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A Three-Year Multiphase Pressure Ulcer Prevalence/Incidence Study in a Regional Referral Hospital

Empirical Studies

A Three-Year Multiphase Pressure Ulcer Prevalence/Incidence Study in a Regional Referral Hospital

Index: Ostomy Wound Manage. 2004;50(11):32-40.

    A pressure ulcer is any lesion caused by pressure resulting in damage of underlying tissue.1 At least 3 million adults in the US are reported to have pressure ulcers yearly.2 Pressure ulcers can have a devastating impact on health and care provision, ranging from patient discomfort to increased healthcare costs. Conservative cost estimates of caring for a patient with a pressure ulcer range from $500 to $50,000.3 The average hospital incurs $400,000 to $700,000 annually in direct costs to treat pressure ulcers.4

    Nosocomial pressure ulcers in hospitals are one indicator for quality of care. The key to successful outcomes is early assessment and interventions to prevent or reduce their incidence.5 Baseline and ongoing prevalence and incidence studies can help achieve the desired outcomes and measure the effectiveness of interventions implemented in pursuit of those outcomes.
Prevalence is defined as the proportion of a group that has a pressure ulcer at a given time, which may be a single point in time or a time period during which the cases are counted. Incidence is the proportion of the group initially free of pressure ulcers that develop them during a specified period of study.6

    The cornerstone of pressure ulcer prevention is identifying and minimizing risk factors with the use of a validated risk assessment tool such as the Braden Scale. The AHRQ Pressure Ulcer Prediction and Prevention Guidelines list several other recommendations related to maintaining tissue tolerance to pressure. Among these recommendations are the use of mild cleansing agents to minimize dryness and treating dry skin with moisturizers.5 Healthcare agencies that implement focused skin care protocols to prevent pressure ulcers and intervene as early as possible have been able to demonstrate reductions in the prevalence and incidence of pressure ulcers.7,8

Skin Physiology and Related Care

    Determining who is at risk for pressure ulcer development requires some understanding of the physiology of the skin. The largest organ, the skin is the dividing line between an individual and the environment. The skin protects against infectious micro-organisms, ultraviolet light, noxious substances, and excess fluid electrolyte loss and is instrumental in thermoregulation, sensation, metabolism, and communication.9 The skin’s protective function is a complex process involving the acid mantle (pH 4.5 to 6), normal skin flora, and lipid barrier (sebum and extracellular lipids located in the cell layers of the stratum corneum). The stratum corneum (horny layer) is continuously exposed to the outside environment, providing the first line of protection, and is a vital part of the body’s immune system.10 The acidic environment and normal flora (resident micro-organisms) reduce the chance for pathogens to invade, contributing to the body’s immune response.

    The pH and surfactant system of a skin cleanser may influence the skin’s pH and lipid barrier. Washing with an alkaline soap can increase the pH of the skin and reduce the lipid barrier; therefore, a product with a pH of 4 to 7 and gentle surfactant system is recommended for skin cleansing. This is particularly important for the elderly patient population, whose skin is dryer, more prone to cracking, and slower to recover from the effects of alkaline substances.11 In addition, the act of cleansing involves friction, which further insults the stratum corneum. Dry stratum corneum and friction are generally accepted as precursors to pressure ulcer development and can be partially offset by using moisturizers to facilitate stratum corneum hydration.5,12-14

    Up to 33% of hospitalized patients have perineal dermatitis,15-17 an inflammation of the skin that usually occurs from a combination of moisture, chemical, and/or mechanical irritation. When left untreated, the denuded skin can progress rapidly to ulceration and secondary infection.18 Up to 66% of hospitalized patients have fecal incontinence19; Maklebust and Sieggreen12 found that patients with fecal incontinence are 22 times more likely to develop a pressure ulcer in the perineal area.

    Prevention and treatment of perineal dermatitis are based on procedures to cleanse, moisturize, and protect the skin from the detrimental effects of moisture and enzymes from feces and stool.20 Irritants such as effluent and bacteria should be removed from the perineal region with a perineal cleanser, pH balanced to the acid mantel of the skin, as soon and as gently as possible. Cleansing should be followed by the application of a perineal skin barrier.2,5,21


    To measure the outcomes of skin integrity interventions on the incidence of pressure ulcers in a referral hospital, a multiphase project was initiated in a 154-bed regional tertiary care hospital located in an urban community in Ontario, Canada, that provides care to an urban and rural population. The objectives of the multiphase prevalence and incidence study were to determine: 1) incidence of pressure ulcers before and after implementation of an all-body cleanser, lotion, no-rinse perineal cleanser, and perineal skin protectant cream; and 2) the incidence of pressure ulcers before and after implementation of pressure ulcer prevention protocols, modified documentation methods, staff education, use of advanced wound care dressings, and improved support surfaces.

    Study population. The study subjects included adult male and female patients who were hospitalized on the day of each study. Eighty-four (84) subjects were included in the first study to establish baseline data; 77 subjects were included in the second study to evaluate a group of interventions (Phase 1) that had been implemented; and 100 subjects were included in the third study to evaluate a group of interventions (Phase 2) that had been implemented. The median Braden scores ranged from 15.5 to 16 (see Table 1). Subjects were located in five units: surgical, medical/palliative, chronic/rehabilitation, telemetry, and intensive care. Patients in the psychiatry and maternal child/obstetrics units were excluded.

    Data collection. Data were collected by the authors and nurses from the Southwestern Ontario Evidence-Based Pressure Ulcer Prevention and Treatment Initiative, which is fully funded by the Ontario Ministry of Health and Long Term Care and the Integrated Strategic Alliances Portfolio of the London Health Sciences Centre and St. Joseph’s Health Care, for the first and second study. For the third study, data were collected by the authors with an additional nurse to verify the data. Data were collected through chart review and a head-to-toe skin inspection of each patient present on the units on the day of the study. Researchers used a form designed for this study by the Southwestern Ontario Evidence-Based Pressure Ulcer Prevention and Treatment Initiative. The data collection form included pressure ulcer location, pressure ulcer stages (Stage I through Stage IV) using the National Pressure Ulcer Advisory Panel (NPUAP) Staging System,13 and documented care plan components. The data collection form was completed after skin inspection once a pressure ulcer was discovered. Pressure ulcers were considered nosocomial if they were not documented within 24 hours of admission of the current hospital stay.

    Risk assessment scores were calibrated for each patient using the Braden Scale for Predicting Pressure Sore Risk. The scale is composed of six subscales: sensory perception, moisture activity, mobility, nutrition, and friction/shear. All subscales except friction/shear are scored on a 1 = high risk to 4 = low risk format, with a lower score indicating higher risk. Friction/shear are scored 1 = high risk to 3 = no risk.22 The Braden Scale was used for the prevalence/incidence study data collection; it was not implemented as a patient care intervention until Phase 2 of the 3-year project. Braden scores were determined for patients who actually had pressure ulcers.

    In accordance with the University of Western Ontario Ethics Review Board protocols, the study did not require written patient consent. The head-to-toe skin assessments do not exceed regular patient care standards. All information collected was kept confidential and in a secure area.

    The authors and members of the Southwestern Ontario Evidence-Based Pressure Ulcer Prevention and Treatment Initiative completed skin inspection and relevant forms for the first (baseline) and second (post Phase 1 interventions) study. Data were analyzed by members of the Southwestern Ontario Evidence-Based Pressure Ulcer Prevention and Treatment Initiative. For the third study (post Phase 2 interventions), the authors were responsible for obtaining data from skin inspection and for completing the forms; an additional nurse verified the data. 

    Members of the Southwestern Ontario Evidence-Based Pressure Ulcer Prevention and Treatment Initiative educated the authors on skin and risk assessments before they began to collect data. Three nurses simultaneously evaluated each patient to verify the results. Data collection took more than 16 hours of 1 day for the base line study and 9 hours over 1 day for each of the two follow-up studies.

    Data analysis. A statistician was hired to analyze the data. Descriptive statistics were calculated and analyses were performed to determine if changes in incidence rates were statistically significant. Phase 1 and Phase 2 results were separately compared to baseline results. The null hypothesis of equal proportions using a one-tailed test was performed.23

    Phase 1 procedures. Following the results of the baseline prevalence and incidence study in 2000, it was determined that prevention interventions should be implemented. Skin care products were selected and implemented through the following process:

  • The authors and committee members reviewed samples of products available on the market
  • Nursing staff used, evaluated, and solicited patient input for several selected products based on effectiveness, user acceptance of packaging, and product feel and fragrance
  • Nursing staff completed comment sheets
  • The authors negotiated with materials management for product selection after the baseline study results were presented. Shared goals included product standardization and cost, clinical effectiveness, and prioritizing nursing staff input
  • The skin care products selected were a gentle pH-balanced liquid cleanser (Gentle Rain® Extra mild, Coloplast Corp., Marietta, Ga.); a longer lasting lotion (Xtracare®, Coloplast Corp., Marietta, Ga.); a no-rinse incontinent skin cleanser (Periwash® II, Coloplast Corp., Marietta, Ga.); and a combination skin protectant cream (Baza® Protect, Coloplast Corp., Marietta, Ga.)
  • Nursing staff were in-serviced on the procedures for product use and posters were placed on the units to reinforce the in-service information.

    Approximately 1 year later, after the phase 1 interventions were in place, a second prevalence and incidence study was conducted.

    Phase 2. Phase 2 interventions included modified and more complete documentation related to prevention, assessment, and treatment of skin breakdown; advanced wound care products; replacement mattresses designed to reduce pressure on heels; and low-air-loss mattresses for use with patients who had the highest pressure ulcer risk as determined by their Braden scores. Phase 2 interventions commenced with a nursing staff education day. Education included instruction on:

  • Prevention, assessment, and treatment of wounds
  • Use of the Braden Scale for Predicting Pressure Sore Risk and corresponding protocols
  • Modifications to a skin assessment form to include tissue consistency, temperature, and skin hydration (dry or moist)
  • Modifications of wound assessment (wound edges, pain, wound bed, periwound skin, and measurements)
  • Improved documentation options for selecting interventions.


    Two hundred, seventy-two adult male and female subjects (n = 84 at baseline, 77 during study Phase 1, and 100 during Phase 2) participated in this study (see Table 1). Eleven subjects declined assessment or could not participate due to extenuating circumstances, including impending death (expected the day of the study), patient or family refusal, and patients who were in the OR. All stages of pressure ulcers were represented in the data with no unusual trends noted. The majority of the pressure ulcers were located on the coccyx and heels (see Table 1). 

    Of the 84 patients assessed at baseline, 15 (17.9%) developed 22 pressure ulcers while hospitalized. Of the 77 patients entered into the Phase 1 part of the study, four developed pressure ulcers (an incidence rate of 5.2%). Of the 100 patients entered into Phase 2, two developed pressure ulcers (an incidence rate of 2.0%). Compared to baseline, the incidence of nosocomial pressure ulcers was significantly lower during Phase 1 (Z score 2.50) and Phase 2 (Z score 3.66) of the study (see Table 2).


    The authors believe the project was successful due to the interventions and staff determination, collaboration, and desire to improve quality of life for patients in a measurable way. Staff nurses were empowered — their experience and input were solicited, valued, and utilized.

    The most surprising result was the significant (17.9% to 5.2%) reduction in the incidence of pressure ulcers observed. A study by Hunter et al24 also found a statistically significant drop in the incidence of pressure ulcers (19.9% to 8.1%) in two nursing homes after implementing a body wash and skin protectant. Studies like these have important implications for practice. The findings emphasize the importance of standardizing care and of using quality skin cleansers, moisturizers, and barriers as important components of a pressure ulcer prevention program. More studies are needed to provide evidence related to the association between xerosis (dry skin) and pressure ulcers in clinical practice guidelines such as the AHRQ and WOCN.5,13
The interdisciplinary culture of the hospital improved because of the project. The nutrition indicator in the Braden Scale prompts more timely dietary consults and the Braden Scale also provides the evidence needed to obtain chair cushions from Occupational Therapy. Other changes noted include a decrease in wet-to-dry dressing use and less nursing time needed to care for pressure ulcers. Additional studies are needed to quantify if the costs of obtaining quality skin care products are offset by a reduction in the cost of wound care supplies used.


    Limitations to the study include the limited demographic data for analysis of case mix group differences. Important acuity information could have been determined through medical diagnosis and Braden scores. Braden scores were only determined for those patients who actually had pressure ulcers. Braden scores on all patients would have given important acuity information to compare subjects from year to year.

    Pressure ulcers were considered nosocomial if they were not documented within 24 hours of admission. During chart audits for the first 2 years of the study, documentation of skin assessments on admission was completed only 75% of the time (see Table 3). By the year 2003, documentation data collected revealed 100% compliance with documenting skin assessments on admission. The improved documentation on admission could have assisted in the decrease of nosocomial wounds simply by improving the identification of pressure ulcers that were already present on admission. The effect of these changes in practice and potential patient population related differences cannot be ascertained based on the data available.


    Addressing the problems of potential discomfort, disfigurement, and extended stays in the hospital due to pressure ulcers is of tremendous benefit. Perhaps the greatest benefit of this project’s outcomes is patient satisfaction. Future research on prevention of nosocomial pressure ulcers is warranted and should include direct measurement of patient satisfaction.


    The authors would like to acknowledge and thank the Southwestern Ontario Evidence-Based Pressure Ulcer Prevention and Treatment Initiative, fully funded by the Ontario Ministry of Health and Long Term Care and the Integrated Strategic Alliances Portfolio of the London Health Sciences Centre and St. Joseph’s Health Care; Stratford Hospital administration and colleagues; Stratford Hospital Hospital Auxiliary and the Hospital Foundation; Equip to Care Foundation for their generous donations to purchase support surfaces; Coloplast Canada for providing an educational grant; Stephen E. Bohnenblust, EdD, Professor, Department of Health, Minnesota State University, Mankato, Minn., for providing the statistical analysis; and Denise Nix, RN, MS, CWOCN, Associate Director webWOC Nursing Education Program, and Cathy Garvin, RN, CWOCN, Senior Manager, Clinical Development, Coloplast Corp., Skin Care Business Unit for providing a literature review.