Analgesic Effects of Epidural Labor Analgesia at Different Periods and Its Effects on Maternal and Infant Outcomes and MiRNA-146b Level

This paper aimed to analyze the analgesic effects of continuous epidural labor analgesia (ELA) at different periods and its effects on postpartum depression, maternal and infant outcomes, and maternal blood pressure. Giving birth in our hospital from September 2017 to August 2019, 119 primiparas with spontaneous delivery were enrolled and divided into an observation group (65 cases) and a control group (54 cases). Patients in the observation group received epidural block analgesia in advance, whereas those in the control group received epidural block analgesia routinely. At 25 days after delivery, breast milk samples were collected, in which miRNA-146b level was detected by PCR. The patients were compared between the two groups with respect to progress of labor, analgesic effects during 3 stages of labor, labor outcomes, adverse reactions, and levels of NO, ANP, and ET-1 in the parturients’ umbilical artery blood. Compared with those in the control group, patients in the observation group had a remarkably higher miRNA-146b level in the breast milk ( P < 0.05 ), remarkably lower average Visual Analogue Scale (VAS) scores during the active phase and the second stage of labor ( P < 0.05 ), and remarkably higher levels of NO, ANP, and ET-1 ( P < 0.05 ). There were no statistically significant differences in adverse reactions and modes of delivery between the two groups ( P < 0.05 ). ELA starting from the latent phase can improve the miRNA-146b level in maternal breast milk, alleviate labor pain of parturients, and shorten stages of labor. Therefore, our study is worthy of clinical promotion. We still need to do more experiments and use more data to conclude more scientific results in future research work.

Circadian Variation in the Median Effective Dose of Epidural Ropivacaine for Labor Analgesia

Background: Labor pain perception has been demonstrated to exhibit a circadian rhythm with lower pain scores during the day compared with the night. This study aimed to determine and compare the median effective dose (ED50) of ropivacaine in parturients having epidural labor analgesia during the day vs. during the night.Methods: The study group consisted of 60 nulliparous healthy parturients who were assigned to one of two groups according to the time they requested labor analgesia: Day Group (7:01 am to 7:00 pm) and Night Group (7:01 pm to 7:00 am). A bolus of.15% ropivacaine was administered epidurally and effective analgesia was defined as the attainment of a visual analog scale (VAS) pain score ≤ 10 mm within 30 min. The dose of ropivacaine for the first parturient in each group was 18 mg. The dose for each subsequent parturient was varied with increments or decrements of 3 mg based on the response of the previous subject. The ED50 was calculated using up-down sequential analysis. Probit regression was used to estimate the relative mean potency of ropivacaine between groups.Results: The ED50 (mean [95% CI]) of ropivacaine was lower in the Day Group (17.9 [16.5–19.4] mg) than in the Night Group (20.9 [19.2–22.7] mg) (P = 0.003). The estimate of relative potency for ropivacaine for the Night Group vs. the Day Group was 0.85 (95% CI:0.56–0.98).Conclusions: Under the conditions of this study, the dose requirement for epidural ropivacaine for labor analgesia was ~ 15% greater during the night than during the day.Clinical Trials Registration: Chinese Clinical Trial Registry (No.: ChiCTR1900025269. http://www.chictr.org.cn/showprojen.aspx?proj=36993).

Anatomical dimensions of the lumbar dural sac predict the sensory block level of continuous epidural analgesia during labor

Background The anatomical dimensions of the lumbar dural sac determine the sensory block level of spinal anesthesia; however, whether they show the same predictive value during continuous epidural anesthesia (CEA) remains undetermined. We designed the present study to verify the efficacy of the anatomical dimensions of the lumbar dural sac in predicting the sensory block level during labor analgesia. Methods A total of 122 parturients with singleton pregnancies requesting labor analgesia were included in this study. The lumbar dural sac diameter (DSD), lumbar dural sac length (DSL), lumbar dural sac surface area (DSA), and lumbar dural sac volume (DSV) were measured with an ultrasound color Doppler diagnostic apparatus. CEA was performed at the L2-L3 interspace. After epidural cannulation, an electronic infusion pump containing 0.08% ropivacaine and sufentanil 0.4 μg/ml was connected. The sensory block level was determined with alcohol-soaked cotton, a cotton swab, and a pinprick. The analgesic efficacy of CEA was determined with a visual analog scale (VAS). The parturients were divided into two groups, “ideal analgesia” and “nonideal analgesia,” and the groups were compared by t test. Pearson’s correlation was performed to evaluate the association between the anatomical dimensions of the lumbar dural sac and sensory block level. Multiple linear regression analysis was used to create a model for predicting the sensory block level. Results In the ideal analgesia group, the height, DSL, DSA, DSV and DSD were significantly smaller, and the body mass index (BMI) was significantly larger (P < 0.05). In addition, the DSL demonstrated the strongest correlation with the peak level of pain block (r = − 0.816, P < 0.0001; Fig. 2A), temperature block (r = − 0.874, P < 0.0001; Fig. 3A) and tactile block (r = − 0.727, P < 0.0001; Fig. 4A). Finally, the multiple linear regression analysis revealed that DSL and BMI contributed to predicting the peak sensory block level. Conclusion In conclusion, our study shows that the sensory block level of CEA is higher when the DSL, DSA, DSV and DSD of puerperae are lower. DSL and BMI can be treated as predictors of the peak sensory block level in CEA during labor analgesia.