Post-operative Voiding Dysfunction: the Preferred Method for Catheterization

Method PART 1 For the first part of the study, patient preference between TIC, CISC, SPT will be assessed during a face-to-face interview after the patient has had sufficient time to read the information sheet about the three options available and has had the opportunity to ask questions. This will ensure that every patient will receive the same information. The face-to-face interview will be performed by the patient's physician or by one of the two urogynecology nurses working at the St. Michael's Hospital Women's Health Care Centre. The patient's choice will be recorded in the pre-operative record and then in the study database by one of the study personnel.

Other data collected will include patient demographics (age, education level, level of home support, current or past occupation), clinical characteristics (BMI, parity, International Continence Society (ICS) stage of prolapse, and any pre-operative urinary diagnoses) (Appendix 4).

Peri-operatively, data collected will include the surgery performed, the length of hospital stay, and the occurrence of any peri-operative complications. At our institution we have defined normal voiding function as having a voided volume of > 200 mL with a post-voided residual (PVR) of < 100 mL or having a voided volume of > 400 mL with a PVR of < 33% (1/3) of the total voided volume. Patients have to meet these criteria on two separate voids while in hospital or they will be classified as having post-operative voiding dysfunction. Once they meet the criteria for voiding dysfunction, then the method of bladder drainage used (TIC, CISC and SPT) and the length of time it was used for will be recorded.

To reduce the rate of bacteriuria and other signs of bladder infection [25], antibiotic prophylaxis will be administered as usual to all patients that require bladder drainage for more than 24 hours. The antibiotic regimen consist of: Macrodantin 100 mg PO daily for the time of the bladder drainage, or Trimethoprim 100 mg PO daily if allergic. This is the regimen currently being used in our department.

For those patients that underwent catheterization in the post-operative period, satisfaction with regard to catheter management will be assessed using a visual analog scale based on a previously published questionnaire. This questionnaire will be administered on the day of discharge, on post-operative day seven, and six weeks after surgery. Post-operative bladder function in those that required catheterization will be assessed on post-operative day seven and six weeks after surgery using uroflowmetry testing, PVR measurement, and a specimen for urine culture.

PART 2 Women that were consented for the second part of the study will be randomized to either pre-operative CISC teaching in the clinic or post-operative CISC teaching in the hospital. A computer-generated list of random numbers will be used to allocate participants into 2 groups of equal size. To ensure consistency in teaching patients on CISC, nurses in the clinic and in the hospital will use the same protocol for instruction of CISC.

Patients allocated to the pre-operative CISC teaching group will be taught how to perform CISC by one of urogynecology nurses working at the Women's Health Care Centre. Patients will be allowed to practice until they feel comfortable with the technique. This should take approximately 30 minutes. The session will take place on the day of their pre-operative medical appointment (PAF), which normally occurs less than a month before the surgery. If a patient is not seen in PAF or is seen more than a month before her surgery, a separate appointment for CISC teaching during the month preceding the surgery will be organized. Post-operatively, a nurse from the hospital gynecology unit will review the technique to make sure the patient is still comfortable with performing CISC.

Patients allocated to the post-operative CISC teaching group will be instructed on CISC after surgery, starting on post-operative day one. One of the nurses from the hospital gynecology unit will teach and supervise the patients until they feel comfortable with the technique or until catheterization is no longer required (e.g. when the patient passes her voiding trial on two separate occasions). This is the protocol currently in use at our institution.

Patients in both groups will have to be comfortable and independent in performing CISC prior to being discharged from the hospital. Following their discharge, a nurse from the Women's Health Care Centre will be available to answer any questions by telephone.

For both groups, satisfaction will be assessed with a questionnaire that will be administered on the day of discharge, on post-operative day seven, and six weeks after surgery. Assessment of post-operative bladder function in those that required catheterization will occur on post-operative day seven and six weeks after surgery using uroflowmetry testing, PVR measurement, and a specimen for urine culture.

Patients with no post-operative voiding dysfunction will be withdrawn from the study. Since it is impossible to predict who will experience post-operative voiding dysfunction, it is essential to recruit all potential participants prior to surgery so that they can receive pre-operative CISC teaching if allocated to this group. Pre-operative data, however, will be kept for all recruited patients for the purose of study analyses.

Data analysis PART 1 Demographic measures, catheterization choice, and clinical data will be summarized using descriptive statistics. Patient satisfaction will be assessed using questionnaires that will be reviewed and scored. The questionnaire has 6 items and each item consist of a 10 cm line visual analogue scale. Patients will be asked to put an "X" on this line between the 2 extremes. The distance from the beginning of the line to the patient's X will be measured and the score will be obtained. Scores will be calculated by adding the scores of the 6 items (range 0 to 60), then dividing by 6 and multiplying by 10. Missing items are dealt with by using the sum from answered items only, dividing by the number of items answered. Patient who answered fewer than 4 questions will not be considered in the analyses.

PART 2 As above, demographic measures and clinical data will be summarized using descriptive statistics. Each of the questionnaires will be reviewed and scored. For this part of the study, the questionnaire has been modified with the addition of three items with a response scale score of 0 to 10. Scores are calculated by adding the scores of the 9 items (range 0 to 90), then dividing by 9 and multiplying by 10. Missing items are dealt with by using the Sum from answered items only, dividing by the number of items answered. Patient who answered fewer than 6 questions will not be considered in the analyses. Each of the questionnaires will be reviewed and scored. Satisfaction scores between the two groups (pre-operative and post-operative teaching) will be compared using a two-sided Student's t-test.

For both parts of the study, continuous variables will be summarized as means (standard deviation) or medians (minimum, maximum) and compared between groups using Student's t-tests or Kruskal Wallis tests. Categorical variables will be summarized as counts (percent) and compared between groups using Fisher's exact tests.

Sample Size Calculation For the first part of the study, we are aiming to survey a minimum of 150 patients. The power calculation for the second part of the study is based on a previous study [11]. Based on these findings, we defined the minimal relevant difference in patient satisfaction with regard to CISC teaching to be 30% with a standard deviation of +/- 30. With a power of 0.8 and an alpha of 0.05, the minimum number of patients required in each group is eight. We anticipate a 10% drop out rate after consent and we expect that 65% of patients will not require any form of outpatient catheterization after their surgery. Therefore, we will require 25 patients per arm for the second part of the study. Recruitment for the first part of the study will cease once we have recruited all the patients required for the second part or once we have recruited 150 patients, whichever comes first.

Timeline for completion Based on the operative hospital data from 2010, we will need approximately 24 months to recruit patients and collect data. Three more months will be required for data analysis and manuscript preparation.