Comparison of Efficacy Between Nitrous Oxide (n2o) Analgesia and Pericervical Analgesia in Outpatient Operative Hysteroscopy With Miniresector: a Randomized Clinical Pilot Study

Pain is the primary cause of hysteroscopy failure. It can be attributed to multiple causes, such as manipulation of the cervical canal , uterine distention due to the liquid distension media used during the procedure , operating procedures on the endometrium (as a possible cause of uterine contraction) , until the release of prostaglandins following manipulation of the cervix and uterine distension.

There are few studies in the literature that have compared the various methods of pain control during the hysteroscopic examination. Among these, Ahmad et al., for example, compared the use of the paracervical block and inhalation anesthesia during hysteroscopy: although both proved to be effective in controlling pain, the paracervical block was associated with a greater number of complications. More recently, Solano et al. they defined how the administration of nitrous oxide was equally effective (but with many more advantages) to the paracervical block with 1% lidocaine in controlling pain during hysteroscopy performed using the Bettocchi hysteroscope.

However, for the purposes of this research it is important to take two aspects into consideration:

• all the studies in the literature that compared the various pain control methods during hysteroscopy were conducted using the Bettocchi Hysteroscope and not the Miniresector;
• more in detail, there are no studies comparing the use of nitrous oxide and pericervical analgesia during outpatient operative hysteroscopy with miniresector.

Objective This clinical trial will have the aim of evaluating and comparing the effectiveness of two methods (analgesia with nitrous oxide and pericervical analgesia, excluding the use of paracervical block due to the increased risk of complications reported in the literature1) in the control of pain caused during Outpatient Operative Hysteroscopy maneuvers with Miniresector.