Analgesia Using Transcutaneous Electric Nerve Stimulation in Office Bladder Chemodenervation, a Randomized Controlled Trial.

Importance: Office bladder chemodenervation, performed via cystoscopy with intradetrusor onabotulinumtoxinA (BOTOX) injections, is a common treatment for overactive bladder/urge urinary incontinence. Transcutaneous electric nerve stimulation (TENS) has shown to provide analgesia during office hysteroscopy. Adjuvant analgesia using TENS during bladder chemodenervation has not been studied.

Objective: The primary outcome is a clinically significant (10-mm) difference in pain visual analog scale (VAS) measurements during injections for chemodenervation using active TENS compared with placebo TENS. We hypothesize that active TENS use will significantly change pain VAS scores. Secondary outcomes include 5-point pain Likert scale, satisfaction 10-point scale, and adverse events.

Study design: This was a double-blind randomized control trial of men and women with urinary urge incontinence undergoing office chemodenervation performed in an academic and private setting. Participants were randomized into 2 groups: chemodenervation with active TENS or placebo TENS. Power calculation determined 100 patients would be required detect a difference of 10 mm on pain VAS.

Results: One hundred one (85 female and 16 male) participants were recruited. No differences were noted in the demographics. Participants in the active TENS group reported a difference of greater than 10 mm in pain VAS scores (48 ± 23 vs 31 ± 23, P = 0.01). Satisfaction index scores were high but no difference was noted between groups (8.6 vs 8.7, P = 0.68).

Conclusions: Most participants were eligible to use TENS units. Transcutaneous electric nerve stimulation is a safe and noninvasive adjuvant analgesia option for patients undergoing this procedure. Lower pain levels and high satisfaction rates suggest that this is an additional analgesic option during outpatient chemodenervation.