were assessed weekly by the wound nurse, who held wound care certification (WCC) from the National Alliance of Wound Care and Ostomy, and every 1-2 weeks by the director of wound care for the nursing home. Wounds were followed to closure. In this nursing home, all patients with wounds also had static air pressure support with mattress overlays and chair cushions (EHOB, Inc, Indianapolis, IN). This data was from nursing home wound records, and was not published.

Results

  Study A. For Study A, the median age of patients treated was 82. Most patients lived less than 30 days, with a median of 31 days. Healing to closure was not an endpoint in treatment of this cohort as most of the patients would not live long enough for their wound to achieve closure. According to nursing reports, odor and pain were reduced. Pain relief was immediate in most cases, and persisted with use of the novel dressing. In the cases treated, no infections occurred with use of the dressing. Odor was also well controlled. Besides reducing pain, preventing infection, and controlling odor, healing results were surprising. More than 40% of pressure ulcers healed to closure or were healing; 30% of ischemic ulcers were healed to closure or were healing; and more than 40% of neuropathic ulcers were healing (Figure 1). There were no allergic reactions reported. Allergic reaction to lidocaine has been found to be low, < 0.7%.22 The top dressing used was very successful in that it kept the wound dressing moist and warm, which are both adjuvants to healing,35 and prevented trauma to periwound skin with dressing changes.

  Included in Study A were 24 diabetic foot wounds treated over the 30-month period. Eleven (46%) healed to closure or were healing, no new wound infections presented, and there were no amputations.

  A comparison of 231 wounds treated with the novel dressing vs the 92 wounds receiving other treatments is shown in Figure 2. Overall, 40% of wounds treated with the novel dressing healed to closure or were healing vs 10% of wounds treated with other modalities.

  Since the novel dressing uses gauze it is interesting to look at a published study of VAC vs moist gauze healing (Figure 3).36 Wound volume reduction was assessed at 3 and 6 weeks in 18 patients with chronic nonhealing sacral/pelvic ulcers in each arm of the study. While no direct comparison can be made, the results from 12 hospice patients in Study A with sacral/pelvic ulcers that were examined at 3 and 6 weeks were compared to the published study.36 Because of the difference in sample sizes, no direct comparison can be made, but results are intriguing, nevertheless, especially since the VAC and gauze arms excluded patients with malnutrition, renal failure, infection, cancer, or other chronic disease requiring treatment, and the novel dressing arm had no exclusions. Patients in the novel dressing arm were also much older, on average 87 years old vs an average of 56 years old in the VAC arm and average 49 years old in the gauze arm.

  Study B. The unpublished results of the use of the novel dressing in nursing home patients is shown in Figure 4. Overall, almost 95% of wounds were closed by 12 weeks. These results can be compared to a study published by the University of Pennsylvania that reported healing rates over 24 weeks of venous and diabetic ulcers.37

  This University of Pennsylvania study was published to demonstrate the expected healing rate using wound treatments that those “skilled in the art”—clinicians who regularly practice wound care, according to the study—would use. The venous ulcer cohort had compression wraps, and the diabetic foot cohort (actually the combined results of 5 different studies) used saline-moistened gauze. These healing rates represent what healing could be achieved with good wound care (ie, standard care), suggesting that any new therapy should be compared against this yardstick. This was used as a comparison for healing rates using the novel dressing. The expected healing rates did not include hospice patients, and patients with peripheral (arterial) vascular disease were excluded in the diabetic foot cohort.37 Patients in the novel wound dressing arm often had peripheral vascular disease, and a portion were hospice patients, thus making this group less likely to have wounds that healed. The wounds in the novel dressing arm included venous ulcers and diabetic foot ulcers, but also included pressure ulcers, surgical wounds, and arterial wounds. This makes comparison difficult, plus there are fewer data points in the novel dressing arm. The novel dressing arm only followed patients for 12 weeks since healing rates approached 95% by that time, compared to 24 weeks in the University of Pennsylvania study. While a statistical evaluation is not possible, the results are interesting. At 4 weeks, the novel dressing cohort had achieved healing rates equal to the best expected at 24 weeks in the University of Pennsylvania study.

Discussion

  The wound treatment under discussion is a novel dressing using common, ordinary materials in an uncommon way. The ingredients used to make this dressing were gauze, viscous lidocaine, polymyxin/bacitracin antibiotic, and oil of wintergreen. Gauze was the substrate, often discounted, but yet very versatile and useful. Gauze can be shaped to any size or form, can be used to moisten or dry a wound, and can easily be combined with other products. Viscous lidocaine not only provided lidocaine for pain relief, but the viscous part is a hydrogel which brings advantages such as maintaining moisture and promoting autolytic debridement. It also controls the pH, making a slightly acidic wound dressing.38 The chosen antibiotic has broad antibacterial activity and Kaye26 noted it hastened wound healing. Also, in vitro studies with the novel dressing show inhibition of some common wound pathogens, including E. coli, S. aureus, P. aeruginosa, and C. albicans.27 The oil of wintergreen is a natural oil added to the antibiotic ointment in small amounts for odor control. Both of the reviews, Study A and Study B, reported that when using the novel dressing there were no new infections, odor was controlled, and pain was relieved or reduced.

  While the original goals of treating pain and preventing infection were met, a surprising outcome was the improved healing of wounds. Initially, there was no goal of healing in terminally ill patients; however, wounds improved and even healed in this very fragile group of patients. All the wounds had prior treatment, some with surgery, and most with multiple types of dressings, such as wet-to-dry gauze, hydrocolloids, alginates, silver dressings, or VAC. In all cases, this was the first treatment that had worked to help heal the wound. And in all cases, healing was not expected due to that patients conditions, some with terminal wounds.39 The results seen with this treatment method were surprising to observers, with more than 40% of the wounds healed or healing at the end of the study period. Because of the success with the hospice patients, this method was used with non-hospice patients as well. The current study reports the results of healing in the hundreds of wounds treated with this method compared to reported results in Study A and Study B.

Limitations

  These studies are all observational, not experimental. Study A is actually quasi-experimental because the assignment of treatment was not random, but elected by the patient or caregiver. All individuals were simply observed, whether or not they had the intervention, and outcomes subsequently assessed. Data collected for both cohorts was the primary data collected by the investigator.40

  Even though this was observational research, issues of bias, precision, validity, confounding, and chance must still be considered. In cohort design such as in these studies, selection bias by the investigator must be considered, but in this case the investigator did not select participants, they selected themselves by consenting or not consenting to the treatment with the novel dressing or, in the case of cohort B, participation was mandatory per the nursing home. All patients in this cohort had given consent to treatment by the wound center on admission to the nursing home.

  Confounding factors can be controlled in an observational study by restricting such factors, or by adjusting the analysis. In these cases, possible confounding conditions were noted (ie, comorbidities) but are not really confounders because they are intermediate steps in wound development.

  Statistical analysis was not done to rule out chance as a cause of results, but common sense and clinical experience would judge the results as meaningful, though not statistically significant.

  These studies have strong internal validity and precision with lack of random error or systematic error. External validity also applies because the sample size is large and representative; however, the external validity will be confirmed when similar results are replicated in different populations, places, and time periods.41 The primary endpoint of Study A was management of wound symptoms in hospice patients. In Study B, the primary endpoint was wound healing. In both respects, the novel dressing was adequate

Conclusion

  In summary, a wound treatment combination developed to care for pressure ulcers and other severe wounds, using an unexpected mixture of common ingredients, resulted not only in achieving the intended goals of relieving pain, controlling odor, and preventing infection, but also had the unanticipated consequence of improved wound healing. Additionally, while the treatment was developed primarily for pressure ulcers, it also proved effective for other deep wounds, such as arterial, neuropathic, and venous ulcers.

  This ability to impact a variety of wounds is an advantage of the novel dressing that dramatically simplifies wound care. Most other dressings are developed for a particular type of wound, and the provider is required to assess and diagnose the wound in order to select the appropriate dressing. This novel dressing eliminates that need, thus making effective care much easier to provide. The results seen with this treatment method suggest that further evaluation is warranted.

Acknowledgments

  The author is from AT Squared, LLC, Blue Ash, OH.

Address correspondence to:
Aletha W. Tippett, MD
AT Squared
10274 Alliance Road
Blue Ash, OH 45242
tippettaw@fuse.net

  Disclosure: The author discloses she is owner and president of AT Squared, but this presents no financial or other conflict of interest in relation to this manuscript.

  This material was previously presented in a lecture, “Novel Palliative Wound Dressing Promotes Healing,” at the Symposium on Advanced Wound Care & Wound Healing Society 2007; April 28-May 1, 2007; Tampa, FL.

References

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