A Randomized, Placebo-controlled Trial of Nitrous Oxide During In-office Bladder Botox Injections

A Randomized, Placebo Controlled Trial of Nitrous Oxide/Oxygen Plus Standard Care Versus Standard Care Alone During In-office Intradetrusor onabotulinumtoxinA (Botox) Injections

The goal of this clinical trial is to assess if a mix of nitrous oxide and oxygen can improve pain control during bladder Botox injections. The primary question it aims to answer is: Does using nitrous oxide lower the overall level of pain during the procedure?

Researchers will compare a 50:50 nitrous oxide/oxygen mixture (administered with the Pro-Nox system) plus standard care (with lidocaine in the bladder) to sham mask plus standard care to see if nitrous oxide works better for lowering pain.

Participants will:

• Receive their bladder Botox injection in the office setting
• Either use nitrous oxide/oxygen plus standard care during the procedure, or sham mask plus standard care
• Answer brief questions about pain, anxiety, satisfaction, and willingness to repeat the procedure

This study will assess if a 50:50 nitrous oxide and oxygen mixture can lower pain in women undergoing in-office bladder onabotulinumtoxinA (Botox) injections. Many people report pain during this procedure, and pain is a common reason not to repeat the procedure. Nitrous oxide is a fast-acting inhaled analgesic that is used commonly in the office setting.

This randomized controlled trial will compare nitrous oxide/oxygen plus standard care with sham mask plus standard care. Participants assigned to the nitrous oxide group will receive nitrous oxide via the Pro-Nox device during the procedure. Both, participants assigned to the nitrous oxide group and the standard care alone group, will receive the usual lidocaine instilled in the bladder for at least 15 minutes.

The study will measure participants overall pain during the procedure. It will also assess peak pain, overall anxiety, satisfaction, willingness to repeat, interest in using nitrous oxide in future bladder Botox procedures, and side effects. Nitrous oxide is expected to wear off within minutes, allowing participants to leave the clinic without restrictions.

This research study would be first randomized-controlled trial to evaluate nitrous oxide for pain management during this common in-office procedure.

Inclusion Criteria:

• Adult women ≥18 years old scheduled for in-office intradetrusor botulinum toxin injection and able to consent.

Exclusion Criteria:

• Known/suspected vitamin B12 or folate deficiency or high-risk state (e.g., pernicious anemia, malabsorption, post-bariatric or strict vegan without supplementation)
• currently pregnant
• severe/unstable pulmonary disease or baseline hypoxemia requiring supplemental home oxygen
• eye or ear surgery in the last six weeks
• trapped-air conditions (e.g., untreated pneumothorax, bowel obstruction)
• severe active otitis/sinus disease
• inability to follow directions
• history of adverse reaction to nitrous oxide