A double‐blind randomised comparison of intravenous patient‐controlled remifentanil with intramuscular pethidine for labour analgesia*

Abstract

SummaryIn a prospective, double-blind, randomised controlled trial, we compared the efficacy of patientcontrolled analgesia using remifentanil (25-30 lg per bolus) with intramuscular pethidine (50-75 mg) for labour analgesia in 69 parturients. Parturients receiving patient-controlled analgesia reported less pain than those receiving intramuscular pethidine throughout the study period (p < 0.001), with maximal reduction in visual analogue pain score at 2 h after commencement of analgesia (mean (SD) 20 (17) in the patient-controlled analgesia group and 36 (22) in the intramuscular pethidine group. The median (95% CI) time to the first request for rescue analgesics was significantly longer with patient-controlled analgesia (8.0 (6.8-9.2) h) compared with intramuscular pethidine (4.9 (3.8-5.4) h, p < 0.001). Maternal satisfaction scores were also higher with remifentanil compared with intramuscular pethidine (p = 0.001). There was no report of sedation, aponea or oxygen desaturation in either group, and Apgar scores were similar between groups. We conclude that patient-controlled analgesia with remifentanil provides better labour analgesia and maternal satisfaction than intramuscular pethidine. At this dose, maternal and fetal side effects were uncommon.

The analgesic efficacy of remifentanil for labour. Systematic review of the recent literature

“…The combined data from the meta-analysis shown in Table 6, revealed a statistically significant decrease in the VAS in the remifentanil group ( 27 Douma et al 33 Douma et al 43 El-Kerdawy et al 42 Evron et al 28 Evron et al 35 Ismail et al 44 Ng et al 40 Stocki et al 17 Štour et al 15 Thurlow et al 46 Tveit et al 34 Volikas et al 26 Volmanen et al 37 Volmanen et al 41 References Difference in means and 95% CI Comparison of IV opioid analgesia, Entonox, neuraxial analgesia on neonatal outcome Egan 13 Pharmacokinetics and pharmacodynamics of remifentanil Leong et al 38 A comparison between remifentanil and meperidine for labor analgesia Hill et al 55 The use of remifentanil in obstetric anaesthesia and analgesia Hinova et al 56 Effi cacy of remifentanil as a labor analgesic Volmanen et al 57 Comparison of paracervical block, pudendal block, IV remifentanil and nitrous oxide Kranke et al …”

“…There were no differences in the incidence of decreased saturation below 95% or in maternal sedation. Some studies found no difference in cardiotocograph interpretation 33,40 . On the other hand, one study showed a lower incidence of non-physiological cardiotocograph when remifentanil was administered 35 .…”

“…15 ). Lock out interval (interval in which the pump does not respond to parturient requirements) varied between 1 and 3 min with the exception of two studies, where the lock out interval was 4.5 min and 5 min 40,42 . A maximum average single dose of 0.7 μg/kg was published by Tveit.…”

“…A fixed dose without the option of reacting to actual need can therefore lead to either underdosing with unsufficient pain relief or overdosing associated with side-effects 27,46 . Some studies refute this concern 33,40,43 . The question of preferences of fixed dose or variable dose therefore remains open.…”

“…Some publications do not describe a higher incidence in the case of remifentanil 14,15,17,24,31,34 . The occurrence of dizziness may disable further use of remifentanil due to risk of falling during verticalization 40,41 . An incidence of maternal desaturation under 95% is published in 24 -74% of cases 17,30,31,33,41,46 .…”