[Recommendations for the urodynamic examination in the investigation of non-neurological female urinary incontinence].

INDICATIONS FOR URODYNAMIC ASSESSMENT IN WOMEN: Urodynamic assessment is not useful for the diagnosis of female urinary incontinence which remains a clinical diagnosis. Before any form of surgery for pure stress urinary incontinence, evaluation of bladder emptying by determination of maximum flow rate and residual urine is recommended. In the presence of pure stress urinary incontinence with no other associated clinical symptoms, a complete urodynamic assessment is not mandatory, but can be helpful to define the prognosis and inform the patient about her vesicosphincteric function. On the other hand, a complete urodynamic assessment is recommended to investigate complex or complicated urinary incontinence, mainly in the case of: history of surgery for urinary incontinence. urgency with or without urine leakage, severe urinary incontinence, voiding abnormalities, negative cough test, decreased bladder capacity, suspected obstruction or decreased bladder contractility, failure of first-line treatment. PATIENT PREPARATION: The patient should be thoroughly informed about the examination procedure and its possible consequences. The patient should be advised to attend the examination with a normal desire to urinate. Urodynamic assessment must not be performed in the presence of untreated urinary tract infection. Antibiotic prophylaxis is not recommended. UROFLOWMETRY: The flowmeter must be regularly calibrated and must be installed in a quiet room. Whenever possible, uroflowmetry should be performed before cystometry with a normal desire to urinate. The patient should be advised to urinate normally without straining and by staying as relaxed as possible. During voiding, all of the stream must enter the flowmeter. The main parameters recorded are Qmax (expressed in ml/s), the voided volume (expressed in ml), and the appearance of the curve. The examination must be interpreted manually without taking into account the automated interpretation. GUIDELINES CONCERNING CYSTOMETRY EQUIPMENT: A three pressure line configuration is recommended. Bladder filling must be performed with a sterile liquid; filling with gas is no longer recommended. Bladder filling is ideally performed by a pump ensuring a sufficiently slow flow rate to avoid modifying bladder behaviour (< 50 ml/min). It is essential to determine and check the volume infused into the bladder. When a peristaltic pump is used, the bladder filling catheter must be adapted to the pump. Water or electronic transducers can be used to measure bladder pressure. Balloon catheters filled with air appear to be sufficiently precise to perform pressure measurements in a manometric chamber (during cystometry) but not in a virtual cavity such as the urethra (during the urethral pressure profile). Measurement of abdominal pressure is recommended, either via the infusion catheter or preferably by a rectal balloon catheter. GUIDELINES ON THE PRACTICAL CONDITIONS OF CYSTOMETRY: The equipment must be regularly calibrated. Make sure that the bladder is empty before starting cystometry. Transducers are zeroed at the superior extremity of the pubic symphysis for infused transducers and at atmospheric pressure for electronic and air transducers. Tubings must be correctly connected without kinks, bubbles or leaks. The catheter must be selected according to its technical characteristics, particularly its pressure loss. After filling for one or two minutes, the patient is asked to cough to ensure a similar increase in both abdominal pressure and bladder pressure. The following parameters are recorded: baseline detrusor pressure, first desire to void, detrusor activity, bladder capacity and bladder compliance. Measurement of bladder pressure during voiding is used to confirm whether or not the bladder is contractile, assess obstruction in the case of low urine flow rate with high bladder pressure, and detect abdominal straining. Good test conditions must be ensured in order to obtain good quality voiding. In the case of incoherent results, the bladder should be re-filled after checking the equipment. MEASUREMENT AND INTERPRETATION OF URETHRAL PRESSURE: To obtain a reliable measurement of urethral pressure, it is recommended to: Define the normal values used. Use a catheter smaller than 12 F. Perform a circumferential measurement. Use a catheter with an infusion rate of 2 ml/min. Remove the catheter at a rate of 1 mm/s. Perform the examination in the seating or supine position with a half-full bladder after reducing any prolapse. Repeat the measurements. THE FOLLOWING ELEMENTS MUST BE TAKEN INTO ACCOUNT WHEN INTERPRETING AN URETHRAL PRESSURE PROFILE: The functional urethral length is neither a diagnostic criterion nor a prognostic criterion of urinary incontinence. The urethral pressure profile cannot be considered to be a useful test for the diagnosis of female urinary incontinence. However, in combination with clinical criteria, it is predictive of the results of female stress urinary incontinence surgical repair techniques. The pressure transmission ratio is neither a diagnostic criterion nor a prognostic criterion of urinary incontinence.