Assessment of quality in urodynamics: Cough versus valsalva

Evaluation of the effectiveness of four alternative approaches for the classical cough test during a urodynamic study in the context of the COVID-19 global pandemic

BACKGROUD

To evaluate four different alternatives to the classical cough test during a urodynamic study in the context of the COVID-19 pandemic.

METHODS

Patients who needed to undergo a urodynamic study (UDS) at the West China Hospital of Sichuan University between April 2021 and May 2021 were randomly selected according to the inclusion and exclusion criteria. During the UDS process, we used four alternative methods to the "cough test": 1) quickly pressing the bladder area, 2) performing the Valsalva maneuver, 3) performing the Kegel maneuver, and 4) letting the patient close their mouth while performing the cough test. The "cough" waveform amplitudes and characteristics of the graphics were obtained and compared with the classical cough test.

RESULTS

A total of 120 patients (89 men, 31 women) were included in the study. There was no significant difference between the cough waveform amplitude induced by the Valsalva maneuver compared with the classical cough test (P = 0.182); there was no significant difference between the cough waveform amplitude induced by the cough test with the mouth closed and the classical cough test (P = 0.342); there was no significant difference between pressing quickly on the bladder area and the classical method (P = 0.076); and there was a significant difference between the data obtained by the Kegel maneuver and the classical method (P < 0.05). The average "cough" amplitudes obtained were 73.14 ± 22.48 cm H2O, 66.17 ± 17.12 cm H2O, 82.93 ± 18.95 cm H2O, 26.50 ± 8.68 cm H2O, and 68.90 ± 20.32 cm H2O by the classical cough test, by quickly pressing the bladder area, by the Valsalva maneuver, by the Kegel maneuver, and by coughing with a closed mouth, respectively.

CONCLUSION

Quickly pressing the bladder area, performing the Valsalva maneuver, and letting the patient close their mouth while performing the cough test can all provide effective cough waveforms and amplitudes.

TRIAL REGISTRATION

No. 2021-183.

Pressure-Volume Loop Analysis of Voiding Workload: An Application in Trans-Vaginal Mesh-Repaired Pelvic Organ Prolapse Patients

Although trans-vaginal mesh (TVM) offers a successful anatomical reconstruction and can subjectively relieve symptoms/signs in pelvic organ prolapse (POP) patients, its objective benefits to the voiding function of the bladder have not been well established. In this study, we investigated the therapeutic advantage of TVM on bladder function by focusing on the thermodynamic workload of voiding. The histories of 31 POP patients who underwent TVM repair were retrospectively reviewed. Cystometry and pressure volume analysis (PVA) of the patients performed before and after the operation were analyzed. TVM postoperatively decreased the mean voiding resistance (mRv, p < 0.05, N = 31), reduced the mean and peak voiding pressure (mPv, p < 0.05 and pPv, p < 0.01, both N = 31), and elevated the mean flow rate (mFv, p < 0.05, N = 31) of voiding. While displaying an insignificant effect on the voided volume (Vv, p < 0.05, N = 31), TVM significantly shortened the voiding time (Tv, p < 0.05, N = 31). TVM postoperatively decreased the loop-enclosed area (Apv, p < 0.05, N = 31) in the PVA, indicating that TVM lessened the workload of voiding. Moreover, in 21 patients who displayed postvoiding urine retention before the operation, TVM decreased the residual volume (Vr, p < 0.01, N = 21). Collectively, our results reveal that TVM postoperatively lessened the workload of bladder voiding by diminishing voiding resistance, which reduced the pressure gradient required for driving urine flow.

[Is pressure transmission quality during cystometry dependent on the type of effort?]

INTRODUCTION

The International Continence Society (ICS) recommends a control of the good pressure transmission by a coughing effort during cystometry. While poor transmission is sometimes observed in routine practice, other maneuvers can also be proposed. The main objective of this study was to determine if there is a better maneuver to evaluate the pressure transmission ratio between the abdominal cavity and the bladder.

METHODS

We performed a prospective, consecutive, single-center study in a tertiary neuro-urology department in 31 subjects. During a cystometry, each patient was asked to perform at 0ml and 100ml of bladder filling, a cough effort, an abdominal push and a Valsalva maneuver controlled by a manometer. The value of the bladder pressure to abdominal pressure ratio was collected manually. The average variations were compared between each maneuver for the same volume of replenishment and between the 2 volumes of replenishment studied.

RESULTS

At 0ml of filling, the difference in pressure variation between the Pves and the Pabd is significantly higher during the cough maneuver compared to the Valsalva (P=0.015), which is not found at 100ml of filling.

CONCLUSION

During bladder filling, the pressure transmission ratios during the 3 maneuvers are equivalent. Coughing or abdominal thrusting, which are easier to perform than the Valsalva maneuver, should be recommended to check the quality of the recording during cystomanometry.

LEVEL OF EVIDENCE: 4

Modification of bladder thermodynamics in stress urinary incontinence patients submitted to trans-obturator tape: A retrospective study based on urodynamic assessment

Importance: It needs to be clarified whether trans-obturator tape (TOT)-enhanced urethral resistance could impact the voiding function.

Objective: Although TOT has been well-recognized for enhancing urethral resistance to restore continence in stress urinary incontinence (SUI) patients, whether the bladder’s voiding functions adapt to the TOT-enhanced resistance has not been adequately investigated. This study thereby aimed to investigate whether TOT impacts the bladder’s thermodynamic efficacy during the voiding phase.

Design: A retrospective analysis of urodynamics performed before and after TOT was assessed.

Setting: A tertiary referral hospital in Taiwan.

Participants: A total of 26 female SUI patients who underwent urodynamic investigations before and after TOT.

Main outcomes and measures: The area enclosed by the pressure-volume loop (Apv), which represents the work performed by the bladder during voiding, in a pressure-volume analysis established by plotting the detrusor pressure versus intra-vesical volume was retrospectively analyzed. Paired Student’s t-tests were employed to assess the difference in values before and after the operation. Significance in difference was set at p &lt; 0.05.

Results: TOT increased Apv in 20 of 26 (77%) patients and significantly increased the mean Apv compared to the preoperative control (2.17 ± 0.18 and 1.51 ± 0.13 × 103 cmH2O-ml, respectively p &lt; 0.01). TOT also increased the mean urethral resistance (1.03 ± 0.30 vs. 0.29 ± 0.05 cmH2O-sec/ml, p &lt; 0.01) and mean voiding pressure (25.87 ± 1.72 and 19.30 ± 1.98 cmH2O p &lt; 0.01) but did not affect the voided volume and voiding time. Moreover, the TOT-induced Apv increment showed a moderate correlation with the changes in urethral resistance and voiding pressure (both r &gt; 0.5) but no correlation with changes in voided volume or voiding time. It is remarkable that the TOT-induced urethral resistance increment showed a strong correlation with changes in voiding pressure (r &gt; 0.7).

Conclusion and Relevance: The bladder enhances thermodynamic efficacy by adapting the voiding mechanism to increased urethral resistance caused by TOT. Further studies with higher case series and longer follow-ups should assess whether this effect could be maintained over time or expire in a functional detrusor decompensation, to define diagnostic criteria that allow therapeutic interventions aimed at its prevention during the follow-up.

Clinical Trial Registration: (clinicaltrials.gov), identifier (NCT05255289)