Initially, water-filled catheters were the only urodynamics (UDS) catheter technology available. With the demand for different and easier ways to assess lower urinary tract (LUT) dysfunction, multiple catheter technologies have been developed such as air-charged and electronic catheters. Currently, most electronic catheters on the market are reusable which can increase the risk of infection. The e•Sense® electronic catheters are single-use disposable UDS catheters currently available on the market, to which changes were made to improve the catheter design.
The aim of this study was to assess whether the updated version of the device is safe and effective for urodynamic use in adult patients medically indicated for UDS. As an exploratory aim, subjective patient feedback regarding discomfort and pain experienced, and clinical user feedback was collected.

The study was planned and executed as a pre-market study of the updated 7Fr e•Sense® Urodynamics catheters models: Single Sensor Bladder, Dual Sensor Urethral, and Single Sensor Abdominal. The study was approved by the local ethics committee and informed consent obtained from all patients. Inclusion criteria were men and women 21 years and older medically indicated for UDS. Patients unable to give informed consent, as well as patients with an active bladder infection or subjects with recent (less than 2 weeks) pelvic floor surgery were excluded. 
The UDS procedures were done per our routine continence clinic according to the ICS Good Urodynamic Practice (GUP) standards.(1) The catheters were zeroed to atmosphere and then inserted into the patient. Following the procedure, patients capable of providing feedback responded to questions regarding their level of discomfort and pain experienced during the UDS procedure using a Numerical Pain Rating Scale (NPRS). The scale ranged from 0 (no pain) to 10 (worst pain) and was presented to the patient immediately after their UDS test. A follow-up telephone interview 3-5 days after the UDS test was done to collect post-test adverse event information.
The primary safety and effectiveness aim was a binary (yes/no) investigator response for each patient recruited to receive a UDS study using the new device for bladder, abdominal and optionally urethral pressure measurement, to determine whether the catheter was clinically adequate (success) or inadequate (failure). 
All clinical users were asked to complete a subjective questionnaire at the end of each clinic day for their impression of device usability compared with their experience using water-filled and/or air-charged catheters. The users were asked about the overall ease of catheter use, overall stability and overall quality of the tracing, quality of channel subtraction during provocative maneuvers, and overall usability performance. These answers were used to examine the exploratory aim using subjective, ordinal scales [e.g. 1 (worse than), 2 (slightly worse), 3 (no difference) 4 (slightly better), 5 (much better)].  
For the primary aim statistical analysis, 30 subjects would provide 88% power to rule out a success rate ≤ 75% when the true success rate is assumed to be 96%, based on a 1-sided test with type I error rate of 2.5%. p<0.025 was used to indicate a statistically significant result. All subjective results are presented below as mean (min-max).

Thirty-one patients were recruited, and 30 patients completed the study to support the primary composite safety and effectiveness analysis. The study population comprised 8 men (25.8%) and 23 women (74.2%), mean age was 54 years old (31-83). Three of the women underwent a urethral pressure profile (UPP) using the dual sensor urethral catheter. Only 7/31 (29%) had undergone a previous UDS test, and 16/31 (51.6%) were neurogenic cases. 
The primary analysis population had a successful outcome in 29/30 (96.7%) patients (95% CI, 82.8 to 99.9%, p=0.002). The sensitivity analysis population had a successful outcome in 29/31 (93.5%) patients (95% CI, 78.6 to 99.2%, p=0.0084). In one case, catheterization failed due to anatomical factors and therefore this patient was included in the sensitivity (secondary) analysis. In another case, a device deficiency resulted in one patient not able to complete the UDS, however, they were still included in the primary analysis. These results were statistically significant with a 1-sided p<0.025. 
All patients reported their pain and discomfort experienced indicating low NPRS bother. The mean response for bladder catheter insertion was 1.2 (0-5), during the test (bladder filling) was 0.7 (0-6) and during catheter removal was also 0.5 (0-3). The abdominal catheter mean response was 0.6 (0-3) during insertion, and 0.3 (0-2) during removal. During catheter insertion, 87.1% and 90.3% of patients reported NPRS of 2 or lower for the bladder and abdominal insertion, respectively. Lastly, the mean response for the three patients who underwent UPP was 0.7 (0-2). All 31 patients indicated they would be willing to do the test again if medically necessary. 
Three experienced UDS nurses provided usability feedback where the overall ease of use mean rating was 3.0 (3-4), overall stability of the tracing was 3.7 (3-4), and overall quality of the tracing was 3.6 (3-4). The quality of channel subtraction during provocative maneuvers was 3.7 (3-4), and overall usability performance was 3.8 (2-4). 
There were 11 adverse events affecting nine patients, and no serious events were recorded. All adverse events were classified as mild. No follow-up treatment was required, and only one event of 'mild macrohematuria' lasted two days (all others resolved within one day). Seven patients reported mild discomfort in the urethra, and three patients reported mild macrohematuria. The only unexpected adverse event was diarrhea lasting for less than one day, most likely not related to the device tested.

The results of this study confirm that the updated e•Sense® electronic catheter is safe and effective for urodynamic use. The two failures that occurred were one failed catheterization attempt due to patient anatomy, and one technical catheter problem, which were isolated events and did not impact the overall safety and effectiveness of the catheter. 
The test was well tolerated by all patients as indicated by the low NPRS results. Patient satisfaction was demonstrated by willingness of all patients to repeat the test if it were necessary. 
The overall usability feedback was rated as either 3 (equal performance) or greater in all cases, except for one patient where a rating of 2 was given (“bad”) as the urethral catheter slipped out during stress UPP testing.

The new e•Sense® electronic urodynamics catheters were considered safe and effective under the intended use, with low patient bother. The usability feedback gathered indicate the catheters were considered at least as good or better than the water-filled and air-charged catheters from a clinical user perspective.

Rosier PFWM, Schaefer W, Lose G, Goldman HB, Guralnick M, Eustice S, et al. International Continence Society Good Urodynamic Practices and Terms 2016: Urodynamics, uroflowmetry, cystometry, and pressure-flow study. Neurourology and Urodynamics. 2017 Jun;36(5):1243-1260. https://doi.org/10.1002/nau.23124