Comparing Voiding Trials After Midurethral Sling for Stress Incontinence

Urinary incontinence is a prevalent health and quality of life concern affecting an estimated 49.6% of women over the age of 20 years in the USA. (1) Of these, 49.8% describe pure stress urinary incontinence (SUI) and 34.3% report mixed stress and urgency urinary incontinence. (1)

Midurethral sling (MUS) surgery is used to treat women with SUI, but accepted protocols for voiding trials after midurethral sling placement do not exist. Primarily, many surgeons measure postvoid residual (PVR) urine volume. This is done by retrograde filling of the bladder with a predetermined amount of normal saline or water. The catheter is then removed and the patient is permitted to void into a collection basin. The amount in the basin is subtracted from the filled amount. The need for catheterization is generally based on arbitrarily determined ratios of voided urine to PVR or postoperative.

The acceptable amount voided during catheterization varies among practitioners. In a study by Kleeman et al, the patient was required to void >50% of volume filled during retrograde fill for discharge from hospital without an indwelling Foley catheter (2). Pulvino et al, required that the patient void > 2/3 the amount of the volume placed during retrograde fill (3). The force of stream trial (FAST) does not prioritize amount voided, but rather the patient's subjective force of stream. The bladder is retrograde filled with 300cc normal saline or water and the patient is instructed to void.. Using FAST, a patient uses a VAS scale to quantify her force of stream. If she states that her Force of Stream (FOS) is >50% stronger than prior to surgery, independent of the amount voided, she is discharged without a catheter. If the FOS is <50% a PVR via bladder scan is performed. If her PVR is <500cc the patient was discharged home without a catheter in place. If the PVR, via bladder scan was > 500cc she was discharged with a catheter. Ingber et. Al. showed the FAST method was a safe method for predicting postoperative voiding dysfunction and/or urinary retention. No patients presented to the office or emergency room for voiding dysfunction or urinary retention (4).

Urinary retention is a concern of many surgeons who perform midurethral sling surgery; 25% of urologists routinely discharge patients home with a catheter and 31% admit patients overnight or for 23 hour observation, with 42% doing so for the primary purpose of facilitating the voiding trial. (5)

Published catheterization rates for these protocols can approach 39%. (6,7) Temporary catheterization does not pose a significant medical risk, but it is perceived as an inconvenience and source of discomfort for many patients. Proper care of an indwelling foley catheter requires extra teaching from nursing and/or house staff.

No randomized control trials (RCT) have been performed comparing the FAST method to the traditional retrograde voiding trial. In our practice we assess postoperative voiding function using the retrograde fill with 300cc saline or water. We also require a 2/3 quantity voided for discontinuation of catheter.

All patients after outpatient midurethral sling or vaginal prolpase surgery must complete a voiding trial if they are to be discharged without a catheter. This is standard of care and followed in our practice. We would like to compare both postoperative voiding trials in patients who have undergone surgical repair concomitant midurethral sling with or without anterior colporrhaphy. We will include those patients who also had an anterior colporrhaphy at time of sling placement as this procedure is commonly performed at the time of sling placement for stablization of MUS. We will assess the number of emergent or unexpected visits for voiding dysfunction. An unexpected visit to the office will be defined as any visit outside of the patient's prior scheduled postoperative visits.

Inclusion criteria

• Postoperative patients after placement of midurethral sling (retropubic sling or transobturator) with or without anterior or posterior colporrhaphy.
• Ability to provide informed consent and complete all study requirements

Exclusion criteria

• Patients who underwent a surgery that requires long term catheterization (i.e fistula repair or urethral diverticulum)
• Patients who sustained a cystotomy during surgery as our divisional protocol is to send these patients home with a Foley catheter for 5-14 days without a voiding trial
• Patients who had an apical repair for pelvic organ prolapse (Uterosacral vaginal vault suspension, Abdominal sacral colpopexy, sacrospinous ligament fixation)