A Randomized Double Blind Placebo Controlled Study to Assess the Efficacy of Fundal Block Analgesia During Radiofrequency Endometrial Ablation

STUDY OBJECTIVE: To assess the efficacy of the addition of a hysteroscopic fundal block on patient's perception of intra-operative pain during NovaSure endometrial ablation in an ambulatory setting. DESIGN: Single centre, randomized, double-blind, placebo-controlled trial with a parallel design and a 1:1 treatment allocation ratio. SETTING: Canadian gynecologic ambulatory-care clinic. PARTICIPANTS: A total of 100 premenopausal female patients with abnormal uterine bleeding undergoing an ambulatory NovaSure endometrial ablation. INTERVENTION: Hysteroscopic fundal injections with 10 mL 1% lidocaine (treatment group) or hysteroscopic fundal injections with normal saline (placebo group). RESULTS: There was no difference in Numeric Rating Scale (NRS) for pain scores at 30 seconds, 60 seconds, and 1-hour postprocedure in the placebo and fundal block groups (p = .08; p = .28; p = .09). Secondary subgroup analysis revealed significantly higher NRS scores in those with a self-reported history of dysmenorrhea (NRS score >5) who received placebo compared to the lidocaine fundal block at 30 and 60 seconds (p = .02; p = .03). The procedure was found to be acceptable to the majority of participants and 95.6% would recommend the procedure to someone else with no difference between groups. There was no difference in use of intraoperative analgesics and sedatives, postoperative pain, or adverse events between the groups. CONCLUSION: When using parenteral conscious sedation and a paracervical block, the addition of a hysteroscopic fundal block during ambulatory NovaSure endometrial ablation does not improve NRS pain scores. Select patients, including those with dysmenorrhea, may benefit from the addition of a hysteroscopic fundal block.