(273) The Use of In-Office Nitrous Oxide to Aid in Diagnosing Hypertonic Pelvic Floor and Improve Patient Comfort with Pelvic Exams
Authors: Paulsen O , Kumar P , Tomaszewski A , Sverdlove R , Johnson C , Marantidis J , Sussman R , Quaile H , Rubin R 
Published: February 2024

Abstract

Introduction
Nitrous oxide is an anesthetic, anxiolytic, and analgesic commonly used for general and dental anesthesia, sedation, and severe pain. Studies show that nitrous oxide is also used in several in-office gynecological and urological procedures as a sedative and anxiolytic agent with a safer drug profile than other anesthetic agents. It is also being trialed as a treatment for mood disorders. Nitrous oxide does not render individuals unconscious, making it a more favorable option for stressful and painful medical procedures than general anesthesia because it allows the patient to feel more in control of their body and aware of the proceedings.

Objective
To analyze the use of in-office nitrous oxide during medical procedures and evaluate its effectiveness in reducing pain and anxiety levels to predict the utility of it during pelvic exams in patients with vestibulodynia.

Methods
A literature review was performed through the PubMed database between 2007-2022. The authors independently and thoroughly screened abstracts and full-text articles and assessed the relevant medical literature that acknowledged the use of nitrous oxide in in-office medical procedures. Key terms used to refine the search include [“nitrous oxide in medical procedures”], [“nitrous oxide in gynecology”], [“nitrous oxide in urology”].

Results
One study explored the use of nitrous oxide during childbirth in women diagnosed with PTSD, and the results were significant for nitrous oxide reducing PTSD symptom severity. Multiple studies suggest the use of nitrous oxide during dental procedures reduces patient anxiety; one specifically measured sixty anxious patients pre- and post-endodontic procedures and noted a significant reduction in anxiety during the procedure with the use of nitrous oxide. Various studies of gynecological and urological procedures report the successful use of nitrous oxide in reducing peri-procedural pain compared to other analgesic alternatives. A common example is its use during intrauterine device insertion, which is correlated with higher patient satisfaction as it decreases pain. Additionally, a study among patients undergoing extracorporeal shockwave lithotripsy found no significant difference between the use of meperidine, an opioid, and nitrous oxide in post-procedural Visual Analog Scale pain scores with no adverse events reported in the nitrous oxide group. Another study revealed that using local anesthesia in transrectal prostate biopsies resulted in some patients experiencing notable anxiety and pain. At the same time, no such relationship was observed among patients who received nitrous oxide before this procedure.

Conclusions
Vestibulodynia is a subset of genitopelvic pain isolated to the vulvar vestibule. Vestibulodynia has three proposed etiologies: tissue neural proliferation, musculoskeletal, and hormonally mediated. Discriminating these three etiologies can be difficult, especially when a proper pelvic exam cannot be achieved due to patients’ discomfort. The three etiologies are biologically intertwined, often resulting in vestibulodynia patients experiencing pelvic floor hypertonicity without regard to specific etiology. A painful pelvic exam is stressful and often an anxiety-producing experience for patients with pelvic hypertonicity and vulvodynia. Hence, with the data provided, we suspect that nitrous oxide will be a useful treatment option to mitigate these consequences for the patient, with the added benefit of easing the exam for the provider, leading to a more accurate diagnosis.

Disclosure
No.