Andrew Gammie

International continence society guidelines on urodynamic equipment performance

These guidelines provide benchmarks for the performance of urodynamic equipment, and have been developed by the International Continence Society to assist purchasing decisions, design requirements, and performance checks. The guidelines suggest ranges of specification for uroflowmetry, volume, pressure, and EMG measurement, along with recommendations for user interfaces and performance tests. Factors affecting measurement relating to the different technologies used are also described. Summary tables of essential and desirable features are included for ease of reference. It is emphasized that these guidelines can only contribute to good urodynamics if equipment is used properly, in accordance with good practice. Neurourol. Urodynam. 33:370–379, 2014.

Signs and Symptoms of Detrusor Underactivity: An Analysis of Clinical Presentation and Urodynamic Tests From a Large Group of Patients Undergoing Pressure Flow Studies

BACKGROUND The clinical diagnosis of detrusor underactivity (DU) is hampered by the need for invasive pressure flow studies (PFS) in combination with a lack of knowledge of the associated signs and symptoms. This has contributed to a lack of awareness of DU and underactive bladder, and to the assumption that symptoms are always due to bladder outlet obstruction (BOO). OBJECTIVE To investigate the signs and symptoms recorded in a large urodynamic database of patients who met the diagnoses of DU, BOO, and normal, to identify the clinical features associated with DU. DESIGN, SETTING, AND PARTICIPANTS From the database of 28282 adult PFS records, 1788 patients were classified into: (1) those with DU without BOO; (2) those with BOO without DU; and (3) those with normal PFS. RESULTS Patients with DU reported a statistically significantly higher occurrence of decreased and/or interrupted urinary stream, hesitancy, feeling of incomplete bladder emptying, palpable bladder, and absent and/or decreased sensation compared with patients with normal PFS. Other differences were found between men with DU and BOO, and between women with DU and normal PFS. CONCLUSIONS There are signs and symptoms that can distinguish DU patients from patients with normal PFS and further distinguish between DU and BOO, which is traditionally invasively diagnosed. This is a first step to better understand the clinical presentation of DU patients, is consistent with the recent underactive bladder working definition, and justifies further exploration of the signs and symptoms of DU. PATIENT SUMMARY The clinical diagnosis of detrusor underactivity is hampered by the need for invasive urodynamics in combination with a lack of knowledge of the associated signs and symptoms. This study has shown that there are signs and symptoms that can distinguish men and women patients with DU from patients with either normal urodynamic studies or with BOO.

Bladder Compliance What Does it Represent: Can We Measure it, and is it Clinically Relevant?

To report the conclusion of the Think Thank 8 on Compliance Discussions during the second ICI‐RS meeting in 2010.

Urodynamic features and artefacts

The aims of this study are to compile a list of common features and artefacts found in urodynamics, to produce definitions of these features, and describe any necessary remedial action. An image and word description for each event has been included as well as statistics providing information on the prevalence and frequency of each event.

The Validation of a Functional, Isolated Pig Bladder Model for Physiological Experimentation

Characterizing the integrative physiology of the bladder requires whole organ preparations. The purpose of this study was to validate an isolated large animal (pig) bladder preparation, through arterial and intravesical drug administration, intravesical pressure recording, and filming of surface micromotions. Female pig bladders were obtained from the local abattoir and arterially perfused in vitro. Arterial and intravesical pressures were recorded at varying volumes. Bladder viability was assessed histologically and by monitoring inflow and outflow pH. Arterial drug administration employed boluses introduced into the perfusate. Intravesical administration involved slow instillation and a prolonged dwell-time. Surface micromotions were recorded by filming the separation of surface markers concurrently with intravesical pressure measurement. Adequate perfusion to all bladder layers was achieved for up to 8 h; there was no structural deterioration nor alteration in inflow and effluent perfusate pH. Arterial drug administration (carbachol and potassium chloride) showed consistent dose-dependent responses. Localized movements (micromotions) occurred over the bladder surface, with variable correlation with fluctuations of intravesical pressure. The isolated pig bladder is a valid approach to study integrative bladder physiology. It remains viable when perfused in vitro, responds to different routes of drug administration and provides a model to correlate movements of the bladder wall directly to variation of intravesical pressure.

Evaluation of obstructed voiding in the female: how close are we to a definition?

Purpose of review The difficulties of defining and evaluating bladder outlet obstruction (BOO) in the female patient have been described for several years. This review aims to examine recent literature to summarize progress in the area. Recent findings Within the last 2 years, functional causes of female BOO have been summarized, new nomograms proposed, several case reports of different causes of BOO have been published and work on surgical outcomes and possible diagnostics reported. Summary Women complain of voiding dysfunction because of different reasons. For clinical decision-making, and to evaluate different surgical procedures, finding a way of detecting and quantifying infravesical obstruction is immensely helpful. This review aims to clarify questions concerning definitions of BOO in women and provide an update on recent advances.

Simultaneous in vivo comparison of water-filled and air-filled pressure measurement catheters: Implications for good urodynamic practice

This study aimed to evaluate whether the pressure readings obtained from air‐filled catheters (AFCs) are the same as the readings from simultaneously inserted water‐filled catheters (WFCs). It also aimed to make any possible recommendations for the use of AFCs to conform to International Continence Society (ICS) Good Urodynamic Practices (GUP).

Recommendations for future development of contractility and obstruction nomograms for women. ICI-RS 2014.

At present, existing bladder outlet obstruction (BOO) nomograms for women are still not universally accepted. Moreover, only limited information is available regarding bladder contractility in women. The aim is to present the discussions and recommendations from the think tank session “Can we construct and validate contractility and obstruction nomograms for women?” held at the 2014 International Consultation on Incontinence‐Research Society (ICI‐RS) meeting in Bristol, UK.

Estimation of bladder contractility from intravesical pressure-volume measurements

To describe parameters from urodynamic pressure recordings that describe urinary bladder contractility through the use of principles of muscle mechanics.

Air filled, including "air-charged," catheters in urodynamic studies: Does the evidence justify their use?

Air filled catheters (AFCs) have been actively marketed for the past few years and in some geographic areas are widely used. However, as the scientific basis for introduction of this technology for pressure measurement in urodynamics was not clear, a study group examined the evidence.