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An Evaluation of the Canadian Ostomy Assessment Guide

Empirical Studies

An Evaluation of the Canadian Ostomy Assessment Guide

Index: Ostomy Wound Manage. 2002;48(8):26-32.

   The Canadian Ostomy Assessment Guide (COAG) was developed to assist in the selection of appropriate pouching systems by nonspecialized nurses. With the reform of Canada's healthcare system, ostomy patients are discharged from hospital 5 to 7 days after surgery, limiting time for teaching. Furthermore, due a limited number of enterostomal therapists (ETs) in hospital and home care settings, ostomy patients are frequently taught and cared for by nonspecialized nurses who may have little to no knowledge about ostomy pouching systems. In response to this situation, as well as the limited evidence-based literature on the steps and sequence necessary to select an adequate pouching system for individuals with an ostomy, an Advisory Committee (AC) of 10 Canadian stoma care nurse-experts were brought together to reach consensus on best practice guidelines. The AC consulted the key literature available1-4 to develop a concise generic clinical tool, the COAG. The document is designed to assist in the selection of appropriate pouching systems by nonspecialized nurses. Since its development in 1999 until December 2001, 4,500 nurses across Canada have been trained to use COAG in their clinical practice. However, the effect of its use has not been studied. The purpose of this prospective cohort study was to evaluate the impact of COAG on the well-being of patients with ostomies. The specific objectives were to: (1) assess the effect on wear time of the ostomy pouching system; (2) evaluate changes in the peristomal skin status; (3) assess the financial impact on the overall cost of ostomy products; (4) assess overall patient perception of well-being and acceptance towards the selected ostomy pouching system; and (5) ascertain the usefulness of the COAG as a generic clinical tool for the non-specialized nurse. COAG Instrument The COAG consists of three algorithms: (1) colostomy and ileostomy, (2) urostomy, and (3) common peristomal skin problems. All three algorithms are contained in one laminated full-color, foldover, 8-inch by 10-inch tool. Full-color illustrated annotations with references are contained in an accompanying binder. Each algorithm has similar features that compose its unique structure (see Figure 1). An icon section at the top of each algorithm contains a group of graphic symbols representing specific components of the pouching system - eg, a one-piece pouching system (ie, icon 17) or a two-piece system (ie, icon 18). The algorithm also contains a list of assessment criteria with color codes and numbers to facilitate a quick reference in the right section of the annotations. Each criterion has a question(s) to confirm clinical findings to the user. If no potential problem is detected, the user is directed down to the next criterion or across to the next criterion to select adequate pouching features to address this specific need of the patient's stoma characteristic or psychosocial profile. When the nurse has completed the process, the features of an appropriate pouching system for the individual are listed. Methods After obtaining study approval from the Health Research Ethics Board of the University of Alberta in Canada, this prospective cohort study commenced in June 1999 and was completed in January 2000. Members of the AC recruited and trained 18 nonspecialized home care nurses across Canada as nurse investigators, who, in turn, recruited patients for the study. ConvaTec Canada provided each nurse investigator with samples of its complete ostomy product line for use during the study to ensure uniformity. All of the 18 nurse investigators attended an educational session on use of the COAG before their participation in the study. The educational session ranged from 4 hours to a full day seminar. However, before starting the study, each ET nurse who recruited nonspecialized nurse investigators in their respective region met with them and reassessed (via case studies or other means) their comprehension and ability to use the COAG adequately. Any remaining questions concerning the study were addressed; once the nurse investigators were out in the field, they could direct questions to the ET nurse responsible for their region.

   Target population. Patients eligible for enrollment had to have a colostomy, ileostomy, ileal conduit, or ureterostomy and be at least 2 weeks post surgery. Patients who had been assessed by an ET nurse within the past 6 months and patients who were not receiving community care (home care) during the duration of the study were not eligible for study participation.

   Measures and instruments. Each patient was assessed a total of three times during the study: an initial assessment (t0), a follow-up assessment scheduled 1 week after the initial visit (t1), and a final assessment 2 weeks after the follow-up visit (t2). Patients who experienced problems were instructed to call the nurse investigator and the next visit would be moved up to address the problem. At each visit, the nurse investigator removed the pouching system and assessed the patient's stoma using the appropriate COAG algorithm. Peristomal skin status was assessed at criterion number five of the algorithm (See Figure 1). If the peristomal skin was not intact, the nurse listed the problems on a data form. She then applied the selected ostomy products indicated by COAG and provided patients with duplicate sets of products in the event leakage occurred before the next scheduled visit. On a data collection form, the nurse investigator recorded all COAG-selected products. Upon completion of the study, the study coordinator reviewed the data to determine nurse compliance. Compliance was defined as use of the recommended product options for all of the COAG criteria. Noncompliance was defined as failure to select the recommended product options for any of the assessment criterion on the COAG. To evaluate pouching system wear times at baseline (t0), patients estimated the average number of days their system lasted. For the final assessment (t2), pouching system wear time between t1 and t2 was calculated. The cost-effectiveness aspect rather than the unit cost of the pouching system was considered because it reflects more adequately the annual expenditures for ostomy products. The mean cost per day was calculated by dividing the sum of product unit costs used during the study by the number of days the pouching system remained in place. Costs per day at baseline (t0) were calculated using the same method. Costs were calculated in Canadian dollars. Patients also completed a quality of life (QOL) questionnaire at each visit. Because the study team believed that a patient's perception of pouching system performance could not be achieved using a general validated quality of life tool, the study coordinator developed a nine-question document that was reviewed by all of the ETs who were part of the AC. Using a 5-point Likert scale, patients answered questions related to concerns about their pouching system (wear time, ease of application, lifestyle, security, comfort, appearance, and fear of leakage), life style, and quality of life. After completing the study, each nurse investigator completed an End of Study Evaluation about the usefulness of the COAG as a generic clinical tool using a 5-point Likert scale.

   Data analysis. Data analysis was performed using SAS(R) statistical software (SAS Institute Inc., Cary, NC). Descriptive statistics were used to summarize all data. A paired t-test was used to analyze differences in the mean wear time of the pouching system, peristomal skin status, appliance cost per day, and quality of life scores. A chi-square test was used to assess whether nurse compliance to COAG influenced the peristomal skin status. Results Fifty patients (26 men, 24 woman) with a mean age of 69 were enrolled in the study. The majority of patients had a permanent stoma (62%) following a diagnosis of cancer (46%) (see Table 1). The nurses' baseline (t0) compliance with the COAG was 56%. During the study, compliance increased to 73% at t2 (see Figure 2). Pouching system wear time increased from a mean of 4.2 days at baseline (t0) to 5.7 days at the final visit (difference 1.5 days, paired t-test P <0.001) (see Figure 3). Peristomal skin problems were observed in 42% of the population at baseline (t0), in 48% at the follow-up visit, and in 44% at the final assessment visit (t2) (see Figure 4). This difference was not significant. Skin problems also did not differ significantly between compliant and noncompliant nurse investigators. The sample size was too small to identify study outcome differences between colostomy, ileostomy, and urostomy patients. The cost per day of the ostomy products at baseline (t0) was $4.70 and $2.90 at follow-up (a difference of $1.80, paired t-test, P < 0.05) (see Figure 5). Both the compliant and noncompliant groups exhibited a decrease in daily expenditures. An attempt was made to compare outcomes between the skin status at the follow-up visit (t1) and the mean wear time as well as the mean cost per day; the results were statistically inconclusive. With the exception of question 8 (see Table 2), all patient scores within the quality-of-life questionnaires improved significantly between t0 and t2. Satisfaction with the appearance of the ostomy pouching system under clothing scores (Q6) improved the most (paired t-test, P < 0.001) (see Table 2). Of the nurse investigators, 67% believed that the COAG was extremely useful (score 5) and 11% rated it as a very useful tool (score 4). Eight nurse investigators stated they were proud to have participated in this study because they felt that using COAG could make a difference in their patients' lives. They also said the tool enhanced their knowledge of ostomy care. Some ostomy patients felt an increase in assurance when they observed the nurse using a systematic tool to evaluate their needs. Discussion In this study, using the COAG increased appliance wear time an average of 1.5 days, reduced cost by $1.80 (Canadian) per day, and improved patients' overall sense of comfort and well-being. Although application of the pouching system by a nurse and resultant attention to the patient's needs may have biased the study (eg, increased wear time and improved sense of well-being) during the study period (between t1 and t2), the patient or caregiver often reapplied the system themselves because a period of 14 days was scheduled between the two visits. The short follow-up period (19 days), relatively small sample size (50), and absence of a detailed peristomal skin data collection form did not enable observation of significant changes in peristomal skin. The nurse investigators were instructed to only record if the peristomal skin was intact or not; no data related to skin condition improvement or deterioration were recorded. Pouching system wear times improved in both compliant and noncompliant groups. Although the definition of noncompliance was strict, this finding suggests that even suboptimal usage of the COAG may help ostomy patients. The $1.80 reduction in the average daily costs of ostomy appliances is significant both at the personal patient and national payor levels, because this represents a savings of more than $600.00 per year - an amount equal to the annual government funding for a permanent ostomy in some provinces in Canada. The broad implementation of this generic clinical tool with generalization of the study results to nonspecialized nurses should be considered with caution, as nurses participating in the study may have had an increased motivation simply by their involvement in the study. Nevertheless, the study outcomes clearly demonstrate the importance of adequate education in using the COAG. Any noncompliance in using the COAG will negatively impact patient outcomes. Conclusion The results of the COAG study demonstrated major benefits for ostomy patients when nonspecialized nurses use this generic clinical tool to select an appropriate pouching system. Key results of the study include: an increase in the mean wear time of the ostomy pouching system of 1.5 days from baseline, a decrease in the overall cost of ostomy products by $1.80 per day, significant changes in QOL domain scores, and the finding that 78% of nurse investigators felt that the COAG was a useful tool in their clinical practice. Because clinical outcomes were influenced by nurses' compliance, COAG education and training is important. Finally, the observed reduction in costs may help individual patients, as well as provide important information for government, private agencies, and insurers.

   The Canadian Ostomy Assessment Guide was developed under the sole sponsorship of ConvaTec, a Division of Bristol-Myers Squibb Canada Inc., which holds the copyright and all reproduction rights. The Canadian Ostomy Assessment Guide may not be reproduced in any manner. To attend an educational program, or obtain more information on the Canadian Ostomy Assessment Guide, please email ConvaTec Canada at

   The author wishes to acknowledge the collaboration of colleagues who were part of the AC and developed the COAG and/or for their involvement in the research project in their region. They include Sandra Allen, RN, ET, University of Alberta Hospital; Ruth Best, RN, BA, ET, London Health Science Center- Victoria Campus; Jean Chambers, RN, BN, ET, SMBD Jewish General Hospital; Ardis Granger, RN, ET, East Regional Health Authority # 7; Gail Hawke, RN, ET, Nightingale Medical Supplies; Gay Hordienko, RN, BN, ET, Manitoba Ostomy Program; Manon Paquin, RN, BSc, ET, Centre Hospitalier de l'Universite de Montreal- Campus St-Luc; Nancy Parslow, RN, ET, independent practice; Gwen B. Turnbull, RN, BS, CETN, Consultant and Carla Wells, RN, BScN, MN, ET, Western Health Care Corp. The author also would like to acknowledge the participation of the following nurses as investigators in the research project: Debra Gail Adams, RN; NOHR, and Daravan Banghit, RN, CLSC St-Michel; Denise Bond, RN, VON Antigonish, and Pauline Choquette, RN, CLSC La Pommeraie; Anne Clarke, RN, Home Care Wetaskiwin; Irlene Douyon, RN, CLSC Villeray; Chantal Drolet, RN, CLSC Ahuntsic; Bonnie Flood, RN, VON Brant Norfolk Haldimand; Anne Ford, RN, Crossroads RHA Home Care; Diane Fugère, RN, CLSC La Pommeraie; Valerie Gomes, RN, Grey Nuns Community Hospital; Shelley Jollota Kaiser, RN, Home Care Nova Scotia; Joan Johansen, RN, VON Durham Region; Maureen Long, RN, Department of Health Home Care; Heather McCurdy, RN, VON Truro Branch; Elizabeth Newman, RN, VON Brant Norfolk Haldimand; Brenda Ogle, RN, VON Durham; Angela Samson, RN, Bayshore Health Care; Tammy Schroeder, RN, Sturgeon Community Health Centre; Judy Symington, RN, NORHB; Bonnie Taylor, RN, Salmon Arm Community Care; Mona Teed, RN, VON Truro Branch; Christine Thibault, RN, CLSC Villeray; and Johanne Vallée. RN, CLSC St-Michel.