Meperidine Compared With Nitrous Oxide for Intrapartum Pain Relief in Multiparous Patients: A Randomized Controlled Trial.

OBJECTIVE: To compare the efficacy and adverse effects of intravenous meperidine and inhaled nitrous oxide for intrapartum analgesia in multiparous patients. METHODS: This randomized controlled trial was conducted in the delivery ward of a university teaching medical center in Afula, Israel. Multiparous patients with term, singleton pregnancies who were in labor were randomized in a 1:1 ratio to 50 mg intravenous meperidine or inhaled nitrous oxide. The primary outcome was pain intensity 20-30 minutes after analgesic administration, measured on a visual analog scale (VAS) from 0 to 10 cm. Secondary outcomes included the need for additional analgesia, labor length, delivery mode, patient satisfaction, and maternal and neonatal adverse effects. To detect a 1-cm (±2.6) difference in VAS score between the groups, 214 total participants were needed to achieve 80% power with an alpha of 0.05. RESULTS: From August 2016 through May 2019, 214 participants were enrolled. Fourteen were excluded after randomization. Of the 200 analyzed, 102 received nitrous oxide, and 98 received intravenous meperidine. Demographic and obstetric variables were comparable between the two groups. The VAS score 20-30 minutes after analgesic administration did not differ between the groups (7.7±2.3 cm and 7.6±2.7 cm in the nitrous oxide and meperidine groups, respectively, P=.89). There were no significant differences between the groups in the rate of additional analgesic use, labor length, delivery mode, Apgar scores, rate of breastfeeding, patient satisfaction, or maternal and neonatal adverse effects. CONCLUSION: Pain intensity was comparable in multiparous patients 20-30 minutes after administration of meperidine and nitrous oxide. Adverse effects were also comparable. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, NCT02783508.

Effect of intermittent versus continuous bladder catheterization on duration of the second stage of labor among nulliparous women with an epidural: a randomized controlled trial.

INTRODUCTION AND HYPOTHESIS: Catheterization type among women laboring with epidural analgesia who develop bladder retention has been reported to affect labor duration and mode of delivery. We aimed to compare the effect of continuous bladder catheterization (CC) with that of intermittent bladder catheterization (IC) on the duration of the second stage of labor. METHODS: In a randomized trial, term nulliparous women with singleton gestation who requested epidural analgesia and were unable to void spontaneously were eligible and randomized to either CC or IC. Epidural analgesia was maintained with patient control until delivery. The primary outcome was duration of the second stage of labor. Secondary outcomes were mode of delivery, and incidences of postpartum hemorrhage, bladder retention, and infection. It was assumed that, compared with IC, CC might better prevent bladder distention, which is thought to delay fetal descent. A sample size of 90 women in each group was calculated to be adequate to detect a reduction of 30 min in the duration of the second stage of labor among the CC group. RESULTS: Between July 2014 and May 2015, a total of 184 women were randomized and included in the analysis; 90 and 94 women in the CC and IC groups respectively. Demographic and obstetric characteristics were similar. Duration of the second stage was 121.0 ± 89.4 and 131.9 ± 87.5 min in the CC and IC groups respectively (p = 0.29). The two groups did not differ significantly with regard to delivery mode, third-stage duration, and incidences of postpartum hemorrhage, bladder retention, and urinary tract infection. CONCLUSION: Duration of the second stage of labor is not influenced by bladder catheterization type in nulliparous women receiving an epidural.