Paracervical block as pain treatment during second-trimester medical termination of pregnancy: an RCT with bupivacaine versus sodium chloride

• Published in: Human reproduction (Oxford) 2016-01, Vol.31 (1), p.67-74
• Main Authors: Andersson, I.-M., Benson, L., Christensson, K., Gemzell-Danielsson, K.
• Format: Article
• Language: English
• Subjects: Abortion, Induced - adverse effects; Adult; Anesthesia, Obstetrical - methods; Anesthetics, Local - administration & dosage; Anesthetics, Local - pharmacology; Bupivacaine - administration & dosage; Bupivacaine - pharmacology; Double-Blind Method; Female; Humans; Medicin och hälsovetenskap; Outcome Assessment (Health Care); Pain Measurement; Pregnancy; Pregnancy Trimester, First; Pregnancy Trimester, Second; Sodium Chloride - administration & dosage; Sodium Chloride - pharmacology; Young Adult
• ISSN: 0268-1161; 1460-2350; 1460-2350
• DOI: 10.1093/humrep/dev286

Abstract STUDY QUESTION Can paracervical block (PCB) administered before the onset of pain decrease women's pain experience during second-trimester medical termination of pregnancy (MToP)? SUMMARY ANSWER There were no clinically significant differences between groups receiving PCB with bupivacaine or saline with regard to the highest and lowest pain intensity, morphine consumption or induction-to abortion interval. WHAT IS KNOWN ALREADY The most common side effect of misoprostol is pain; nevertheless, there are sparse studies in pain and pain treatment during MToP, especially in second-trimester abortion. Pain reported in second-trimester medical abortion is often intense, and peaks when the fetal expulsion occurs. STUDY DESIGN, SIZE, DURATION A double-blinded RCT was carried out from May 2012 until April 2015. A power calculation was based on a previous pilot study showing that the proportion of women with severe pain [visual analogue scale (VAS) ≥7] was 63%. A clinically significant reduction was considered to yield 35% with severe pain, and with a power of 80% and significance level of 5% (two-sided) 112 women were needed. Accounting for a 20% drop-out rate, a total of 140 women were needed. The primary outcome, pain intensity measured as any VAS ≥7, was analysed using a generalized estimating equations model. The level of significance was set to P < 0.05 two-sided. A computer generated randomization list with block size of 10 was used. The treatment allocation was placed in a sealed, opaque, envelope and picked consecutively. PARTICIPANTS/MATERIALS, SETTING, METHODS A total of 589 women attending a gynaecological clinic had a second-trimester abortion during the study period and 276 were invited to participate. A total of 113 women undergoing abortion from 13 weeks of gestation and above were recruited, of which 55 were randomly allocated to receive a PCB with bupivacaine and 58 a PCB with sodium chloride 1 h after the first dose of misoprostol. The full analysis set (FAS) population was defined as all randomized women that had at least one value for any of the outcomes (n = 102). The per-protocol (PP) population was defined as a subset of the FAS excluding patients with major protocol deviations or without a value for the primary outcome (n = 99). Pain was measured by VAS at misoprostol initiation (baseline) and repeated every 30 min until fetal expulsion. The primary outcome was the highest VAS pain intensity at any time point. MAIN RESULTS AND THE R