Patient controlled analgesia with remifentanil versus epidural analgesia in labour: randomised multicentre equivalence trial

Abstract

Objective To determine women’s satisfaction with pain relief using patient controlled analgesia with remifentanil compared with epidural analgesia during labour. Design Multicentre randomised controlled equivalence trial. Setting 15 hospitals in the Netherlands. Participants Women with an intermediate to high obstetric risk with an intention to deliver vaginally. To exclude a clinically relevant difference in satisfaction with pain relief of more than 10%, we needed to include 1136 women. Because of missing values for satisfaction this number was increased to 1400 before any analysis. We used multiple imputation to correct for missing data. Intervention Before the onset of active labour consenting women were randomised to a pain relief strategy with patient controlled remifentanil or epidural analgesia if they requested pain relief during labour. Main outcome measures Primary outcome was satisfaction with pain relief, measured hourly on a visual analogue scale and expressed as area under the curve (AUC), thus providing a time weighted measure of total satisfaction with pain relief. A higher AUC represents higher satisfaction with pain relief. Secondary outcomes were pain intensity scores, mode of delivery, and maternal and neonatal outcomes. Analysis was done by intention to treat. The study was defined as an equivalence study for the primary outcome. Results 1414 women were randomised, of whom 709 were allocated to patient controlled remifentanil and 705 to epidural analgesia. Baseline characteristics were comparable. Pain relief was ultimately used in 65% (447/687) in the remifentanil group and 52% (347/671) in the epidural analgesia group (relative risk 1.32, 95% confidence interval 1.18 to 1.48). Cross over occurred in 7% (45/687) and 8% (51/671) of women, respectively. Of women primarily treated with remifentanil, 13% (53/402) converted to epidural analgesia, while in women primarily treated with epidural analgesia 1% (3/296) converted to remifentanil. The area under the curve for total satisfaction with pain relief was 30.9 in the remifentanil group versus 33.7 in the epidural analgesia group (mean difference −2.8, 95% confidence interval −6.9 to 1.3). For who actually received pain relief the area under the curve for satisfaction with pain relief after the start of pain relief was 25.6 in the remifentanil group versus 36.1 in the epidural analgesia group (mean difference −10.4, −13.9 to −7.0). The rate of caesarean section was 15% in both groups. Oxygen saturation was significantly lower (SpO 2 <92%) in women who used remifentanil (relative risk 1.5, 1.4 to 1.7). Maternal and neonatal outcomes were comparable between both groups. Conclusion In women in labour, patient controlled analgesia with remifentanil is not equivalent to epidural analgesia with respect to scores on satisfaction with pain relief...

Anterior Suprascapular Nerve Block Versus Interscalene Brachial Plexus Block for Shoulder Surgery in the Outpatient Setting

“…At the advice of reviewers and the journal's editors, we modified this to have a properly defined multiple outcome based on the requirement that pain not be inferior using the SSNB and that grip strength be superior. Following the recommendations of Freeman et al, 9 we used the area under the curve (AUC) from the NRS for the pain component and chose 10% of the total scale (1.1 units) as margin of noninferiority. Grip strength was assessed using the Modified Medical Research Council Scale for measuring hand muscle strength.…”

Patient satisfaction between remifentanil patient‐controlled analgesia and epidural analgesia for labor pain

“…Freeman et al. recently confirmed that EA is superior as an analgesic during delivery; however, it is not clear whether better analgesia actually leads to increased satisfaction with the entire labor and delivery. Measurement of pain and satisfaction during labor is complex.…”

“…In addition to the traditional forms of labor analgesia such as pethidine (meperidine) and EA, RPCA is gaining popularity for the purpose of labor analgesia. This is noteworthy because studies comparing RPCA with EA found significantly higher pain scores for the RPCA group . Four studies comparing RPCA with EA showed that EA is a better analgesic, but maternal satisfaction scores were comparable for both, with no differences in type of delivery or neonatal outcome .…”

“…Remifentanil patient‐controlled analgesia (RPCA) has been demonstrated to be an effective method of pain relief with favorable pharmacokinetic properties for women during labor . Remifentanil is an ultra short‐acting μ‐opioid that is metabolized rapidly through non‐specific tissue esterases in adults and newborns .…”

“…Waldenstrom found that measurements of satisfaction with childbirth made soon after delivery might be biased. Recently, a large randomized multicenter trial performed in the Netherlands found that both the woman's satisfaction and the pain relief performance with RPCA was significantly less than with EA. Scores of satisfaction with the pain were limited to the period during labor and directly post labor.…”