Comparison of labor analgesia efficacy between single-orifice and multiorifice wire-reinforced catheters during programmed intermittent epidural boluses: a randomized controlled clinical trial

We compared analgesic outcomes between single-orifice and multiorifice wire-reinforced catheters under 480 mL/hour delivery rate with programmed intermittent epidural bolus administration.Between August and November 2021, 182 nulliparous and healthy women with singleton pregnancy, 2-5 cm cervical dilation, and requesting neuraxial analgesia were randomized to receive either single-orifice or multiorifice catheters. Epidural analgesia was initiated and maintained with 0.1% ropivacaine and 0.3 µg/mL sufentanil. Programmed intermittent epidural bolus volume of 10 mL was administered every 45 min at 480 mL/hour beginning immediately after the test dose. Primary outcome was the percentage of parturients in the two groups with adequate analgesia 20 min after the initial bolus.Compared with multiorifice catheters, single-orifice catheters were associated with a higher proportion of parturients with adequate analgesia (71.8% vs 56.0%, respectively; 95% CI 1.3% to 29%, p=0.03) and more frequent S2 sensory blockade (37.6% vs 22.6%, respectively; 95% CI -30% to 1%, p=0.03) 20 min after block initiation. Median time (IQR) to adequate analgesia was 12 (8-30) min and 20 (10-47) min with single-orifice and multiorifice catheters, respectively (95% CI 0.1 to 0.7 min, p<0.01). The median (IQR) ropivacaine consumption per hour was higher in parturients receiving multiorifice catheters than those with single-orifice catheters (15.3 (13.3-17.0) mg/hour vs 13.3 (13.3-15.4) mg/hour, respectively; 95% CI 0.2 to 0.8 mg/hour, p<0.001).Single-orifice catheters used for programmed intermittent epidural bolus at 480 mL/hour for epidural labor analgesia had improved analgesic efficacy than multiorifice catheters.ChiCTR2100049872.