How should bladder sensation be measured?: ICI-RS 2011

Postoperative Urinary Retention

ABSTRACT

This clinical consensus statement on the management of postoperative (<6 weeks) urinary retention (POUR) reflects statements drafted by content experts from the American Urogynecologic Society's POUR writing group. The writing group used a modified Delphi process to evaluate statements developed from a structured literature search and assessed for consensus. After the definition of POUR was established, a total of 37 statements were assessed in the following 6 categories: (1) incidence of POUR, (2) medications, (3) patient factors, (4) surgical factors, (5) urodynamic testing, and (6) voiding trials. Of the 37 original statements, 34 reached consensus and 3 were omitted.

Methods of assessing and recording bladder sensation: a review of the literature

Introduction and hypothesis

The objective was to review different methods that have been used to assess bladder sensation and to provide an overview of the accuracy and objectivity of the measurement of the subjective perception of the bladder.

Methods

The MEDLINE and PubMed databases were searched to identify articles. References from those articles were also searched. Terms used for the search were: urinary bladder, sensation, cystometry, urodynamics, urinary incontinence and focus group. Eight hundred and fifty abstracts were identified from databases, and 12 from other sources. Twenty-two duplicate articles were removed. Irrelevant articles were excluded after reading their titles. Fifty-four articles were eligible, but 17 were excluded after reading the full text, leaving 37 articles where assessment of bladder sensation was the main aim.

Results

Six different methods of measuring bladder sensation have been described in the literature. Although the most frequently used was cystometry, this is an invasive tool and does not reproduce bladder behaviour during daily life because it records bladder sensation as episodic events. The visual analogue scale using a forced diuresis protocol seemed to be an excellent tool. It was non-invasive and evaluated bladder sensation continuously, from an empty to a full bladder.

Conclusions

In some of the studies, the samples were too small to draw any significant conclusions. There were also conflicting data on which tool was the most accurate, especially as each method of evaluating bladder sensation may influence the way it is described by participants.

Validation of a water-load protocol to define the pattern of bladder sensation

Introduction and hypothesis

The aim of this study was to confirm reliability of a water-load diuresis protocol and to assess the utility of bladder sensation curves.

Methods

For confirmation of fixed diuresis rate (phase 1), 12 volunteers consumed 250–300 ml of water every 15 min and recorded bladder sensation on a visual analogue scale (VAS) every 5 min to maximum sensation over two filling cycles: voids 1 and 2 (V1 and V2). The test was performed twice. For test–retest validation (phase 2), 24 participants underwent the same protocol drinking 300 ml of water every 15 min. Diuresis rates and voided volumes were compared between cycles and across tests.

Results

In phase 1, there was no difference in median void volume (V1 735 ml, V2 678 ml p = 0.433) or median diuresis rates (V2 12.1 ml/min, V3 14.4 ml/min p = 0.136) between cycles. When comparing those who drank 250–300 ml/15 min, there was less variability in those drinking 300-ml aliquots, so this was standardised for later experiments; 95% upper confidence limit of variability of the diuresis rate was calculated as 4.5 ml/min. Any test with a greater difference was rejected as invalid. In phase 2, only 16 participants were analysed. There was no difference in median void volumes between tests [V1 763 ml and 820 ml (p = 0.109) and V2 788 ml and 796 ml (p = 0.266)] or in diuresis rates between test 1 (12.33 ml/min) and 2 (14.40 ml/min) (p = 0.056). Median area under the curve was similar between test 1 404.96 and test 2 418.63.

Conclusions

This refined protocol reliably produced stable diuresis with a water load of 300 ml/15 min, excluding those with a difference in diuresis rate > 4.5 ml/min.

NEW CONCEPTS IN BLADDER SENSATION AND URINARY URGENCY

PURPOSE OF REVIEW

The purpose of this review is to summarize the current state of knowledge regarding the evaluation and measurement of urinary urgency and bladder sensation.

RECENT FINDINGS

New technologies have been developed to improve our diagnostic capabilities in urinary urgency and bladder sensation. Recent developments include MRI-based neuroimaging and novel tablet-based sensation meters that can be used during urodynamics as well as during oral hydration.

SUMMARY

Commonly used metrics for urinary urgency and bladder sensation include the use of validated surveys/void diaries and standardized verbal sensory thresholds during urodynamics. However, these metrics are highly subjective and prone to significant bias. There has been an evolution in evaluation metrics ranging from the use of reflex testing to electrical perception testing to the use of neuroimaging and the development of sensation meters. Neuroimaging allows for mapping of specific brain areas involved in the different phases of voiding and provides an anatomic basis for different forms of overactive bladder. The sensation meter allows for generation of real-time sensation-capacity curves which enables easy and objective comparison between patients as well as potential sub-typing of different forms of overactive bladder. In addition, new research supports the concept of differing forms of urgency and the use of novel patient-derived terminologies for urinary urgency and bladder sensation.

Quantification of bladder wall biomechanics during urodynamics: A methodologic investigation using ultrasound

Overactive bladder is often characterized by biomechanical changes in the bladder wall, but there is no established method to measure these changes in vivo. The goal of this study was to develop a novel method to determine detrusor wall biomechanical parameters during urodynamics through the incorporation of transabdominal ultrasound imaging. Individuals with overactive bladder (OAB) underwent ultrasound imaging during filling. The fill rate was 10% of the cystometric capacity per minute as determined by an initial fill. Transabdominal ultrasound images were captured in the midsagittal and transverse planes at 1min intervals. Using image data and Pves, detrusor wall tension, stress, and compliance were calculated. From each cross-sectional image, luminal and wall areas along with inner perimeters were measured. In the sagittal and transverse planes, wall tension was calculated as Pves∗luminal area, wall stress as tension/wall area, and strain as the change in perimeter normalized to the perimeter at 10% capacity. Elastic modulus was calculated as stress/strain in the medial-lateral and cranial-caudal directions. Patient-reported fullness sensation was continuously recorded. Data from five individuals with OAB showed that detrusor wall tension, volume, and strain had the highest correlations to continuous bladder sensation of all quantities measured. This study demonstrates how detrusor wall tension, stress, strain, and elastic modulus can be quantified by adding ultrasound imaging to standard urodynamics. This technique may be useful in diagnosing and better understanding the biomechanics involved in OAB and other bladder disorders.

Assessing multiple dimensions of urgency sensation: The University of South Australia Urinary Sensation Assessment (USA2 )

AIMS

To develop and assess structure, test-retest reliability, and discriminative validity of a self-report questionnaire (University of South Australia Urinary Sensation Assessment: USA² ) to assess multiple dimensions of urgency sensation.

METHODS

The USA² was designed and tested over two prospective, observational studies (2013-2014). Participants were English speaking Australians aged 50 or more with and without overactive bladder (OAB; determined by OAB awareness tool), recruited via health and recreation centers. In Study 1, exploratory factor analysis determined USA² structure and subscales. In Study 2, confirmatory factor analysis reassessed structure; Mann-Whitney U-tests determined discriminative validity (OAB vs. non-OAB for subscale and total scores) with Cohen's d effect sizes. Thirty-three individuals completed the USA² twice; intraclass correlation coefficients (ICCs) and Wilcoxon signed rank tests assessed test-retest reliability.

RESULTS

Questionnaires were returned by 189 eligible participants in Study 1 and 211 in Study 2. Exploratory factor analysis revealed three subscales: "urgency," "affective," "fullness." Confirmatory factor analysis supported these subscales. Subscale and total scores were significantly different between groups with and without OAB (P < 0.001). Cohen's d effect sizes (95%CI) were total score 1.8 (0.5-3.1), "urgency" subscale 1.8 (1.3-2.3), "affective" 1.7 (0.95-2.4), and "fullness" 0.75 (0.42-1.09). Total and subscales scores demonstrated test-retest reliability; ICCs (95%CIs) of 0.95 (0.9-0.98), 0.96 (0.92-0.98), 0.94 (0.88-0.97), and 0.78 (0.56-0.89).

CONCLUSIONS

The USA² assesses multiple dimensions of urgency sensation, is reliable over a 2-week period, and discriminates between older adults with and without OAB. Further validation is required in conditions other than overactive bladder. Neurourol. Urodynam. 36:667-672, 2017. © 2016 Wiley Periodicals, Inc.

[Clinical and paraclinical evaluations of bladder sensitivity. Review of the literature]

INTRODUCTION

The aim of this work was to carry out a review of the literature on the clinical and paraclinical evaluation of bladder sensory (BS) to better understand BS disorders in nonneurological patients.

METHODS

Thirty-three articles were selected from the Medline(®) Database between 1992 and 2012 using the following key words: "sensory/sensitivity bladder evaluation", "sensory/sensitivity bladder scale", "sensory/sensitivity bladder questionnaire", "urodynamic bladder sensory", "urgency questionnaire" and "Overactive Bladder (OAB) questionnaire".

RESULTS

Evaluation of BS by asking questions during cystometry is validated (LE 2). The sensation of the desire to void progresses linearly with bladder filling (LE 2). Many symptoms and quality of life questionnaires related to BS anomalies have been proposed. Bladder diaries, frequency/volume curves (LE 2) and clinical algorithms (LE 3) could be an alternative to evaluate BS.

CONCLUSION

Current evaluation only provides a partial view of BS. A multidimensional approach should lead to better understanding of BS disorders.

Pathophysiology of idiopathic overactive bladder and the success of treatment: a systematic review from ICI-RS 2013

AIMS

To investigate the frequency of phenotype profiling of patients with idiopathic overactive bladder (OAB) syndrome, and to determine the effectiveness of treatment among individuals with different pathophysiologic profiles.

METHODS

The electronic databases MEDLINE, EMBASE, Cochrane CENTRAL, Cochrane Database of Systematic Reviews, and CINAHL were searched from January 1, 1980 to August 12, 2013 for interventional randomized controlled treatment trials (RCTs) of idiopathic OAB. Phenotying for pathophysiologies originating in the urothelial/mucosal layer of the bladder, the detrusor muscle cell layer, and the central nervous system were sought. Articles that analyzed urgency outcomes based on pathophysiologic profiling were selected. Due to the heterogeneity of the included interventions and outcome assessment measures, meta-analysis was not appropriate and a qualitative synthesis was undertaken.

RESULTS

Of 239 original RCTs of idiopathic OAB, 48 (20%) profiled participants on underlying pathophysiology. Less than half of these (n = 20) reported treatment efficacy for urgency symptoms by pathophysiological sub-type. One examined the effect of botulinum A toxin on interstitial cell protein expression. Four compared treatment efficacy in OAB patients with and without involuntary detrusor contractions. Fifteen compared the effect of treatment on urgency reduction in patients with detrusor overactivity. There were no consistent trends in treatment efficacy according to pathophysiologic sub-type. No studies examined urothelial dysfunction or abnormal central processing of bladder afferent signaling in response to treatment.

CONCLUSIONS

In order to advance the field of idiopathic OAB, more trials are needed that profile and test urgency outcomes in participants according to suspected underlying pathophysiology. Neurourol. Urodynam. 33:611-617, 2014. © 2014 Wiley Periodicals, Inc.