6- Postvoid Residual Urine Volume
In the Value of Urodynamic Evaluation trial, only women with a postvoid residual urine volume of less than 150 mL were included in the study as meeting the a priori definition of uncomplicated SUI (11). The presence of an elevated postvoid residual urine volume can indicate a bladder-emptying abnormality or incontinence associated with chronic urinary retention (previously referred to as overflow incontinence). An elevated postvoid residual urine volume in the absence of POP is uncommon and should trigger an evaluation of the bladder-emptying mechanism, usually with a pressure-flow urodynamic study.
Multichannel Urodynamic Testing
Preoperative multichannel urodynamic testing is not necessary before planning primary anti-incontinence surgery in women with uncomplicated SUI, as indicated by observed urinary leakage from the urethra by provocative stress measures, a normal urinalysis result (without urinary tract infection), no POP beyond the hymen, and a normal postvoid residual urine volume. Randomized controlled trial results have demonstrated that in women with uncomplicated SUI, outcomes 1 year after midurethral sling surgery were the same for those who had a basic office assessment performed by trained pelvic floor health care providers compared with those who had a preoperative evaluation that included urodynamic test-ing (11). However, women who have complicated SUI (Table 1) may benefit from multichannel urodynamic testing and other diagnostic tests before initiation of treatment, especially surgery. Determination of the need for additional diagnostic testing before surgery should be based on clinical judgment after completion of the basic UI evaluation outlined in this document. Clinical judgment should guide the health care provider’s decision to perform preoperative multichannel urodynamic testing or to refer the patient to a specialist with appropriate training and experience in female pelvic medicine and reconstructive surgery.