Development and first-in-human testing of FLUME urinary catheter with protected tip and relocated drainage holes.

Purpose: Evaluation of a catheter design which protects its tip with the retaining balloon when inflated, and has eyeholes at the base of the balloon to improve drainage. Materials and methods: Preclinical tests included assessment of retaining balloon performance, and microbiological blockage. Clinical testing evaluated short-term use and safety in hospital (stage 1) or the patient's usual residence (stage 2). Results: The retaining balloon supported static loads of 0.7kg, with reduced trauma when modelling forced evulsion. In vitro time to blockage with P. Mirabilis was significantly slower for FLUME compared with latex Foley catheters, but not the silicone Foley. Stage 1 testing (10 patients) confirmed balloon inflation, drainage, retention and removal, with no serious adverse events caused by catheterisation; one balloon failed to inflate, one patient could not be catheterised. Of five patients at stage 2, one had the catheter for 28 days without complication, one experienced spontaneous balloon deflation (14th day) and three needed early removal (blood clot, bypassing, difficulty connecting the drainage bag). Bacterial profiles of two FLUME catheters retained at least 2 weeks matched the Foley catheters. Acquired catheter colouration (two FLUME, one Foley) was not associated with biochemical change in the material. Conclusion: FLUME catheter performed well in preclinical blockage and balloon tests. Tests in 15 patients confirmed basic function and additional training was not needed for staff familiar with Foley catheterisation. Clinical issues commonly seen with catheters included failed catheterisation, clot blockage and bypassing. In addition, an unintended balloon deflation and a failure of bag connection occurred. Plain language summary: This article describes a new catheter design which aims to improve patient comfort and safety, and maximise bladder drainage, by protecting the bladder from the exposed catheter tip and by locating the drainage holes better. Various tests were done to check the catheter retaining balloon was safe and how well the catheter did when exposed to bacteria that could block it. The catheter was also used in people for the first time, to check it could be put in safely and functioned as intended. The results showed the FLUME catheter did well in the balloon and blockage tests. Tests in 15 patients confirmed basic function and showed placement was easy for staff familiar with conventional catheters. There were some clinical issues typical of urinary catheters and some possible improvements were identified.

Can we increase the value of data from bladder diaries? International Consultation on Incontinence-Research Society 2023.

BACKGROUND: Bladder diaries represent a fundamental component in the assessment of patients presenting with lower urinary tract symptoms. Nevertheless, their importance often remains underappreciated and undervalued within clinical practice. This paper aims to conduct a comprehensive review of the existing literature concerning the utility of bladder diaries, underscore the criticality of their precision, elucidate the factors contributing to noncompliance with bladder diary completion, and investigate potential strategies for enhancing patient compliance. MATERIALS AND METHODS: A review of the English-language scientific literature available in the domains of Medline, Embase, Emcare, Midirs, and Cinahl was conducted. This was supplemented by discussion at the International Consultation on Incontinence Research Society Proposal session to define knowledge and identify gaps in knowledge surrounding the utility of bladder diaries. The existing evidence and outcome of the relevant discussion held in the meeting are presented. RESULTS: Bladder diaries (BD) serve to characterize the nature and severity of storage lower urinary tract symptoms (LUTS) and provide an objective record of an individual's urination patterns. They aid in the refinement and customization of treatment strategies based on the clinical responses documented in the diary, optimizing treatment outcomes. Notably, both BD and urodynamic studies (UDS) play complementary yet distinct roles in LUTS evaluation. BD offers a more comprehensive and accessible approach to assessing specific storage LUTS, particularly due to their affordability and widespread availability, especially in resource-limited settings. Nevertheless, the absence of a standardized BD format across global healthcare systems presents a significant challenge. Despite being recognized as reliable, noninvasive, validated, and cost-effective tools for evaluating patients with LUTS, the implementation and completion of BD have proven to be complex. The introduction of automated bladder diaries heralds an era of precise, real-time data collection, potentially enhancing the patient-clinician relationship. Completion of bladder diaries depends on an array of individual, social, and healthcare-specific factors. Compliance with bladder diary completion could be enhanced with clear instructions, patient education, regular follow-ups and positive re-enforcement. This study has identified four critical areas for future research: Addressing healthcare disparities between affluent and developing nations, enhancing the current functionality and effectiveness of bladder diaries, exploring the feasibility of incorporating bladder diaries into the treatment and education process and improving the quality and functionality of existing bladder diaries. CONCLUSION: Bladder diaries play a pivotal role in the evaluation and management of patients with LUTS, providing a holistic perspective. When their complete potential is harnessed, they have the capacity to revolutionize the paradigm of LUTS management, ushering in a patient-centered era of care.

Can we use machine learning to improve the interpretation and application of urodynamic data?: ICI-RS 2023.

INTRODUCTION: A "Think Tank" at the International Consultation on Incontinence-Research Society meeting held in Bristol, United Kingdom in June 2023 considered the progress and promise of machine learning (ML) applied to urodynamic data. METHODS: Examples of the use of ML applied to data from uroflowmetry, pressure flow studies and imaging were presented. The advantages and limitations of ML were considered. Recommendations made during the subsequent debate for research studies were recorded. RESULTS: ML analysis holds great promise for the kind of data generated in urodynamic studies. To date, ML techniques have not yet achieved sufficient accuracy for routine diagnostic application. Potential approaches that can improve the use of ML were agreed and research questions were proposed. CONCLUSIONS: ML is well suited to the analysis of urodynamic data, but results to date have not achieved clinical utility. It is considered likely that further research can improve the analysis of the large, multifactorial data sets generated by urodynamic clinics, and improve to some extent data pattern recognition that is currently subject to observer error and artefactual noise.

Research priorities for diagnostic instrumentation in urinary incontinence.

The International Consultation on Incontinence (ICI) captures current evidence on incontinence. The conference 'Incontinence: The Engineering Challenge XIII' in November 2021 heard an update on the most recent ICI summary on urodynamic testing. This paper summarises the ICI recommendations for future research in urodynamics, with a view to informing engineers of issues and challenges that could benefit from engineering solutions. Engineers are encouraged to contribute to the following areas of research, which will have a direct and positive effect on patients' quality of life and overall health: (a) Urine flow measurement: home- and app-based devices, machine learning analysis of flow shape, (b) Pressure measurement: normal values for and validation of new technologies, including air-filled, non-invasive and urethral pressure reflectometry, (c) Ultrasound imaging: bladder wall biomechanics, bladder shape analysis, (d) Assess normal and abnormal value ranges, and diagnostic performance and (e) Specific trials in understudied patient groups including those with symptoms resistant to treatment, children and the frail elderly.

ICS-SUFU standard: Theory, terms, and recommendations for pressure-flow studies performance, analysis, and reporting. Part 2: Analysis of PFS, reporting, and diagnosis.

AIMS: The Working Group (WG), initiated by the International Continence Society (ICS) Standardisation Steering Committee and supported by the Society of Urodynamics, Female Pelvic Medicine and Urogenital Reconstruction, has revised the ICS Standard for pressure-flow studies of 1997. METHODS: Based on the ICS standard for developing evidence-based standards, the WG developed this new ICS standard in the period from May 2020 to December 2022. A draft was posted on the ICS website in December 2022 to facilitate public discussion and the comments received have been incorporated into this final release. RESULTS: The WG has recommended analysis principles for the diagnosis of voiding dysfunction for adult men and women without relevant neurological abnormalities. New standard terms and parameters for objective and continuous grading of urethral resistance (UR), bladder outflow obstruction (BOO) and detrusor voiding contraction (DVC) are introduced in this part 2 of the standard. The WG has summarized the theory and recommendations for the practice of pressure-flow study (PFS) for patients in part 1. A pressure-flow plot is recommended for the diagnosis of every patient, in addition to time-based graphs. Voided percentage and post void residual volume should always be included in PFS analysis and diagnosis. Only parameters that represent the ratio or subtraction of pressure and synchronous flow are recommended to quantify UR and only parameters that combine pressure and flow in a product or sum are recommended to quantify DVC. The ICS BOO index and the ICS detrusor contraction index are introduced in this part 2 as the standard. The WG has suggested clinical PFS dysfunction classes for male and female patients. A pressure-flow scatter graph including every patient's pdet at maximum flow (pdetQmax ) with maximum flow rate (Qmax ) point should be included in all scientific reports considering voiding dysfunction. CONCLUSION: PFS is the gold standard used to objectively assess voiding function. Quantifying the dysfunction and grading of abnormalities are standardized for adult males and females.

ICS-SUFU standard: Theory, terms, and recommendations for pressure-flow studies performance, analysis, and reporting. Part 1: Background theory and practice.

AIMS: The working group (WG) initiated by the International Continence Society Standardization Steering Committee and supported by the Society of Urodynamics, Female Pelvic Medicine and Urogenital Reconstruction has revised the (1997) ICS Standard for pressure flow studies. METHODS: Based on the ICS standard for developing evidence-based standards, the WG developed this new ICS standard in the period from May 2020 to December 2022. A draft was posted on the ICS website in January 2023 to facilitate public discussion and the comments received have been incorporated into this final release. RESULTS: The WG summarizes the theory and recommends the practice and the terms used for the diagnosis of voiding dysfunction for adult female and male patients without relevant neurological abnormalities, in part 1 of this standard. The WG has also recommended standard principles and parameters for objective and continuous grading of urethral resistance and detrusor voiding contraction on the basis of pressure flow studies in part 2. The recommendations for practice in this part have also the aim to increase the understanding of the physiology as well as the psychology of voiding. The potential effects of the laboratory situation of the test on the voiding as well as the role of the urodynamicist in this regard are discussed. The WG has recommended to use for diagnosis only the voidings that are considered representative by the patient. CONCLUSION: A pressure flow study is the gold standard to assess voiding function and to quantify dysfunction. This part of the standard explains the clinical background, gives recommendations for the execution of a pressure flow study and lists relevant terms, parameters, and units of measurements.

Randomised Controlled Trials Assessing the Clinical Value of Urodynamic Studies: A Systematic Review and Meta-analysis.

Context: The role of urodynamic studies (UDSs) in the diagnosis of lower urinary tract symptoms (LUTS) is crucial. Although expert statements and guidelines underline their value for clinical decision-making in various clinical settings, the academic debate as to their impact on patient outcomes continues. Objective: To summarise the evidence from all randomised controlled trials assessing the clinical usefulness of UDS in the management of LUTS. Evidence acquisition: For this systematic review, searches were performed without language restrictions in three electronic databases until November 18, 2020. The inclusion criteria were randomised controlled study design and allocation to receive UDS or not prior to any clinical management. Quality assessment was performed by two reviewers independently, using the Cochrane Collaboration's tool for assessing the risk of bias. A random-effect meta-analysis was performed on the uniformly reported outcome parameters. Evidence synthesis: Eight trials were included, and all but two focused on women with pure or predominant stress urinary incontinence (SUI). A meta-analysis of six studies including 942 female patients was possible for treatment success, as defined by the authors (relative risk 1.00, 95% confidence interval: 0.93-1.07), indicating no difference in efficacy when managing women with UDS. Conclusions: Although UDSs are not replaceable in diagnostics, since there is no other equivalent method to find out exactly what the lower urinary tract problem is, there are little data supporting its impact on outcomes. Randomised controlled trials have focussed on a small group of women with uncomplicated SUI and showed no added value, but these findings cannot be extrapolated to the overall patient population with LUTS, warranting further well-designed trials. Patient summary: Despite urodynamics being the gold standard to assess lower urinary tract symptoms (LUTS), as it is the only method that can specify lower urinary tract dysfunction, more studies assessing the clinical usefulness of urodynamic studies (UDSs) in the management of LUTS are needed. UDS investigation is not increasing the probability of success in the treatment of stress urinary incontinence.

Bristol UTraQ: A proposed system for scoring the technical quality of urodynamic traces.

AIM: To develop and test a scoring system for the technical quality of a urodynamic trace METHODS: Rasch analysis was used to select the most discriminating questions relating to good urodynamic practices. The questions were taken from International Continence Society standard documents and tested on 60 traces of varying quality and from different sources. RESULTS: Twenty-five questions were selected by this process. These were tested with 10 traces by seven scorers, and with 60 traces by a single scorer. A pass quality score of 75% resulted in good discrimination between good and poor traces. Further editing and clarification resulted in a final score sheet of 23 Yes/No questions. CONCLUSION: A proposed scoring system, "Bristol UTraQ," for the technical quality of urodynamic traces has been developed and tested. We suggest a score above 75% indicates acceptable trace technical quality. High technical quality is the essential first step in ensuring that urodynamic studies can answer the urodynamic questions for every patient. Plans for further validation are outlined.

Assessment of quality in urodynamics: Cough versus valsalva.

INTRODUCTION: To ensure quality, the International Continence Society recommends asking the patient to cough every minute or 50 ml of infused volume. However, on occasions, it was noticed that if cough transmission was poor, Valsalva maneuvers could show pressure transmission was satisfactory. Hence, a study was designed to compare the two methods. METHODS: Cough and Valsalva maneuver pressures were compared in 40 patients, 20 consecutive men and 20 consecutive women, undergoing urodynamics at three time points: baseline (20 ml filling), prevoid and postvoid. RESULTS: At baseline, the percentage difference between pabd and pves was significantly lower for Valsalva maneuvres compared with coughs for all patients (median 5.1% vs. 10.2%). This association was consistent in male patients, but not for female. At prevoid, this was reversed with coughs providing more consistent pressure spikes than Valsalva maneuvers (median 7.0% vs. 24.1%), for all patients. Postvoid, no difference was noted in either men or women. CONCLUSIONS: Quality control during urodynamics is important to ensure diagnostic accuracy. This is the first study to compare two methods of quality control, coughs, and Valsalva maneuvers. Coughs are a useful indicator of pressure transmission quality at all time points throughout urodynamic studies. However, at low volumes, Valsalva maneuvers give a better indication of quality, with lower variability, whereas at cystometric capacity coughs performed better. Therefore, if poor pressure transmission occurs with cough during urodynamics, particularly at low volumes, it is recommended that a Valsalva maneuver is used to further assess whether pressure transmission and thus urodynamic quality is satisfactory.

Development of a more clinically relevant bladder and urethral model for catheter testing.

This paper sets out the rationale and design for a more physiologically representative bladder/urethral model than the current rigid funnel industry standard. We suggest this flexible model can better serve as a basis for evaluating new catheters. We investigated the parameters and the validation tests required to construct and test with more flexible materials. The protocol includes static and impact force tests, while measuring internal retention balloon pressure. We have designed a flexible elastomer bladder floor and urethral model and tested it with a Foley balloon catheter. The tests showed that the model could hold the catheter with static loads up to 0.7 kg, but that the catheter was pulled out by impact forces from dropped weights. The Foley catheter design and its associated standards make no provision to mitigate urethral injury in the surprisingly common event of removal with a filled balloon. Our design is a more realistic model for testing retention and extraction characteristics of a urethral catheter. Validation tests have confirmed the feasibility of measuring urethral dilation and balloon pressure, both under traction and during progressive deflation. We suggest this model improves upon the current standard tests and will enable the design of safer catheters.

Compliance to Individualized Recommendations Based on an Evidence-Based Algorithm for Behavioral Management of Lower Urinary Tract Symptoms.

PURPOSE: The aim of this study was to evaluate patient compliance to individualized recommendations for self-management of fluid intake, bladder irritants, and timing of fluid consumption. DESIGN: Single-group, before-after pilot study. SUBJECTS AND SETTING: The sample comprised 22 patients (17 male and 5 females, mean age 62 years, age range 27-84 years). The study setting was the uroflow clinic at Southmead Hospital, Bristol, UK, a tertiary level referral hospital for complex evaluation and treatment of urological patients. METHODS: Patients were given a bladder diary to complete after 2 weeks, which was compared with the bladder diary they had originally brought to clinic, to see whether the advice was followed. The bladder diary used required the patient to document the times and volumes of urination over a period of 3 days, magnitude of urinary urgency felt at the time, along with fluid intake timing, amount, and type of beverage. The study was not designed to measure changes in symptoms, but observed changes recorded in the bladder diaries are reported. RESULTS: All 6 of the 22 participants who were advised to increase the volume of fluid intake complied, with an increased average intake of a mean of 520 mL (range 100-1450 mL). Similarly, one participant advised to reduce fluid intake decreased their fluid intake by 1800 mL per day. Thirteen out of 16 patients (81%) who were advised to remove caffeine, alcohol, or artificial sweeteners from their diet complied, indicated by no bladder irritant being recorded on their bladder diary. Nine out of 12 patients (75%) advised to reduce fluid intake in the evenings complied, decreased fluid intake after 6 PM by an average of 240 mL (range 100-550 mL less). CONCLUSIONS: A majority of participants given fluid intake advice that is specific to their symptoms and lifestyle complied with recommendations. Simple guidance could usefully be given to patients before they are referred to specialist urological care or undergo urodynamic testing.

Good urodynamic practice adaptations during the COVID-19 pandemic.

Urodynamics testing forms the cornerstone of investigations when it comes to lower urinary tract dysfunction. It has to be done to the highest standards by following the International Continence Society Good Urodynamics Practice protocols. However, with the COVID-19 pandemic, certain adaptations to the urodynamics procedure need to be considered especially when it comes to quality control. This article aims to define these adaptations to help urodynamicists in their daily practice.

Quality control of uroflowmetry and urodynamic data from two large multicenter studies of male lower urinary tract symptoms.

AIM: The International Continence Society (ICS) has standardized quality control and interpretation of uroflowmetry and urodynamics. We evaluated traces from two large studies of male lower urinary tract symptoms (UPSTREAM and UNBLOCS) against ICS standards of urodynamic equipment and practice. METHODS: Ten percent of uroflowmetry and urodynamics traces were selected at random from hospital sites. A data capture template was designed from the ICS Fundamentals of Urodynamic Practice checklist. Two pretrained blinded assessors extracted the data, with a third assessor to arbitrate. Departmental records of calibration checks and equipment maintenance were scrutinized. RESULTS: Seven out of twenty-five (28%) departments reported no calibration checks. Four sites (16%) could not provide annual service records. In 32 out of 296 (10.8%) uroflowmetry traces, findings were affected by artifact. One hundred ten urodynamic study traces were reviewed; in 11 records (10%), key pressure traces were incompletely displayed. In 30 (27.2%), reference zero was not set to atmospheric pressure. Resting pressures were outside the expected range for 36 (32.7%). Pressure drift was seen in 18 traces (16.4%). At pressure-flow study commencement, permission to void was omitted in 15 (13.6%). Cough testing after voiding was done in 71.2%, but the resulting cough spikes were significantly different in 16.5%. Erroneous diagnosis of bladder outlet obstruction (BOO) was identified in six cases (5.5%). CONCLUSIONS: Erroneous diagnosis of BOO is a serious error of interpretation, as it could lead to unnecessary surgery. Other errors of standardization, testing, and interpretation were identified with lower risk of adverse implications. Inconsistent documentation of service records mean equipment accuracy is uncertain.

What developments are needed to achieve less-invasive urodynamics? ICI-RS 2019.

AIMS: To assess the state of technologies for urodynamics that are less invasive than standard cystometry and pressure-flow studies and to suggest areas needing research to improve this. METHODS: A summary of a Think Tank debate held at the 2019 meeting of the International Consultation on Incontinence Research Society is provided, with subsequent analysis by the authors. Less-invasive techniques were summarized, classified by method, and possible developments considered. Discussions and recommendations were summarized by the co-chairs and edited into the form of this paper by all authors. RESULTS: There is a full spectrum of technologies available for less-invasive assessment, ranging from simple uroflowmetry through imaging techniques to emerging complex technologies. Less-invasive diagnostics will not necessarily need to replace diagnosis by, or even provide the same level of diagnostic accuracy as, invasive urodynamics. Rather than aiming for a technique that is merely less invasive, the priority is to develop methods that are either as accurate as current invasive methods, or spare patients from the necessity of invasive methods by improving early triaging. CONCLUSIONS: Technologies offering less-invasive urodynamic measurement of specific elements of function can be potentially beneficial. Less-invasive techniques may sometimes be useful as an adjunct to invasive urodynamics. The potential for current less-invasive tests to completely replace invasive urodynamic testing is considered, however, to be low. Less-invasive techniques must, therefore, be tested as screening/triaging tools, with the aim to spare some patients from invasive urodynamics early in the treatment pathway.

Can multicentre urodynamic studies provide high quality evidence for the clinical effectiveness of urodynamics? ICI-RS 2019.

AIMS: Lower urinary tract (LUT) function can be investigated by urodynamic studies (UDS) to establish underlying functional abnormalities in the LUT. A multicentre registry could present an opportunity to improve the scientific evidence base for UDS. During the International Consultation on Incontinence Research Society (ICI-RS) meeting in Bristol, United Kingdom 2019, an expert panel discussed the potential of a multicentre urodynamic registry to improve the quality of urodynamic output. METHODS: the potential importance of a multicentre urodynamic registry, parameter inclusion, quality control, and pitfalls during a registry roll-out were reviewed and discussed. RESULTS AND CONCLUSIONS: The clinical utility, evaluation, and effectiveness of UDS remain poorly defined due to a lack of high quality evidence and large study populations. Therefore, the ICI-RS proposes formation of a urodynamic panel for future roll-out of a registry. The inclusion of basic parameters was discussed and the essential parameters were defined as well as the potential pitfalls of a registry roll-out. The discussion and recommendations in this paper form the base for future urodynamic registry development.

Urodynamics Useless in Female Stress Urinary Incontinence? Time for Some Sense-A European Expert Consensus.

BACKGROUND: Routine use of urodynamics (UDS) for the assessment of female stress urinary incontinence (SUI) appears to be in decline across Europe. The reasons for this trend appear multifactorial, but the implications are of significant concern. OBJECTIVES: To achieve an expert consensus viewpoint on the value of UDS in female SUI and current barriers to its use. METHODOLOGY: A multidisciplinary group of UDS experts from six European countries was convened, and a modified version of the Delphi method was utilised to reach a consensus viewpoint structured around five key questions. RESULTS: Consensus was achieved on all five questions. The group was unanimous that the decline in routine use of UDS is unjustified and misguided, driven by restrictions in funding and accelerated by the publication-and subsequent influence-of two trials that had major limitations. LIMITATIONS: The authors comprised a selected group of UDS experts and the analysis is not a formal systematic review. CONCLUSIONS: Extensive experience and observational studies have demonstrated the value of UDS for the assessment of female SUI and the dangers of empiric management. This evidence base should not be eclipsed by the findings of two randomised controlled trials that had numerous shortcomings. PATIENT SUMMARY: A group of experts were worried that, even though the cause of incontinence varies, doctors seem to be skipping a diagnostic test called urodynamics (UDS) in some patients and just providing treatment-even surgery-without knowing exactly what is wrong. These experts analysed the situation in detail and reached agreement that UDS testing should not be skipped.