Hypothesis / aims of study
An intravesical catheter may be associated with an urge to void, suprapubic pain and/or urine leakage, causing significant distress to the patient, although the incidence of such symptoms is unclear.
Existing tools available to assess the severity of symptoms related to the bladder catheter are inaccurate, may not help in the differential diagnosis with postoperative pain and are not standardized, compromising a proper comparison between treatments.
Thus, this study aimed to verify the applicability of a Catheter-Related Bladder Discomfort Questionnaire, a new measurement tool for evaluation of LUTS in patients with indwelling catheters.
Study design, materials and methods
A questionnaire was designed in order to assess the severity of symptoms as well as its impact on the quality of life.
It consisted of two numeric rating scales (NRS), one ranging from 0 to 100 points and another from 0 to 10 points to assess suprapubic discomfort, which has been used generically in previous studies. A modified version of Overactive Bladder Questionnaire short form was added, taking into account the similarities between overactive bladder and catheter-related bladder symptoms. Four visual analogue scales from Urgency Questionnaire were also used, as well as two questions concerning quality of life based in the International Prostatic Symptom Score (IPSS). The final part consisted in a questionnaire about the difficulties on filling the form.
A retrospective, observational, transversal study was conducted. The Catheter-Related Bladder Discomfort Questionnaire was applied to patients admitted for elective surgery in General Surgery and Orthopedics Departments of a tertiary hospital, over a period of 18 months. Patients with pelvic surgery were excluded. A comparison of the questionnaire results between catheterized and non-catheterized patients was performed.
Our primary endpoint was to verify the applicability of this new tool in order to properly assess catheter-related bladder symptoms. The statistical analysis was performed with SPSS®v24.
A total of 122 patients were asked to complete the questionnaire, along with Assessment of Difficulty of Filling questionnaire. Mean age was 53,9 ± 19 years-old and 55% were female.
54/122 patients (44,3%) had an intravesical catheter. There were no differences concerning demographic baseline characteristics and level of literacy among patients with a catheter or without it.
When evaluating suprapubic discomfort, there was a good correlation between NRS 10 and NRS 100 (rs=0,697), however there was no statistically differences between catheterized and non-catheterized patients. OAB questions presented an adequate internal consistency, as well as visual analogue scale items (Cronbach’s alpha coefficient=0,865 and 0,908, respectively). The only parameter with a difference statistically significant between catheterized and non-catheterized patients was the visual analogue scale (p=0,011).
In a scale ranging from 1 to 6, the mean filling the questionnaire difficulty was 2,85, with only 22 patients considering it “difficult” or “extremely difficult”.
Interpretation of results
The present evaluation of catheter-related bladder discomfort is based on unspecific and non-validated scales, developed for similar conditions. Therefore, symptom presence and severity may be inaccurately assessed. As a result, clinicians may fail to identify catheter-related bladder discomfort, not offering adequate treatment.
The Catheter-Related Bladder Discomfort Questionnaire was aimed to evaluate the whole spectrum of symptoms the patient might present in an objective and reproducible manner. By evaluating the impact on quality of life, such tool may be used in the daily practice, taking part in the decision whether to maintain a catheter chronically or to decide the type of urinary diversion (suprapubic versus urethral). Likewise, it can be used in clinical investigation.
Although adequate internal consistency was shown, there were no statistically significant differences between patients with an intravesical catheter when compared to those without a catheter, except for the visual analogue scale.
Some study limitations may have contributed to the results found, including: small number of patients included, different anesthesia and analgesic protocols used and lack of additional specific domains that could help to differentiate between patients with or without an indwelling catheter.
By using only questions with more favorable respondent feedback, as determined by the difficulty in filing the form, the questionnaire may be more succinct and allow, for instance, for extra-catheter urine leakage or urethral pain to be also properly addressed by additional questions.
Future studies are needed to allow a more adequate tool to be designed for this purpose.