Introduction

Urodynamics (UDS) are the current gold standard investigations to explain pathology in lower urinary tract dysfunction. The role of UDS is to answer a urodynamic question [1] based on reproducing the patient’s symptoms (http://wiki.ics.org/file/view/Good_Urodynamic_Practices-_Uroflowmetry,_Filling_Cystometry,_and_Pressure-Flow_Studies.pdf). Despite the introduction of several standardization documents on terminology [2] and methodology for performing UDS and the standard of equipment required [3], there remains no standardization on how to report and therefore how to interpret UDS findings. The lack of guidance in this specific area may undermine the value of this extremely important tool in the patient evaluation. The aim of this document is to propose a standardized proforma and checklist for the reporting of urodynamic studies (Fig. 1, supplemental material); the main text discusses the rationale for the proforma.

Fig. 1
figure 1figure 1

Proposed standardized proforma and checklist for the reporting of urodynamic studies

Full size image

Reporting terminology

The reporting terminology is as follows:

Reporting [4] refers to “giving an account or summary given or an opinion formally expressed after investigation or consideration.”

Comprehensive refers to “complete, including all or nearly all elements, aspects etc.”

Urogynecological refers to “clinical problems related to lower urinary tract and pelvic floor dysfunction.”

Assessment (of a patient) refers to “the evaluation of the patient using selected skills of history-taking; physical examination, laboratory, imaging and social evaluation, to achieve a specific goal.”

Urodynamics refers to “the study of the storage of urine within, and the flow or urine through and from, the urinary tract.”

Methods

This document underwent four rounds of review by the working group and external review by Andrew Gammie; between each round, the document was re-circulated for comment and the comments collated and then reviewed for adoption or rejection based on consensus prior to the document going for further external review. The comments of the external review were then collated and again circulated for consideration prior to adoption based on consensus and the paper put out to review by an IUGA committee public consultation prior to being submitted for publication.

Results

This article sets out the rationale for a standardized proforma for reporting female urodynamics. The document is set out in in eight sections:

  1. 1.

    The urodynamic question.

  2. 2.

    Patient symptoms/history/examination.

  3. 3.

    Bladder diary.

  4. 4.

    Equipment set-up and quality assurance.

  5. 5.

    Reporting of urodynamic observations.

  6. 6.

    Interpretation/conclusion.

  7. 7.

    Did the test change management?

  8. 8.

    Research/governance

The urodynamic question: Reporting of indications for urodynamics

It is crucial before requesting any UDS study to clearly establish a clinically relevant question to be answered. For that reason, the recommendation is to specify an exact clinical question to be answered from a predefined checklist. This list includes an open-ended “other” option.

Example: Asking the right question is important; one may observe urodynamic stress incontinence (USI), but if the question is about voiding difficulties and the patient does not complain of stress urinary incontinence then the observation of leakage is not clinically relevant and treatment of USI would be inappropriate and possibly detrimental to the patient’s symptoms.

Patient symptoms: History/examination

Correlating patient symptoms with the urodynamic diagnosis is crucial, and the urodynamist needs to be certain that the test is appropriate. The key to this is that the test may have been ordered by one health care professional (HCP) who may or may not be experienced in pelvic floor medicine. Also, the report may go back to a different HCP who may not check the patient’s symptoms and rely solely on the urodynamic report; as such, it is crucial the report contains exactly why the test is being done and that the patient symptomatology fits with the question being asked.

Bladder diary

Bladder diaries are key components of lower urinary tract (LUT) symptom assessment. Ideally a minimum 3-day diary should be completed. This should contain voided volumes and symptoms including urgency and incontinence episodes. Useful additional information may include fluid intake and type, waking time and bedtime. The importance of the latter is that they enable assessment of nocturnal symptoms and true nocturnal polyuria.

Equipment set-up and quality assurance

The equipment must be correctly assembled, and appropriate calibration and maintenance must be performed according to manufacturer recommendation. Valid zeroing should be performed and documented (to atmosphere with fluid-filled catheters). The quality of the subtraction of the rectal pressure from bladder pressure on the detrusor should be noted and the value reported as a marker of quality and reliability of the test.

Calibration and maintenance should be according to the manufacturer’s recommendation. Details of technique should be logged in a separate ledger as part of the local quality control as a record for medical physics services.

The UDS technique details are extremely relevant for interpretation and therefore must be included in the reporting system. The recommendation is to include the following variables in the report:

  • Patient position

  • Any abnormalities on physical examination that could affect quality of UDS (e.g., urethral abnormalities, pelvic organ prolapse, rectal prolapse, vesico-vaginal fistula and anything which might affect rectal/intra-abdominal pressure, e.g., severe constipation). These may be included in the UDS question if appropriate.

  • Fluid type.

  • Fluid temperature

  • Filling rate.

  • Recording of catheterization technique, catheter type and size.

  • Recording of provocative maneuvers (including volume instilled and filling rate).

  • Residual measurement technique.

  • Whether the bladder was empty at the start of filling. If not, estimation of residual volume.

Reporting of urodynamic observations

  1. 1.

    Non-invasive flow studies (free flow rate) and free flow studies are essential in the evaluation of voiding patterns and characteristics of the emptying phase. These studies are much more physiological than multichannel UDS for these purposes. The recommendation is to report the total volume void, patterns of void using a preset list of patterns following the IUGA/ICS recommendation, maximum flow, voiding pattern and time and post-void residual (PVR).

  2. 2.

    Invasive UDS studies, negative dipstick or MSU beforehand should be recorded.

    1. a.

      At the start of the study, the PVR should be recorded, and documentation of whether there was an empty bladder at the start of the test should also be recorded. In addition, the method used to assess the PVR should be recorded (e.g., catheter or bladder scan).

    2. b.

      Filling phase. During this portion of the study the storage function of the bladder is evaluated. The recommendations are to report the following parameters:

      1. i.

        Technical factors:

        1. 1.

          Placement of abdominal pressure measurement (rectal, vaginal or stoma).

        2. 2.

          Whether the technical aspects were optimal or not. If the technique is not optimal the interpretation of the results could be erroneous (i.e., drop-out of rectal catheter or drifting of catheters).

        3. 3.

          If the technical aspects were suboptimal, did they interfere with the interpretation?

        4. 4.

          Quality of zeroing/subtraction during the entire test. Artifacts and channel drifting should be documented.

          1. a.

            Perfect

          2. b.

            Suboptimal for part of test.

          3. c.

            Suboptimal throughout test.

        5. 5.

          Confirmation of corresponding findings in bowel and bladder lines.

        6. 6.

          Significant prolapse and constipation can cause technical challenges and should be documented if this occurs. If prolapse reduction maneuvers during the study were utilized this should be documented.

        7. 7.

          Bladder sensation: Volume in milliliters at first bladder sensation, first desire, strong desire and maximum bladder/cystometric capacity. Pathological findings should be reported as urgency or pain related to bladder filling.

        8. 8.

          Bladder compliance:

          1. a.

            Changes in the detrusor pressure during filling to evaluate the bladder compliance. The bladder compliance changes should be reported as centimeters of water over change in volume.

          2. b.

            The bladder volume associated with DO episodes and the presence of urgency sensation or leakage should be recorded.

          3. c.

            The provided interpretation needs to take into consideration the relationship between the raw bladder and rectal pressure, not only the subtracted detrusor pressure, e.g., if there is any artifact affecting subtraction.

        9. 9.

          Patient symptoms:

          1. a.

            Presence or absence of symptoms using a preset checklist and the correlation of the symptoms with the bladder volumes.

          2. b.

            Whether the observations recorded (including patient-reported sensations/events) correspond to the clinically relevant question.

          3. c.

            Interpretation should include a comment about whether UDS testing was able to reproduce the patient’s symptoms and, if not, whether there were technical issues that may have interfered with the test.

        10. 10.

          Provocative maneuvers to assess incontinence.

          1. a.

            Patient position (supine, standing, sitting on commode) should be documented.

          2. b.

            In case of concomitant pelvic organ prolapse (POP), the provocative maneuvers should be performed with POP reduced and not reduced to assess voiding dysfunction. The POP reduction technique should be recorded (particular care needs to be taken not to occlude the urethra during POP reduction).

          3. c.

            Stress urinary incontinence maneuvers:

            1. i.

              The bladder volume during each of the provocative maneuvers should be recorded (e.g., cough, Valsalva, standing).

            2. ii.

              The leak point pressures and the specific maneuver (Valsalva vs. coughing) when the leakage is observed should be recorded in centimeters of water.

          4. d.

            Comment on leakage and any concurrent pressure changes.

            1. i.

              Whether leakage is synchronous or after cough (with pressure rise) suggestive of provoked detrusor overactivity.

          5. e.

            Overactive bladder/urgency urinary incontinence maneuvers:

            1. i.

              Bladder volume during rise in detrusor pressure should be recorded (bladder compliance).

            2. ii.

              Provocative maneuvers to elicit urgency should be recorded (e.g., handwashing, listening to running water, fast-filling with cold saline or other similar technique).

            3. iii.

              Any change of position during the investigation.

          6. f.

            Pressure flow or emptying phase.

            1. i.

              Checking of pressure lines prior to the pressure flow study.

              1. 1.

                Comment on height correction of domes (to maintain at lower border of the pubis).

            2. ii.

              The following parameters should be recorded:

              1. 1.

                Maximum flow (ml/s).

              2. 2.

                Characteristics of the flow (continuous, intermittent, fluctuating)

              3. 3.

                Detrusor pressure at maximum flow.

              4. 4.

                Presence or absence of abdominal strain during emptying.

              5. 5.

                Correlation with EMG activity, if done, during the study, at the moment prior and during permission to void.

              6. 6.

                Post void residual (PVR).

            3. iii.

              If patient is unable to void:

              1. 1.

                Document methods to initiate voiding (running water, provide privacy, removal of catheter).

Interpretation/conclusions

The following observations and conclusions should be recorded:

  • Were the patient’s pre-test symptoms reproduced?

  • Was the clinically relevant question answered?

  • Was a urodynamic diagnosis made?

    • The recommendation is to use the IUGA/ICS standardized diagnoses.

  • Management plan after urodynamics should also be documented.

    • Was the UDS question answered?

    • Is further investigation necessary?

    • Was a management plan formulated?

Did the urodynamic test change the clinical management?

Did the UDS help change the management or clarify the patient’s condition? This will help to assess the usefulness of the test. The recommendation also should specify the pre-UDS plan based on a predefined checklist. This list also includes an open-ended “other” option. These fields become useful in clinical audit and service evaluation.

Research/governance

It is important to maintain high clinical governance standards with UDS. The following are suggestions for audits that can be performed:

  • Completed report proformas can be audited to ensure the process is being followed with calibration and quality assurances.

  • Use of the urodynamics in the multidisciplinary team meeting (MDT).

  • Untoward events.

  • If for research was appropriate consent taken?

Conclusion

This document gives a standardized approach to reporting of urodynamics. The importance of this is based on urodynamics being part of a process and not an isolated event. Standardized reporting, like the WHO checklist, gives a framework to ensure that the test has been ordered appropriately and that the final report refers to the indication rather than merely the observations. As such, a standardized report has a better chance of being interpreted appropriately for the woman’s symptoms.