Knowledge of Pressure Ulcers by Undergraduate Nursing Students in Brazil

Abstract

  The purpose of this study was to examine Brazilian nursing students’ knowledge of pressure ulcers. Third- and fourth-year undergraduate baccalaureate students at a public university in Brazil (N = 83) were asked to provide demographic information, identify extracurricular activities (eg, reading journals and articles and using the Internet to enhance comprehension of pressure ulcer care), and complete the Pressure Ulcer Knowledge Test. Students correctly answered 67.7% of the Pressure Ulcer Knowledge Test items. Students who participated in extracurricular activities and used the Internet had significantly higher Knowledge Test scores than those who did not. Readings did not significantly impact the Knowledge Test score. Generally, the students were found to have low pressure ulcer knowledge, but that educational programs and the Internet have the potential to positively impact nursing students’ knowledge of pressure ulcers.

  Globally, maintaining skin integrity and preventing pressure ulcers have traditionally been the responsibility of nurses. The presence of pressure ulcers in hospitalized patients has been identified as a quality indicator in healthcare.¹ Prevention requires a systematic evaluation of the patient for the risk of developing pressure ulcers and adoption of appropriate preventive measures. Gray² stated that it was the responsibility of educational institutions to ensure that nursing students obtain the necessary knowledge for practice while they are still completing their undergraduate program. Therefore, nursing educational programs need to ensure that students receive the necessary knowledge for pressure ulcer prevention, staging, and description. The purpose of this study was to examine Brazilian nursing students' knowledge of pressure ulcers.

Literature Review

  Internationally, various researchers have investigated the knowledge and clinical practice of nurses and nursing students concerning the prevention and treatment of pressure ulcers. Several studies have been conducted in the United States. Moody and colleagues³ presented an intensive educational program about the pathogenesis, assessment, treatment, and prevention of pressure ulcers to nurses and physicians. This program resulted in a decrease in pressure ulcers, decreased use of specialty beds, and cost savings. Bostrom and Kenneth⁴ surveyed staff nurses about their knowledge of pressure ulcer risk factors, interventions for maintaining skin integrity, and factors that hinder preventive care. They reported a high knowledge of risk factors, but found that nurses lacked interest and gave prevention a low priority in care. Lack of staffing and costs were identified as additional barriers to pressure ulcer preventive care. Hayes, Wolf, and McHugh⁵ examined the impact of a pressure ulcer educational program on nurses' knowledge of risk, assessment, and treatment. Nurses in the pressure ulcer knowledge program versus a control group improved their knowledge. Beitz and colleagues⁶ identified that professional and nonprofessional nursing staff members were poorly informed in several basic aspects of pressure ulcer care. Nursing staff desired more wound care information. Pieper and Mott⁷ noted that the more recently nurses had heard a lecture or read an article, the higher (significantly) their knowledge about pressure ulcers. Knowledge scores were not related to nurses' educational background, age, or years of work experience.

  In Britian, Hill⁸ observed nurses providing patient care and subsequently tested them about pressure ulcer prevention. Nurses were knowledgeable about dressings and nutritional assessment, but failed to implement their knowledge of pressure ulcer risk assessment. Hill⁸ recommended educating nursing students about pressure ulcers and updating nurses' knowledge. Russell⁹ queried nurses from two patient care units about their pressure ulcer knowledge and practice. She identified gaps in knowledge, such as capillary pressures and pressure ulcer staging, and recommended more post-basic education about pressure ulcer prevention and treatment. Maylor and Torrance¹⁰ surveyed nurses about their knowledge and attitude about pressure ulcers. They could not identify a knowledge deficit. The failure to prevent pressure ulcers was suggested as a problem with individual or organizational motivation. In contrast, Gerrish and colleagues'¹¹ survey and audit of the knowledge of risk assessment and its documentation noted deficiencies in both. Mockridge and Anthony¹² noted nurses' knowledge of pressure ulcer treatment and healing was higher for those ranked at the senior versus junior level.

  A study of 34 nurses in Hong Kong examined knowledge and practice of preventing and treating pressure ulcers in the elderly.¹³ Nurses had sound knowledge of prevention and treatment, but inconsistencies occurred in practice. In the Netherlands, researchers studied the extent to which pressure ulcer preventive methods were used and nurses' knowledge and beliefs regarding the usefulness of these methods.¹⁴ The study was based on a consensus committee report. Nurses reported using many preventive methods that the consensus committee had judged as not useful and not using those judged as useful. The authors concluded that a knowledge deficit existed with regard to the information from the consensus committee.¹⁴ A Swedish study examined nurses' knowledge of pressure ulcer risk, prevention, and treatment for patients with hip fractures.¹⁵ Nurses primarily used repositioning, lotion, and pressure reducing surfaces; whereas, nutritional support, reduction of shear and friction, and patient education were only employed to a small extent. The authors concluded that nursing staff knowledge and documentation could be improved.¹⁵

  Few studies could be found about nursing students. Gould¹⁶ surveyed nursing schools about pressure ulcer education. Faculty believed that pressure ulcer content received a low priority. It tended to be presented at the beginning of a student's program and rarely updated or discussed again. Although the textbooks in the study have been revised since the study was published, Vogelpohl and Dougherty¹⁷ noted that nursing textbooks tended to present pressure ulcer content sparsely; at times, it was incomplete and inaccurate. They concluded that students were dependent upon clinical experience, self-study, and the faculty to enhance their background regarding pressure ulcer risk, prevention, and treatment.

  In Brazil, Rabeh and Caliri¹⁸ conducted a study to identify the teaching-learning experiences of 31 students in the last term of the undergraduate nursing program in a private school. In that sample, 97% of students cared for patients with pressure ulcers, having acquired their skills in their Fundamentals of Nursing course. The measure most frequently used for prevention was postural alignment. They also employed practices that are ill-advised, such as the ring cushion, local massage, and soap and povidone iodine for wound cleansing. The authors concluded that students' knowledge about pressure ulcer prevention and treatment was low and care, at times, inappropriate.¹⁸ The above findings were similar to Pearson and colleagues,¹⁹ who reported pressure ulcer prevention and treatment varied, ranging from turning the patient and using occlusive dressings to sunshine exposure and airing the wound. The authors concluded that despite years of attention to pressure ulcer prevention and treatment, pressure ulcers remained a significant problem in Australia.¹⁹

  Rangel and colleagues²⁰ interviewed 33 nursing students at a university in Brazil about their pressure ulcer care. Less than half of the students (48%) had delivered prevention or treatment to patients at risk for pressure ulcers or with pressure ulcers; 33% had never provided this care; and 18% had only observed the care. The students who performed pressure ulcer prevention and treatment care cited an average of 10.2 pressure ulcer care measures for these patients; whereas, those who had never provided the care or only observed procedures cited an average of one measure. Among the measures utilized for treatment, 21% were considered to be inadequate according to standardization in scientific literature. The authors concluded that nursing practice impacted students' knowledge of pressure ulcer prevention and treatment.²⁰

  In summary, findings about nurses' knowledge about pressure ulcers vary. Nurses first learn about pressure ulcers in their educational programs. A few authors conclude that knowledge is appropriate, but implementation of care is weak; others have identified low knowledge or misconceptions about pressure ulcers. A common thread is that continued education is necessary. Knowledge for students can be achieved through theoretical and practical teaching in undergraduate nursing programs; by participating informally in optional courses, lectures, and extracurricular activities, and/or by reading articles and information on the Internet and the like.

  Worldwide, nurses are concerned about knowledge of pressure ulcer prevention and treatment as evidenced by national studies of nurses and development of consensus statements. Since 1998 in Brazil, the guideline, Pressure Ulcers in Adults: Prediction and Prevention²¹ has been available in Portuguese on the website of the University of Sao Paulo at Ribeirao Preto College of Nursing. The document is also disseminated during classes, courses, and lectures. The purpose of this study was to examine Brazilian nursing students' knowledge of pressure ulcer prevention, staging, and wound description. The following research questions were examined:
   1. What is nursing students' knowledge about pressure ulcers?
   2. Is nursing students' knowledge associated with other learning methods such as extracurricular activities, reading, or use of the Internet?

Method

  Subjects and setting. The study was completed with students (N = 83) at the end of their third or fourth years of the undergraduate baccalaureate nursing education at a public university in Sao Paulo State, Brazil. A sample of 83 has the power of .87 to detect a large effect, 2-tail alpha = .05. All students in the third and fourth years (N = 166) were invited to participate. Fifty-three students from the third year (63.9% of the class) and 30 students from the fourth year (36.1% of the class) agreed to participate. The difference in participant numbers between the third-year and fourth-year students was due to difficulties locating the latter because they were in a full-time period of clinical training in different healthcare institutions, often far from where data were collected. Because the students had studied the pressure ulcer curriculum during the second year of their education and did not differ in their total score on the Pressure Ulcer Knowledge Test, students were considered as a total group for statistical analyses.

  The research project was evaluated and approved by the institution's Committee of Regulations and Ethics. The study was explained to the students and signed consent was obtained. Participation or nonparticipation did not affect the students' grades. Data collection occurred during the last week of class in December 2000.

  Instrument. The Pressure Ulcer Prevention Survey was adapted from the instrument developed by Pieper^7,22 for use in this study. The instrument consisted of demographic questions, questions about extracurricular activities undertaken to learn about pressure ulcers, and the Pressure Ulcer Knowledge Test. The demographic items included sex, age, race, and academic year classification. In addition, information was obtained about participation in extracurricular learning activities, such as attending conferences or special lectures about pressure ulcers, reading articles and/or books about pressure ulcers in addition to materials assigned by the faculty, and using the home page about pressure ulcer prevention and treatment. The Pressure Ulcer Knowledge Test^7,22 was translated and adapted to Portuguese. After the initial translation, it was re-translated to English to validate that the items were the same as the translation. To examine the instrument for clarity and comprehension, eight students who did not participate in the study completed the instrument. These students reported no difficulty in reading or understanding the items. Content of the test was considered basic care for nursing practice. In its adaptation to Portuguese, 46 of the original 47 questions were maintained. The item related to vascular boots was deleted because this product was not used in Brazil. The item about heel protectors was modified to reflect the practice in Brazilian hospitals of placing water-filled gloves on the heels. Water-filled gloves are viewed as an inexpensive method to decrease heel pressure. However, Williams²³ tested gloves filled with 260 mL of water and found heel pressures were higher on the gloves than resting on a mattress.

  The 46 questions on the Pressure Ulcer Knowledge Test included seven items about pressure ulcer staging, seven items about wound description, and 32 items about pressure ulcer risk. The items were answered as true or false; items the students did not know were considered incorrect. Because the goal of the study was to examine total knowledge, items were tabulated for a total correct score. The coefficient alpha value for all students for the total score was .63.

  Procedures. The students present at the teaching institution on the dates established for data collection were invited to participate. They were assured that their identities would be kept secret and that the information provided would be confidential. Data collection proceeded with the students' completion of the instrument, which took approximately 20 minutes. The data were submitted to analysis after they had been transcribed to electronic tables using the EXCEL and EPI-INFO applications.

  Data analysis. The sample of students and number of correct responses for an item were described using percentages and frequencies. The Mann-Whitney U test was performed to examine difference between groups.

Results

  Subjects. From the 83 subjects comprising the sample, 53 (63.9%) were in the third year and 30 (36.1%) were in the fourth year of the undergraduate program (see Table 1). Most participants (38.6%) were 21 years old or younger (75.9% of the total number of students were 23 years old or younger), Caucasian (89.2%), and female (96.4%). Only two students had work experience as nurses in the position of a nurse auxiliary or technician. Third- and fourth-year students did not differ by age or sex.

  Pressure ulcer knowledge. The first research question examined students' knowledge about pressure ulcers. Students correctly answered 67.7% of the Pressure Ulcer Knowledge Test items (M = 31.16, SD = 4.19, range 20 to 41). No items were answered correctly or missed by all students. Of the 46 items, only 26 (56.5%) were answered correctly by 71.1% to 98.8% of students. Items with 90% correct responses (a high knowledge level) included content about pressure educational programs, incontinence, documentation, and nutrition, to name a few (see Table 2). In contrast, 20 items (43.5%) were answered correctly by 60.2% to 13.3% of participants. Items with the lowest correct scores (poor knowledge, with less than 50% of students responding correctly) included many time-related items about repositioning (see Table 3).

  Extracurricular learning activities, reading, and use of the pressure ulcer knowledge website. The second research question examined the impact of extracurricular learning activities, reading, and use of the Internet on the students' pressure ulcer knowledge. Sixty-three (63, 75.9%) students participated in extracurricular activities related to pressure ulcers. Examples of extracurricular activities are presented in Table 4. Sixty-five (65, 78.3%) students had read articles, texts, or books on pressure ulcers during their undergraduation studies. Among the material cited were texts provided in courses and journal club, dissertations or theses, bandaging manuals, and medical and surgical nursing textbooks. Twenty-one students (21, 25.3%) utilized the website on the prevention and treatment of pressure ulcers; 17 of the students used it two to five times.

  Students who participated (M = 31.71, SD = 4.37) in extracurricular activities had significantly higher Pressure Ulcer Knowledge scores than those who had not (M = 29.4, SD = 3.05; Mann-Whitney non-parametric z = -3.83, P < .001). The higher number of correct answers on the Pressure Ulcer Knowledge Test was associated with use of the website (M = 33, SD = 4.74) as opposed to those who had not used the Internet (M = 30.9, SD = 3.69; Mann-Whitney non-parametric z = -2.29; P = .02) (M = 33, SD = 4.1). In contrast, students who had read textbook or journal articles about pressure ulcers did not have significantly higher Pressure Ulcer Knowledge Test scores compared to those who had not consulted these sources.

  Students' comments. Forty-nine students provided comments about participation in the study. Students considered taking the Pressure Ulcer Knowledge Test an important way to evaluate their theoretical and clinical practice knowledge about pressure ulcers. They stated that knowledge tests such as this may contribute to the improvement of undergraduate nursing education programs. They commented that attending extracurricular lectures and seminars about pressure ulcers enhanced their knowledge. Students did not write comments about the Internet as a learning tool.

Discussion

  This study examined Brazilian nursing students' knowledge of pressure ulcers and practices that may enhance this knowledge. Generally, students were found to have low Pressure Ulcer Knowledge Test scores. Students' scores were higher if they had participated in extracurricular activities about pressure ulcers or used the website about pressure ulcers. The test included pressure ulcer nursing care practices that were clearly outdated and incorrect and which are still used by nurses in Brazilian hospitals and prescribed by physicians. Students are novice practitioners; learning in environments that espouse proper care is important. Lamond and Farnell²⁴ studied expert and novice nurses' decisions about the treatment of pressure ulcers. Nurses were given a photograph of a pressure ulcer along with descriptive information. Experts were more accurate in their choice of treatment and focused on specific information to make the decision. Possibly, the low scores of these students reflect their novice level of knowledge. Nevertheless, the low knowledge level about pressure ulcers is a concern. Fernandes²⁵ stated that the success of pressure ulcer prevention in hospitalized patients greatly depends on the education of healthcare professionals, patients, and their relatives for the adoption of and adherence to adequate measures. Although in its infancy in Brazil, this statement also holds true for home care, because many patients at risk for developing ulcers or who have ulcers are presently receiving care from relatives at home. Nurses in the basic (community) health units must provide guidance to these family members.

  Nurses must be able to seek relevant information about pressure ulcer prevention and care. Textbooks may not be up-to-date because of the potential delay between writing and publishing. In addition, content ages as students use the books over time.

  Thirteen nursing journals are published in Brazil with articles written in Portuguese. Because of the cost of paper and printing, these journals are limited in size and numbers of issues per year. This limits the venue for nurses to obtain new information. Universities subscribe to many international nursing journals, but Brazilian nursing students primarily speak and read Portuguese; thus, limiting available information. Information in journals and textbooks needs to be useful for the decisions made about pressure ulcer prevention and treatment, and currently available research does not appear to reach the nurses who make decisions about patient care at the bedside. Gould²⁶ noted nurses' failure to implement research results and related this to the failure of nursing faculty to include relevant materials in educational programs. Globally, the lack of research implementation also must be examined in terms of language and resource barriers.

  Attending extracurricular activities such as special lectures and courses requires motivation. Students at this university in Brazil had opportunities to participate in special courses and lectures about wound care and pressure ulcers. These programs featured local and international experts in pressure ulcer and wound care. Students selected these programs because of a special interest in the topic; they paid a fee to attend these programs. They were active participants in the learning process. Students who attended these programs had a higher level of pressure ulcer knowledge, underscoring the fact that education about pressure ulcer prevention and wound care is a life-long effort, requiring active engagement of the learner.

  The Internet provides worldwide information to students. Web-based instruction requires transformation from traditional teaching strategies to directed independent learning.²⁷ Teikmanis and Armstrong²⁸ used an online discussion board to teach pathophysiology to baccalaureate nursing students. Their results suggested that this assignment promoted greater participation and feedback among students. Because of the cost, computers are not generally owned by Brazilian nursing students, but they are available at university libraries. Internet sites expose students to a variety of information because of links within the system. The student is an active participant in making decisions about the depth and breath of the content presented. The most recent literature also can be examined. Although few students (n = 21) used the Internet, those who did had higher knowledge scores. The Internet will probably continue to evolve as an important educational tool for pressure ulcer information.

Limitations

  This study had limitations. The sample size was small and students from only one university were participants. The Pressure Ulcer Knowledge Test needs further testing with students in Portuguese because the reliability was .63. This may be a reflection of the nature of items on the test or the way it was administered. Students may not have considered items carefully because the test did not affect their course grade. The study needs to be replicated with a larger and more diverse sample. Examining students' nursing practice with knowledge is critical. These graduates primarily direct patient care provided by other levels of nursing personnel in Brazil. If they lack the necessary knowledge about pressure ulcer prevention, assessment and care, the information they give to others will be insufficient.

Conclusion

  Nursing professionals must be educated to intervene positively in the process to prevent and treat pressure ulcers. To that end, knowledge and skills both for direct care to the patient and management of human resources and materials are necessary; hence, the importance of quality theoretical and practical teaching. Knowledge about pressure ulcer prevention and treatment must be achieved in undergraduate educational programs where students must gain knowledge and skill to provide safe patient care in regard to maintaining skin integrity. Pressure ulcer risk assessment based on knowledge of risk factors, prevention, and early intervention is crucial to decreasing pressure ulcers.²⁹ Research-based nursing practice is frequently stressed in educational endeavors. Research utilization activities with students about pressure ulcers may lead to positive outcomes in pressure ulcer prevention, just as it has in clinical settings.³⁰ Continuing educational programs and use of the Internet have the potential to positively impact nursing students' knowledge. - OWM

Acknowledgments

  The authors wish to thank Dr. Claudia B. dos Santos for the statistical analysis of the data and Dr. Miyeko Hayashida for her assistance in the use of the EPI-INFO program.

  This study was partially supported by grants from Fundacao de Amparo a Pesquisa do Estado de Sao Paulo - FAPESP (Proc. No. 2000/05458-5) and Conselho Nacional de Desenvolvimento Cientifico - CNPq (PIBIC/USP).

Ms. Caliri is Associate Professor and Ms. Miyazaki is a former BSN nursing student, Ribeirao Preto School of Nursing, University of Sao Paulo, Ribeirao Preto, Brazil. Dr. Pieper is a Professor/Nurse Practitioner, College of Nursing, Wayne State University, Detroit, Mich. Please address correspondence to: Maria Helena Larcher Caliri, DNS, RN, Assistant Professor, Ribeirao Preto School of Nursing, University of Sao Paulo, Ribeirao Preto, SP 14040-902, Brazil; email: mhcaliri@eerp.usp.br.

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