Esketamine administered epidurally as an adjuvant to epidural ropivacaine for labour analgesia: a prospective, double-blind dose-response study.

Abstract

<h4>Objective</h4>To investigate the efficacy of esketamine as an adjuvant to epidural ropivacaine for labour analgesia by determining its effect on the median effective concentration (EC₅₀) in a 20 ml volume of ropivacaine.<h4>Design</h4>A prospective, double-blind dose-response study.<h4>Setting</h4>This study was conducted in Women's Hospital, School of Medicine, Zhejiang University, China.<h4>Participants</h4>One hundred and fifty parturients who requested epidural analgesia were recruited in this study to randomly receive epidural ropivacaine alone or with esketamine of 0.2 mg ml^-1, 0.3 mg ml^-1, 0.4 mg ml^-1 or 0.5 mg ml^-1, respectively.<h4>Primary and secondary outcome measures</h4>The primary outcome, EC₅₀ of ropivacaine, was determined using an up-down sequential allocation technique. The secondary outcomes were analgesia characteristics, Ramsay Sedation Scale score, labour duration, caesarean section rate and adverse effects.<h4>Results</h4>The EC₅₀ of ropivacaine with the addition of esketamine at concentrations of 0.3 mg ml^-1, 0.4 mg ml^-1 and 0.5 mg ml^-1 resulted in significant reductions in the EC₅₀ of ropivacaine to 0.050%, 0.044% and 0.043%, respectively, from baseline (esketamine 0 mg ml^-1) (p<0.0001). However, reductions of the EC₅₀ of ropivacaine were similar among the groups with esketamine of 0.3 mg ml^-1, 0.4 mg ml^-1 and 0.5 mg ml^-1 (p>0.05). The Ramsay Sedation Scale score was higher and more dizziness was observed in the Group of esketamine 0.5 mg ml^-1 compared with all other groups (p<0.0001). During the peripartum period, no differences in sensory blockade level, Bromage score, labour duration and percentage of caesarean delivery were found among the groups.<h4>Conclusions</h4>Under the conditions of this study, the addition of epidural esketamine of 0.3 mg⋅mL^-1, 0.4 mg⋅mL^-1 and 0.5 mg⋅mL^-1 offered a similar ropivacaine dose-sparing effect; 0.5 mg⋅mL^-1 of esketamine produced more adverse effects.<h4>Trial registration number</h4>ChiCTR2100054348.

Topics & conditions

Detected automatically by Psychedelic Commons from the title and abstract, not labels from the source. They may be incomplete.

Keywords