Randomized controlled trial of benzocaine versus placebo spray for pain relief at hysterosalpingogram

Abstract

Many women experience pain during hysterosalpingogram (HSG). This prospective, randomized, double-blinded, placebo-controlled study assessed whether the use of benzocaine spray during HSG is associated with reduced pain as compared with placebo. Thirty women presenting for HSG were enrolled and randomized to either benzocaine or saline spray. Treatment groups were similar in age, race, parity, pre-procedure oral analgesic use and history of dysmenorrhoea and/or chronic pelvic pain. Median change in pain score from baseline to procedure was 50.6 mm (−7.4 to 98.8 mm) in the benzocaine group and 70.4 mm (19.8 to 100 mm) in the placebo group. There was no difference between groups after adjusting for history of dysmenorrhoea. There was no difference in resolution of pain in benzocaine versus placebo groups at 5 min post procedure – median pain score difference – 11.1 (−90.1 to 18.5) versus −37.0 (−100 to 1.2) – or at 30 min post procedure. Satisfaction scores did not differ by treatment and did not correlate with pain score during the procedure (rho = 0.005). The use of benzocaine spray does not significantly improve pain relief during HSG nor does it hasten resolution of pain post HSG. Of interest, patient satisfaction was not correlated with pain.

Comparison of Four Different Pain Relief Methods during Hysterosalpingography: A Randomized Controlled Study

“…Original research articles in the literature were analyzed before the sample size was calculated, but none of the articles compared the three topical anesthetics among groups. The study by Bachman et al ( 20 ) was used for the calculations, with a difference of at least 1.3 on a VAS with a highest SD of 1.2 being regarded as clinically significant (α=0.05, power = 0.80), and a sample size of at least 14 in each group. A one-way ANOVA test was used for analysis.…”