Clinical Activity-Based Cost Effectiveness of Traditional Versus Modern Wound Management in Patients with Pressure Ulcers

Disclosure: This study was supported by ConvaTec, a division of ER Squibb & Sons, LLC, Princeton, New Jersey. This article is translated with permission from the original article, which was published in Japanese in Nippon Ronen Igakkai Zasshi [Japanese Journal of Geriatrics] 2004;41(1):82–91. Introduction In recent years, an alarming increase in the incidence of pressure ulcers has occurred in Japan. The compounding costs of treating these ulcers to a healthcare system are well documented and have served as an impetus for governments and payers to seek ways to reduce the incidence of pressure ulcers and the costs of managing them. As a first step in Japan, the Ministry of Health, Labor, and Welfare has initiated a penalty system to encourage hospitals to implement appropriate risk assessment and risk reduction protocols and tools to reduce the incidence of pressure ulcers. If a hospital does not establish these protocols, and tools and/or the clinical results with respect to pressure ulcer prevention and wound management are below the expected outcomes, financial penalties are instituted. The government has also sought ways to reduce the costs of pressure ulcer management, primarily by focusing on managing the costs of materials, such as pharmaceutical agents and medical supplies. However, significant costs to healthcare systems for treating pressure ulcers lie outside the costs of materials, particularly with respect to the cost of labor and the time a patient spends in the hospital. Thus, it is important to analyze the total cost of particular wound management regimens associated with pressure ulcers rather than only the costs of materials. A recent clinical study confirmed the efficacy of the combination of modern wound dressings and a care algorithm in an American clinical setting.[1] Also, nursing costs were demonstrated to be significantly lower when modern dressings were used,[2] while the average wound management cost per patient was shown to decrease significantly with the use of modern wound dressings, from US $691 without these materials to US $122 with modern dressings. Furthermore, studies in Japan have shown that the treatment cost per pressure ulcer reaches 300,000–500,000 yen (approx. US$ 2,500–4,200) and that cost effectiveness in terms of total care cost per day is likely to be better with modern wound dressings than with gauze and saline.[3,4] Against these backgrounds, a study was conducted to determine the most cost-effective pressure ulcer care procedures in terms of the total cost of care. This prospective, comparative study evaluated the actual cost of care with different materials, with and without standardized wound management algorithms. The activity-based costing (ABC) method[5] was used to calculate the cost of care: this method not only tracks apparent costs (i.e., material costs) but also those costs that concern nursing time, thus providing a more accurate overall cost evaluation. Methods The hypothesis tested was that care involving modern dressings that maintain a moist environment, combined with a standardized wound management algorithm (MC/A group), offers better cost effectiveness than care involving traditional dressings (ointment and gauze), with or without a wound management algorithm, (TC/A and TC/Na groups) in patients with Stages II and III pressure ulcers. The Braden scale[6] was used for risk assessment. This scale analyzes risk factors, such as sensory perception, the level of skin moisture, activity and mobility, and the level of skin exposure to friction and shear. The nutritional status, although part of the standard Braden risk assessment, was excluded in the protocol used for this study. To get an accurate rating of the pressure ulcers and their level or severity, the Pressure Sore Status Tool (PSST) scoring system was used.[7–9] In this system, 13 characteristics of pressure ulcers are scored on a five-grade scale. The characteristics include size, depth, edges, undermining, type of necrosis, amount of necrosis, type of exudate, amount of exudate, color of skin surrounding the ulcer, edema of peripheral tissue, induration of peripheral tissue, granulation tissue (percent), and reepithelization (percent). The maximum score within the system is 65, and the minimum is 13 (no ulcer). The National Pressure Ulcer Advisory Panel (NPUAP) staging system was used for the assessment of pressure ulcer depth.[10] Patients in the study were successively assigned to one the following three groups for comparisons of cost effectiveness: 1. Wound management with modern dressings that maintain a moist environment in combination with a standardized wound management algorithm (MC/A group) 2. Wound management with traditional dressings (ointment and gauze) in combination with a standardized wound management algorithm (TC/A) 3. Wound management with traditional dressings (ointment and gauze) without the use of a standardized wound management algorithm (TC/Na). The maximum participation for all groups was 12 weeks. Prevention measures were the same in all three wound management groups and always included special mattresses. Modern dressings used in the MC/A group included DuoDERM®, DuoDERM® CGF®, DuoDERM® Extra Thin, DuoDERM® Hydroactive® Gel (GRANUGEL), and AQUACEL® dressings (all products of ConvaTec, a division of E. R. Squibb & Sons, L. L. C., Princeton, New Jersey). Traditional materials used in the TC/A and TC/Na groups included tretinoin tocoferil (Olcenon ointment, Lederle, Japan, Ltd.) or alprostadil ointment (Prostandin, Ono Pharmaceutical) for those in the granulation stage, and bucladesine sodium (Actosin ointment, Saitama Daiichi Pharmaceutical) or alprostadil ointments for ulcers in the epithelization stage; A mixture of Bromelain Ointment (J-Dolph) and silver sulfadiazine 1% cream (Geben Cream, Tokyo Tanabe Co., Ltd.) or a mixture of Bromelain Ointment and tretinoin tocoferil (Olcenon) were used as debridement agents.[11] The dressings and ointments to be used for each ulcer stage were grouped for use in the different stages of wound healing. For the TC/Na group where no algorithm was used, in principle, any of the gauze and ointments could be selected during any stage of the wound management process. In addition to the specific materials mentioned in both modern and traditional protocols, supplementary materials and pharmaceutical agents were included in the analysis of costs of materials. These included film dressings, physiological saline, gauze, medical adhesive tape, disposable diapers and diaper pads to absorb excrements, gloves, ointment spatulas, cotton swabs, etc. Cost price sheets were prepared to facilitate calculation of unit prices of medical supplies.[12] If supply purchase prices were unknown or were very difficult to calculate, representative market prices were used for calculations. General pressure ulcer prevention care was included in the protocols as well. For example, a four-inch thick pressure reduction tool (alternating pressure mattress, TriCell® mattress, Kinetic Concepts, Inc., San Antonio, Texas) was used for every patient in this study. Since time spent on management of a pressure ulcer is such an important contributor to the overall cost of care, the cost of labor and the amount of time spent were important items. For the labor cost per minute, data from the Basic Survey on Wage Structure (by Profession) of June 2001 were used. The following formula was used to calculate the labor costs per minute: In the formula, the monthly wage was added to 1/12 of the annually granted compensations (i.e., bonuses) and then divided by the number of work days per month (20), the number of working hours per day (8), and the number of minutes per hour (60). Physicians were mainly involved in pressure ulcer management, while nurses, assistant nurses, and care-workers were in charge of preparation and clean-up before and after wound management, as well as of other nursing activities directly related to pressure ulcer care (e.g., position change, bathing and foot-bathing assistance). Operating (labor) time related to routine pressure ulcer care was recorded based on self-reporting by staff of different professions and rounded up to the minute for each profession. Total time spent (and calculated) included the time necessary for preparation of the dressing materials, time to get from the nurses’ station to the patient’s room, actual time attending to the wound, time necessary to change a patient’s position in bed (sometimes requiring assistance from other nurses or caregivers), time to remove clothing and/or diapers, to give a bed bath, and to wipe and clean skin around the sacrum, time to remove soap residue from a patient’s skin, to provide saline cleansing, and to apply a new dressing, and time to change a patient’s clothes, linen, and position in bed and to clean up after providing care. The amount of wound management materials and time spent were recorded daily on an activity record form using the ABC-based calculation method and specified cost for labor time and materials. The total cost of care was defined as all costs of labor and material. Cost effectiveness to improve pressure ulcer status (V) was calculated as the PSST total score reduction achieved for each yen spent on pressure ulcer care by subtracting the PSST score at the end of study participation from that upon enrollment and dividing this score by the total cost of care. The formula for this type of calculation is as follows: To ensure in-study consistency, study staff underwent extensive pre-trial training with respect to using the PSST scoring tool and the Braden scale, as well as for time keeping. To guarantee impartiality and consistency, data were collected, confirmed, and maintained under quality control conditions by CareBrains, a Japanese Health Economics and Education company. After analysis of all data sets, final outcomes were validated by the investigators. Statistical methods. To verify that the patient populations in the MC/A, TC/A, and TC/Na groups matched on enrollment, Braden pressure ulcer risk and PSST analysis of variance compared these variables for the three groups. Since this was a prospective study designed to test the hypothesis that the protocols of care affected PSST outcomes, statistical analyses of variance were conducted on an intent-to-treat basis to determine significance of the differences among the mean PSST improvement values experienced during a maximum of 12 weeks of management with the three protocols of care. An alpha probability of five percent or less was considered significant. Results The three authors/investigators supervised 13 institutions. Originally, 91 patients were enrolled in the study, but eight patients (9%) dropped out. Thus, 83 patients were included in the final analysis, all with Stage II or III pressure ulcers (Table 1). Forty-eight patients (58%) were male and 35 (42%) female. The mean age was 76.8 years (range: 41–96). Twenty-nine patients (35%) were assigned to the MC/A group (modern moisture retaining dressings with a wound management algorithm), 34 (41%) to the TC/A group [traditional care (ointment and gauze) with a wound management algorithm], and 20 (24%) to the TC/Na group [traditional care (ointment and gauze) without a wound management algorithm]. Analysis of variance did not show significant differences with respect to age at enrollment, size of ulcers, or first day PSST score, indicating that the patients in each group were well matched according to age, size of ulcers, and clinical status of the ulcers on enrollment. The groups were not significantly different in risk of developing pressure ulcers with average Braden scale values upon enrollment reported as: MC/A 12.1 (range 9–22), TC/A 11.4 (range 7–21), and TC/Na 14.6 (range 10–21) (Table 2). Average PSST scores on enrollment were 26.9 (range: 15–40), 29.8 (range: 16–43), and 31.5 (range: 29–39) for the MC/A, TC/A, and TC/Na groups, respectively, with no significant difference between groups (Table 3). Clinical effects (expressed as reductions in PSST score) were compared on a per-patient basis (Figure 1). When Stages II and III pressure ulcers were grouped, the MC/A managed patients showed the best scores (11.1 points reduction), followed by the TC/Na and TC/A groups (9.0 and 6.9 points reduction, respectively). Statistical significance existed (p=0.046) between the MC/A and TC/A groups (Table 4). When Stages II and III ulcers were analyzed as separate groups, results with MC/A were better than those obtained with TC/A or TC/Na, although no significance was reached due to the reduced sample size. With regards to the total cost of care during a maximum period of 12 weeks for Stages II and III ulcers, costs were noticeably different among the three groups (Figure 2): the average total cost in the MC/A group was yen 87,715 (US $730.96), compared to yen 131,283 (US $1,094.03) for the TC/A group and ¥200,584 (US $1,671.53) for the TC/Na group. The MC/A protocol of care was shown to cost significantly less than the TC/Na protocol for total cost as well as when materials and total labor costs were analyzed separately. Similar trends existed but were not sufficiently powered for statistical significance when cost of care was analyzed for patients with only Stage II ulcers (Figure 3). Analysis of the cost of care for patients with only Stage III ulcers showed statistical significance for the total cost of care, labor cost, and material costs when the MC/A and the TC/Na groups were compared (p=0.003, 0.005, and 0.005, respectively) (Figure 4). Cost effectiveness of the three protocols of care was expressed as V=PSST units difference per yen spent. Among patients with Stage II ulcers, the MC/A group (V=0.173) was more cost effective than the TC/A group (V=0.12) and the TC/Na group (V=0.090) but not significantly (Figure 5). Among patients with Stage III ulcers, the MC/A group (V=0.081) was significantly more cost effective (p=0.030) than the TC/A group (V=0.032) and the TC/Na group (V=0.025). When cost effectiveness was compared for Stages II and III ulcers taken together (Figure 5), the MC/A group (V=0.127) was more cost effective than the TC/Na (V=0.045) group and significantly more cost effective (p=0.044) than the TC/A (V=0.052) groups. Discussion The results of this study revealed that clinical outcomes were better in the MC/A group compared with the TC/A and TC/Na groups; healing was better as measured by improvement in total PSST score in the MC/A group. The comparison of costs for materials and labor in Stages II and III ulcers indicates that the costs incurred for both components of care were lower in the MC/A group than in the TC/A and TC/Na groups with a clear indication that labor involved the highest cost, not dressing materials. In all patients with Stages II and III pressure ulcers, the MC/A group was more cost effective in improving pressure ulcer status than the TC/A and TC/Na groups and generated lower costs of care (significant for both labor and for materials). This suggests that modern wound care materials in combination with the use of an appropriate algorithm may reduce the economic burden of pressure ulcer care while improving outcomes for patients. Based on these results, an estimate of the economic effects for a typical Japanese 300-bed long-term hospital can be made. For such an estimate, the occupancy rate of the hospital is assumed to be 90 percent (n=270) and the prevalence of ulcers 5.8 percent (Pr=0.058). Of the pressure ulcers, two out of every three ulcers are assumed to be either in Stage II or III (St=0.67), and the average hospital stay is assumed to be 172 days,12 leading to an annual turnover rate of patients of 2.1 (Tr=365/172=2.1). Using these numbers, a typical 300-bed long-term care hospital would have N x Pr x St x Tr = 22 patients with a Stage II or III pressure ulcers per year. Management of the ulcers of these patients would cost yen 1,929,730 (22 x yen 87,715) or yen 4,412,848 (22 x yen 200,584) for MC/A or TC/Na options, respectively. Thus, the total savings in wound management costs by using the MC/A instead of the TC/Na protocol on patients with Stages II and III pressure ulcers could be up to yen 2,483,118 (yen 4,412,848– yen 1,929,730, US $20,692.65) per year in a typical 300-bed facility: this would contribute significantly to cost reductions. The Japanese White Paper on Health and Welfare 1999 reports that in 1993 in Japan, approximately 0.9 million elderly people were bedridden and estimates that this number would reach 2.3 million by 2025. With the estimated prevalence of pressure ulcers in bedridden patients of 5.8 percent,13 it can be inferred that the number of patients suffering from pressure ulcers was approximately 52,000 in 1993, and that this will increase to 133,000 by 2025. Macro-economically, extrapolation of data generated in our study indicates that the possible differences in cost of wound management with MC/A versus TC/Na could have been ¥5.9 billion in 1993 and would be yen 15.1 billion in 2025 (Figure 6). Conclusion Our results suggest that to lower the cost and improve the cost effectiveness of pressure ulcer care, it is not appropriate to focus solely on material costs. Instead, all factors involved in the cost of care and clinical outcomes, especially labor costs, should be taken into consideration. In this context, modern dressings, if utilized appropriately and with a proven and validated algorithm, can contribute to reduction of costs as well as enhancement of clinical outcomes and ultimately to providing significantly more cost-effective care for pressure ulcers. In terms of macromedical economics, the combination of modern materials and proper algorithms has great potential for contributing to reductions and appropriate allocation of the national healthcare expenditure. While this study was undertaken in Japan, and, therefore, individual aspects of costs of care may be different from the same aspects in other countries, the principles of using ABC are applicable to all clinical situations in the world. It is very likely that studies done in other countries using the same principles of calculating the cost of care will show similar differences: reduction in labor costs brought along by the use of modern dressings may very well coincide with reduction in overall costs of care and with better clinical outcomes.