Retropubic midurethral slings are a common and effective treatment for stress urine incontinence. The trocar that is attached to the mesh material can hit the bladder which is called a perforation. While there are no known long-term adverse outcomes from trocar-induced bladder perforations, it can prolong operative time and bleeding. At academic institutions, it has been reported that trocar-induced perforations occurs in the range of 14-34% of the time. This study is a randomized controlled trial to see if an intervention can decrease trocar-induced bladder perforation rates. The primary outcome of this study is to measure trocar-induced bladder perforations in subjects undergoing a retropubic midurethral sling. Subjects would be randomized to either receive the hydrodissection in a standardized manner or to not receive it. Secondary outcomes include bothersome urinary symptoms, pain, estimated blood loss during surgery, and voiding trial results

All female adult subjects presenting to the UMass urogynecology clinic for scheduled retropubic midurethral sling surgery will be eligible for recruitment. Subjects will also be recruited if they are fluent in English and/or Spanish, and able to fill out consent and questionnaires. Subjects would be excluded if they are limited English or Spanish proficiency to participate in the study, pregnant, or having concurrent surgery for malignancy.

At the time of enrollment which would be done at a preoperative visit, subjects would be asked to fill out a baseline urinary symptom questionnaire (UDI-6). On the day of surgery, each subject would be randomized via computer-generated randomization table to either the intervention group (receiving retropubic hydrodissection) or no intervention group.

The method of hydrodissection is described as the following: After the peri-urethral dissection is performed and the bladder is continuously drained and emptied via Foley catheter, a 20-gauge spinal needle is used to administer a total of 60ml of sterile injectable saline in the retropubic space. The surgeon will insert the needle approximately 2-3cm on each side of the midline just above the pubic symphysis. With another hand in the vagina, the surgeon will guide the needle to the retropubic space and infiltrate along the anticipated path of the trocar and inject 30ml of saline in the retropubic space on each side.

Intraoperative data collected includes number of trocar-induced bladder

Inclusion Criteria:

• scheduled for retropubic midurethral sling

Exclusion Criteria:

• cognitive or intellectual impairment that would hinder ability to complete questionnaires or be consented
• having concurrent surgery for malignancy

female