Impact of epidural labor analgesia using sufentanil combined with low-concentration ropivacaine on maternal and neonatal outcomes: a retrospective cohort study.

Whether epidural administered sufentanil combined with low-concentration ropivacaine affected labor progress as well as maternal and neonatal outcomes still remained unknown. The aim of this study was to assess the impact of epidural sufentanil plus ropivacaine on maternal and neonatal outcomes. This is a retrospective cohort study. Data of singleton full-term pregnancy women who received epidural labor analgesia for vaginal delivery from May 2018 to June 2020 were collected. Parturients were divided into two groups (the R group and the SR group) according to different medication regimens for epidural labor analgesia. The implementation of epidural analgesia during labor was performed with 0.167 % ropivacaine in the R group and 0.1 % ropivacaine in combination with 0.5 µg/ml sufentanil in the SR group. The primary outcome of our study included the duration of labor progress and the incidence of maternal fever, postpartum hemorrhage, fetal distress and neonatal Apgar scores less than 7 at 1 and 5 min. The secondary outcome included the incidence of episiotomy, instrumental delivery, caesarean section and grade III meconium-stained amniotic fluid. There were a total 3778 deliveries during the study period, 1994 and 1784 parturients were included in the R group and in the SR group, respectively. The length of the first stage of labor was remarkably shorter in the R group in comparison to the SR group (548.0 ± 273.0 vs. 570.9 ± 273.0, P = 0.013). No significant difference was found in the incidence of maternal fever, postpartum hemorrhage, fetal distress and in the neonatal Apgar scores less than 7 at 1 and 5 min between two groups. Other Maternal outcomes were comparable in the R group and the SR group. 0.5 µg/ml sufentanil plus 0.1 % ropivacaine for epidural labor analgesia prolonged the duration of the first stage of labor, but did not have additional impact on maternal and neonatal outcomes compared with the sole 0.167 % ropivacaine. Clinical Research Information Service with registration number ChiCTR2100045162 . Registered 7 April 2021.

Zhang L ，Xu C ，Li Y 《BMC Anesthesiology》

Effect of different concentrations of sufentanil combined with ropivacaine on epidural fever during labor: A single-center retrospective study.

Labor epidural analgesia (LEA) is associated with increased maternal body temperature; however, the responsible mechanism is unknown. Recent studies suggest that changes in EA affect the incidence of fever and that epidural sufentanil supplementation enhances analgesia and reduces the amount of local anesthetic. The aim of this study was to evaluate the effect of different concentrations of sufentanil combined with ropivacaine on intrapartum fever during delivery. We performed a retrospective study comparing maternal fever rates in patients receiving labor analgesia between December 2018 and January 2019. Each patient receiving different concentrations of sufentanil in their EA received either proposal H (0.08% ropivacaine + 0.4 µg/mL sufentanil) or proposal L (0.08% ropivacaine + 0.2 µg/mL sufentanil), with the same nulliparous status. The primary outcome of this study was the incidence of intrapartum maternal fever, which was defined as any temperature ≥ 38°C during labor using Fisher exact test. Secondary outcome measures included visual analog scale (VAS) pain scores, birth events, and neonatal outcomes. We observed a perinatal fever incidence rate of 11.7% in the group receiving proposal L, while the incidence rate was 19.8% in the group receiving proposal H (P = .001). Five hours after administration, the average body temperature of the puerpera decreased significantly in the proposal L group compared with proposal H group. In addition, treatment with 0.2 µg/mL sufentanil provided satisfactory pain relief during labor, shortened the first stage of labor and total labor time, reduced oxytocin use, and had no significant adverse effects on neonatal outcomes. EA may increase the risk of intrapartum epidural-associated fever. Compared with the 0.4 µg/mL sufentanil group, the 0.2 µg/mL sufentanil group can provide better analgesia and improve maternal fever. These retrospective results highlighted the importance of prospective and mechanistic studies of maternal fever associated with intraspinal analgesia.

Zhang S ，You Y ，Huang Y ，Lin C ，Lin Z ，Xue X ，Gao X ... -  《-》

Adjuvant Sufentanil Decreased the EC50 of Epidural Ropivacaine for Labor Analgesia in Healthy Term Pregnancy.

The optimal concentration of ropivacaine as epidural labor analgesia combined with sufentanil has not been established. This study aimed to determine the median effective concentration (EC50) of epidural ropivacaine for labor analgesia in healthy term pregnancy when co-administered with sufentanil as an adjuvant or alone. Sixty healthy parturients scheduled for epidural labor analgesia were enrolled in the study. They were divided into a saline group (Group C) and an epidural sufentanil (0.5 µg/mL) group (Group S). The initial concentration of ropivacaine was set at 0.125%, which was then varied by 0.01% using the up-and-down sequential allocation method. The hemodynamics were continuously monitored during delivery. A visual analog scale was used to evaluate the degree of pain. The Ramsay sedation score, duration of the labor stages, the onset of epidural analgesia, and adverse effects were recorded. Neonatal outcomes were evaluated using the Apgar scores and umbilical artery blood gas analysis. The EC50 of ropivacaine was 0.085% (95% CI, 0.079-0.090%) in Group S and 0.109% (95% CI, 0.105-0.112%) in Group C. The EC95 of ropivacaine was 0.096% (95% CI, 0.090-0.118%) in Group S, and 0.116% (95% CI, 0.113-0.127%) in Group C. The difference between the groups was statistically significant (p < 0.001). The stable hemodynamics, satisfactory analgesia, and good neonatal outcomes were comparable in both groups (P > 0.05). The EC50 of ropivacaine was reduced by 22% when co-administered with sufentanil for epidural labor analgesia in primipara. (www.chictr.org.cn; registration number: ChiCTR2000039547).

Xiang B ，Yang J ，Lei X ，Yu J ... -  《Drug Design Development and Therapy》

Programmed intermittent epidural bolus decreases the incidence of intra-partum fever for labor analgesia in primiparous women: a randomized controlled study.

Fan Y ，Hou W ，Feng S ，Mao P ，Wang X ，Jiang J ，Yuan H ，Shen X ，Feng S ，Li P ... -  《-》

Investigation of the Minimum Local Analgesic Concentration of Epidural Sufentanil Combined With Ropivacaine for Labor Analgesia.

Worldwide, there are only few studies focusing on labor analgesia on the MLAC (minimum local analgesic concentration) or EC50 (median effective concentration) of sufentanil and ropivacaine. Therefore, we determine the MLAC or EC50 of sufentanil and ropivacaine for epidural analgesia by using an up-down sequential allocation and survey its adverse effect in a prospective blinded randomized trial. Sixty nulliparous full-term parturients who required labor analgesia were recruited and randomly divided into the sufentanil and ropivacaine groups. The formulation was 25 μg sufentanil combined with 0.1% ropivacaine (added 0.9% normal saline to 75 ml). According to the response of a previous parturient, the dosage of sufentanil was increased or decreased by 5 μg in the sufetanil group; meanwhile, we also administrated an initial concentration of 0.1% ropivacaine combined with 22.5 μg sufentanil (added 0.9% normal saline to 75 ml) in the ropivacaine group. The concentration of ropivacaine was increased or decreased by 0.01% following the response of the previous parturient. The Brownlee up-down sequential allocation was used to estimate the MLAC of epidural ropivacaine and its 95% confidence intervals in labor analgesia. There were no significant changes for the two groups, including for age, height weight, active stage, second stage of labor, and gestational weeks (P = 0.769, 0.900, 0.603, 0.441, 0.577, and 0.695, respectively). The VAS scores of the parturient decreased to varying degrees (P < 0.0001) after labor analgesia compared with VAS before labor analgesia, and the most effective analgesia was reached in 60 min. The EC50 dose of epidural ropivacaine combined with 0.3 μg/mL sufentanil was 0.09687%, and the 95% CI was 0.08944%~0.1043%. Five parturients had PONV, and the incidence rate was 16.7%; one parturient had pruritus, so the incidence rate was 3.3%. The EC50 dose of epidural sulfetanil combined with 0.1% ropivacaine was 18.76 μg with a 95% confidence interval of 13.5-24.48 μg. There were no significant differences in the active stage, second stage of labor, and maternal and fetal hemodynamic data between the two groups. Notably, the Apgar scores for 1 min and 5 min were 10 scores for almost all of these patients. There were no significant differences between the two groups for maternal and fetal side effects, which had very low incidence rates. The MLAC of epidural sufentanil or ropivacaine could provide satisfactory and safe analgesia for parturients while having a low incidence rate of side effects.

Cai S ，Zheng J ，Meng Q ，Chai J ，Ma R ，Wang Y ，Zhang W ，Yang Z ... -  《-》