Combination of dexmedetomidine and remifentanil for labor analgesia: A double-blinded, randomized, controlled study

Application of Dexmedetomidine in Epidural Labor Analgesia: A Systematic Review and Meta-Analysis on Randomized Controlled Trials

OBJECTIVES

To summarize and appraise the use of dexmedetomidine in epidural labor analgesia, we conducted a systematic review and meta-analysis of randomized controlled trials (RCTs).

METHODS

We conducted the literature search about the RCTs of epidural labor analgesia with or without dexmedetomidine from inception until November 1, 2022, in the following databases: PubMed, Cochrane Library, and Embase. The primary outcome was visual analog scale (VAS) within 2 hours after epidural intubation. The secondary outcomes included the duration of the first and second labor stages, Apgar score, umbilical blood pH, dosage of analgesics, and side effects.

RESULTS

Eight RCTs including 846 parturients were included. The VAS score of the dexmedetomidine group was significantly lower than that of the control group at the time of 15 minutes (mean difference [MD] -1.41, 95% confidence interval [CI] -2.23, -0.59), 30 minutes (MD -1.02, 95% CI -1.70, -0.33), 60 minutes (MD -0.90, 95% CI -1.36, -0.44), and 90 minutes (MD -0.70, 95% CI -1.16, -0.23). The incidence of pruritus in the dexmedetomidine group was lower than that of the control group （MD 0.28, 95% CI 0.11, 0.74), but the incidence of maternal bradycardia was higher (MD 6.41, 95% CI 1.64, 25.04). There were no significant difference in other outcomes.

DISCUSSION

Dexmedetomidine combined with local anesthetic for epidural labor analgesia can improve the VAS score of parturients. Except for the increased incidence of maternal bradycardia, it seems to be safe for the parturients and fetuses.

Opioid-Free Labor Analgesia: Dexmedetomidine as an Adjuvant Combined with Ropivacaine

Background

Side effects of the use of opioid analgesics during painless delivery are the main factors that affect rapid postpartum recovery. Opioid use can result in dangerous respiratory depression in the patient. Opioids can also disrupt the baby's breathing and heart rate. The nonopioid analgesic dexmedetomidine, a new a2-adrenergic agonist, possesses higher selectivity, greater analgesic effects, and fewer side effects. Moreover, epidural administration of dexmedetomidine also reduces local anesthetic consumption.

Objective

Our study aims to compare the analgesic effects as well as the side effects of ropivacaine with dexmedetomidine against sufentanyl as an epidural labor analgesia.

Methods

This study is a randomized, double-blinded, controlled trial (registration no. ChiCTR2200055360) involving 120 primiparous (a woman who has given birth once), singleton pregnancy women who are greater than 38 weeks into gestation and have requested epidural labor analgesia. The participants were randomized to receive 0.1% ropivacaine with sufentanyl (0.4 μg/ml) or dexmedetomidine (0.4 μg/ml). The primary outcomes included Visual Analogue Score (VAS), duration of first epidural infusions, the requirement of additional PCEA bolus, and adverse reactions during labor analgesia.

Results

Of the 120 subjects who consented, 91 parturient women (women in the condition of labor) had complete data for analysis. Demographics and VAS, as well as maternal and fetal outcomes, were similar between the groups. The duration of first epidural infusions in dexmedetomidine was significantly longer than sufentanyl (median value: 115 vs 68 min, P < 0.01); the parturient women who received dexmedetomidine and who required additional PCEA bolus were fewer in comparison to those who received sufentanyl (27.5% vs 49.0%, P < 0.05). Furthermore, the incidence of pruritus in the dexmedetomidine group was lower in comparison to the sufentanyl group (0% vs 11.8%, P < 0.05).

Conclusions

Dexmedetomidine, a nonopioid, is superior to the opioid analgesic sufentanyl in providing a prolonged analgesic effect as an epidural during labor. It also reduces local anesthetic consumption and has fewer side effects. The trial is registered with ChiCTR2200055360.

Intravenous Dexmedetomidine as an Adjunct to Neuraxial Anesthesia in Cesarean Delivery: A Retrospective Chart Review

Background

Dexmedetomidine is a selective α-2 agonist commonly used for sedation that has been used in obstetric anesthesia for multimodal labor analgesia, postcesarean delivery analgesia, and perioperative shivering. This study evaluated the role of intravenous dexmedetomidine to provide rescue analgesia and/or sedation during cesarean delivery under neuraxial anesthesia.

Methods

We conducted a single-center, retrospective cohort study of all parturients undergoing cesarean delivery under neuraxial anesthesia between December 1, 2018, and November 30, 2019, who required supplemental analgesia during the procedure. Patients were divided into two groups: patients who received intravenous dexmedetomidine (Dexmed group) and patients who received adjunct medications such as fentanyl, midazolam, ketamine, and nitrous oxide (Standard group). Primary outcome was incidence of conversion to general anesthesia.

Results

During the study period, 107 patients received adjunct medications. There was no difference in conversion to general anesthesia between the Dexmed group and the Standard group (6% (4/62) vs. 9% (4/45); p=0.718). In the Dexmed group, the mean dexmedetomidine dose received was 37 μg (range 10 to 140 μg). While the use of inotropic/vasopressor medications was common and similar in both groups, there was an increase in the incidence of bradycardia (Dexmed 15% vs. Standard 2%; p=0.042) but not hypotension (Dexmed 24% vs. Standard 24%; p=1.00) in the Dexmed group.

Conclusion

In patients who required supplemental analgesia for cesarean delivery, those who received dexmedetomidine versus other medications had a similar rate of conversion to general anesthesia, a statistically significant increase in bradycardia, but no difference in the incidence of hypotension.

Effect of Epidural Dexmedetomidine as an Adjuvant to Local Anesthetics for Labor Analgesia: A Meta-Analysis of Randomized Controlled Trials

Background

This study aims to determine the analgesic effect and safety of dexmedetomidine as an adjuvant to epidural local anesthetics during labor.

Methods

Randomized controlled trials comparing epidural blocks with or without dexmedetomidine for labor analgesia were comprehensively searched. Review manager 5.4 was used to analyze the extracted data.

Results

Compared with placebo and opioids, dexmedetomidine relieved labor pain of 15 min (P=0.002), 30 min (P=0.01), and 120 min (P=0.02) after block and at the moment of fetal disengagement (P=0.0002), decreased mean arterial pressure of 120 min (P=0.01), heart rate of 30 min (P=0.003), 60 min (P < 0.00001), and 120 min (P < 0.00001) after block, blood loss (P=0.02), and the incidence of nausea/vomiting (P=0.006), and increased the incidence of maternal bradycardia (P=0.04). However, sensitivity analysis only found that the incidence of nausea/vomiting was significantly different. Compared with placebo, dexmedetomidine relieved labor pain of 30 min after block (P < 0.00001) and did not increase the incidences of side effects, but only two studies were enrolled. Compared with opioids, dexmedetomidine decreased the incidence of nausea/vomiting (P=0.002), increased the incidence of maternal bradycardia (P=0.04), and had a similar effect on labor pain relief; however, sensitivity analysis found that significant difference existed only at the incidence of nausea/vomiting. Other outcomes from meta-analysis or subgroup analysis were not different.

Conclusions

Epidural dexmedetomidine has the potential to offer a better analgesic effect than placebo, similar labor pain control to opioids, and has no definite adverse effects on the parturient or fetus, but more high-quality studies are needed to confirm these conclusions.

Comparison of ropivacaine plus sufentanil and ropivacaine plus dexmedetomidine for labor epidural analgesia: A randomized controlled trial protocol

OBJECTIVE

Effective analgesia during delivery can not only decrease pain, but also have a significant function in ensuring the safety of baby and mother. Sufentanil is generally used opioid with ropivacaine in epidural anesthesia in labor pain management; however it can cause some adverse reaction. Dexmedetomidine is an a2-adrenoceptor agonist with high selectivity. It possesses opioid-sparing and analgesic effects and it is suitable for the long-term and short-term intraoperative sedation. The purpose of this present study is to compare the analgesic effect of ropivacaine with dexmedetomidine against ropivacaine with sufentanyl in epidural labor.

METHODS

This is a single center, placebo-controlled randomized trial which will be performed from May 2020 to May 2021. It was authorized via the Institutional Review Committee in the first medical center of Chinese PLA General Hospital (S2018-211-0). One hundred sixty full-term protozoa are included in this work. They are randomly divided into four groups (n = 40 per group): the RD1 group (with the epidural administration of 0.125% ropivacaine + dexmedetomidine of 0.5 μg/mL), and the RD2 group (with the epidural administration of 0.08% ropivacaine + dexmedetomidine 0.5 μg/mL), the RS1 group (with the epidural administration of 0.125% ropivacaine + sufentanil of 0.5 μg/mL), as well as RS2 group (with the epidural administration of 0.08% ropivacaine + sufentanil of 0.5 μg/mL). Clinical outcomes are pain score, a modified Bromage scale, the Ramsay Sedation Scale, and adverse reactions during analgesia. All the needed analyses are implemented through utilizing SPSS for Windows Version 20.0.

RESULTS

The first table shows the clinical outcomes between these four groups.

CONCLUSION

This current work can provide a primary evidence regarding the clinical outcomes of dexmedetomidine versus sufentanil for labor epidural analgesia.

TRIAL REGISTRATION

This study protocol was registered in Research Registry (researchregistry5877).

A comparison of fetomaternal outcome in PCEA using fentanyl, clonidine and dexmedetomidine as adjuvants with Ropivacaine in painless labor: a prospective, double blinded randomized study

Background: Patient controlled epidural analgesia has been associated with marked maternal satisfaction. Combination of local anesthetics with various adjuvants have been tried to ensure optimum analgesia with no or negligible fetomaternal side effects. Aim: To compare fentanyl, clonidine or dexmedetomidine as adjuvants with ropivacaine for labor epidural analgesia (LEA) using a PCEA pump with the objective to assess fetomaternal outcome in terms of analgesic effect, success rate of vaginal delivery, complications, neonatal APGAR score and maternal satisfaction. Materials and methods: Sixty full term laboring women received 10 ml 0.2% ropivacaine followed by continuous infusion of 0.1% ropivacaine with 2 μg/ml of either dexmedetomidine, fentanyl or clonidine respectively in Groups A, B, and C at 6 ml/hr. demand bolus setting was 2 ml with a lock out interval of 15 minutes. At full cervical dilatation another 10 ml bolus of respective solution were given. Parturients were monitored at 0, 10, 20, 30 min after giving 1st epidural bolus dose and then at 30 min interval for ongoing labor for pain relief (VAS), motor blockade (Bromage score), progress of labor (duration of 1st stage and 2nd stage), mode of delivery, fetal APGAR score (at 1 min and 5 min), vitals (HR, NIBP, RR, SpO2), overall patient satisfaction and complications. The statistical analysis was done both qualitatively (Fisher-exact test/Chi-square test) and quantitatively (one-way analysis of variance test with post-hoc intergroup comparisons using Bonferroni’s correction). Results: Onset of pain relief was earlier in fentanyl group, however after 1 h all three groups showed comparable pain relief (P>0.05). There was a significant reduction in HR in group C and B compared to group A (P<0.001) and MAP in group C compared to groups A and B. The motor- blocking potency was slightly higher in dexmedetomidine group, however no significant motor weakness observed in any parturient. Mean demand bolus need was more in group C compared to A and B (P<0.001). There was no significant difference in mode of delivery (either SVD or cesarean) in between the groups. There was not a single case of fetal distress and most of the parturients showed satisfactory response to PCEA. Conclusion: All three study drugs produced equipotent analgesia in combination with ropivacaine 0.1%. There was absolute pain relief without significant motor blockade or any increase in instrumentation/cesarean deliveries or any adverse fetal outcomes.

Comparison of Dexmedetomidine and Fentanyl as an Adjuvant to Lidocaine 5% for Spinal Anesthesia in Women Candidate for Elective Caesarean

AIM

This study aimed to compare the effect of Dexmedetomidine and fentanyl as an adjuvant to lidocaine 5% in spinal anaesthesia to increase post-operative analgesia among women candidates for elective caesarean.

METHODS

Eighty-four pregnant women candidates for caesarian were randomly divided into fentanyl and Dexmedetomidine groups. In the first group, 25 μg fentanyl was added to lidocaine 5% while in the second group, 0.5 μg per kilogram Dexmedetomidine was added to lidocaine 5%. After the operation, a pain score of the patients in recovery and within 4, 12 and 24 hours after the operation, the average length of analgesia and the average amount of the analgesics taken within 24 hours and after the operation were recorded.

RESULTS

The average length of postoperative anaesthesia and the average amount of the drug taken within the first 24 hours after the operation in fentanyl group was more than the Dexmedetomidine group (P = 0.01). Shivering in Dexmedetomidine group was more common than what was observed in the fentanyl group (P = 0.001). Higher rates of nausea-vomiting were observed in the fentanyl group (P = 0.001).

CONCLUSIONS

Fentanyl results in a longer period of postoperative analgesia and less consumption of drugs after the operation. Fentanyl is recommended in caesarian.

Dexmedetomidine Added to Sufentanil Patient-Controlled Intravenous Analgesia Relieves the Postoperative Pain after Cesarean Delivery: A Prospective Randomized Controlled Multicenter Study

This study evaluated the efficacy and safety of dexmedetomidine in intravenous patient-controlled analgesia (PCA) after cesarean delivery. This multicenter study enrolled 208 subjects who were scheduled for selective cesarean delivery from 9 research centers. Patients received 0.5 ug/kg dexmedetomidine (study group) or normal saline (control group) after delivery and an intravenous PCA pump after surgery (100 μg sufentanil +300 μg dexmedetomidine for the study group, 100 μg sufentanil for the control group, background infusion: 1 ml/h, bolus dose: 2 ml and lock time: 8 min). The sufentanil consumption, pain scores, rescue analgesia, sedation scores, analgesic satisfaction, the incidence of postoperative nausea and vomiting (PONV) and the first passage of flatus were recorded within 24 h after surgery. The sufentanil consumption in the study group was significantly lower than that in the control group (p = 0.004). Compared with the control group, the study group had lower pain scores (p < 0.01), higher analgesic satisfaction degree [p < 0.001, odd ratio 4.28 and 95% CI (2.46, 7.46)], less requirement of rescue analgesia (p = 0.003), lower incidence of PONV (p = 0.005 and p < 0.001, respectively), and shorter time to first passage of flatus (p = 0.007). Dexmedetomidine added to sufentanil intravenous PCA significantly enhanced the analgesic effects, improved analgesic satisfaction, and had the potential benefits of reducing PONV and the recovery of intestinal functions after cesarean section.

Effect of Epidural Dexmedetomidine Combined With Ropivacaine in Labor Analgesia: A Randomized Double-Blinded Controlled Study

BACKGROUND

The purpose of our study is to evaluate the effect of adding dexmedetomidine to epidural ropivacaine in patients undergoing labor epidural analgesia.

METHODS

Eighty healthy women were randomly assigned to 2 groups: control group (R; n=40) received epidural 0.125% ropivacaine for labor analgesia, whereas the study group (D; n=40) received epidural 0.125% ropivacaine with dexmedetomidine in addition. The blood pressure, heart rate, and the severity of pain of the parturient was assessed, the duration of the first stage and the second stage of labor time, the rate of instrumental delivery and the rate of cesarean section were recorded. The side effects (nausea and vomiting), intensity of maternal sedation, and neonatal Apgar scores were also recorded.

RESULTS

The visual analog scales, systolic blood pressure, diastolic blood pressure, and heart rates of D group were significant lower than that of R group at most time intervals after epidural analgesia. The duration of the first and second stage of labor, the rate of instrumental delivery and cesarean section, neonatal 1- and 5-minute Apgar scores, umbilical artery pH, maternal motor blockade scores, intensity of maternal sedation, and the incidence of maternal complications did not show significant difference between 2 groups.

CONCLUSIONS

Low concentration of epidural ropivacaine (0.125%) combined with dexmedetomidine (0.5 μg/kg) reduces the feeling of pain, and does not show the problems of motor blockage, hemodynamic instability, extension of production process, and complications such as nausea and vomiting. Our study was registered with Chinese Clinical Trial Registry (ChiCTR-IOR-15007263).

Patient-controlled analgesia with remifentanil versus alternative parenteral methods for pain management in labour

BACKGROUND

Multiple analgesic strategies for pain relief during labour are available. Recently remifentanil, a short-acting opioid, has recently been used as an alternative analgesic due to its unique pharmacological properties.

OBJECTIVES

To systematically assess the effectiveness of remifentanil intravenous patient-controlled analgesia (PCA) for labour pain, along with any potential harms to the mother and the newborn.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (9 December 2015), ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform (ICTRP), handsearched congress abstracts (November 2015), and reference lists of retrieved studies.

SELECTION CRITERIA

Randomised controlled trials (RCTs) and cluster-randomised trials comparing remifentanil (PCA) with another opioid (intravenous (IV)/intramuscular (IM)), or with another opioid (PCA), or with epidural analgesia, or with remifentanil (continuous IV), or with remifentanil (PCA, different regimen), or with inhalational analgesia, or with placebo/no treatment in all women in labour including high-risk groups with planned vaginal delivery.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion, extracted data, and appraised study quality.We contacted study authors for additional information other than incomplete outcome data. We performed random-effects meta-analysis.To reduce the risk of random error in meta-analysis we performed trial sequential analysis. We included total zero event trials and used a constant continuity correction of 0.01 (ccc 0.01) for meta-analysis. We applied the Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) approach to assess the quality of evidence.

MAIN RESULTS

Twenty RCTs with 3569 women were included. Of those, 10 trials (2983 participants) compared remifentanil (PCA) to an epidural, four trials (216 participants) to another opioid (IV/IM), three trials (215 participants) to another opioid (PCA), two trials (135 participants) to remifentanil (continuous IV), and one trial (20 participants) to remifentanil (PCA, different regimen). No trials were identified for the remaining comparisons.Methodological quality of studies was moderate to poor. We assessed risk of bias as high for blinding issues and incomplete outcome data in 65% and 45% of the included studies, respectively.There is evidence of effect that women in the remifentanil (PCA) group were more satisfied with pain relief than women in the other opioids (IV/IM) group (standardised mean difference (SMD) 2.11, 95% confidence interval (CI) 0.72 to 3.49, four trials, very low-quality evidence), and that women were less satisfied compared to women in the epidural group (SMD -0.22, 95% CI -0.40 to -0.04, seven trials, very low-quality evidence).There is evidence of effect that remifentanil (PCA) provided stronger pain relief at one hour than other opioids administered IV/IM (SMD -1.58, 95% CI -2.69 to -0.48, three trials, very low-quality evidence) or via PCA (SMD -0.51, 95% CI -1.01 to -0.00, three trials, very low-quality evidence). Pain intensity was higher in the remifentanil (PCA) group compared to the epidural group (SMD 0.57, 95% CI 0.31 to 0.84, six trials, low-quality evidence).Data were limited on safety aspects for both the women and the newborns. Only one study analysed maternal apnoea in a comparison of remifentanil (PCA) versus epidural and reported that half of the women in the remifentanil and none in the epidural group had an apnoea (very low-quality evidence). There is no evidence of effect that remifentanil (PCA) was associated with an increased risk for maternal respiratory depression when compared to epidural analgesia (RR 0.91, 95% CI 0.51 to 1.62, ccc 0.01, three trials, low-quality evidence) and no reliable conclusion might be reached compared to remifentanil (continuous IV) (all study arms included zero events, two trials, low-quality evidence). In one trial of remifentanil (PCA) versus another opioid (IM) three out of 18 women in the remifentanil and none out of 18 in the control group had a respiratory depression (very low-quality evidence).There is no evidence of effect that remifentanil (PCA) was associated with an increased risk for newborns with Apgar scores less than seven at five minutes compared to epidural analgesia (RR 1.26, 95% CI 0.62 to 2.57, ccc 0.01, five trials, low-quality evidence) and no reliable conclusion might be reached compared to another opioid (IV) and compared to remifentanil (PCA, different regimen) both with zero events in all study arms (one trial, very-low quality evidence). In one trial of remifentanil (PCA) versus another opioid (PCA) none out of nine newborns in the remifentanil and three out of eight in the opioid (PCA) group had Apgar scores less than seven (very-low quality evidence).There is evidence that remifentanil (PCA) was associated with a lower risk for the requirement of additional analgesia when compared to other opioids (IV/IM) (RR 0.57, 95% CI 0.40 to 0.81, three trials, moderate-quality evidence) and that it was associated with a higher risk compared to epidural analgesia (RR 9.27, 95% CI 3.73 to 23.03, ccc 0.01, six trials, moderate-quality evidence). There is no evidence of effect that remifentanil (PCA) reduced the requirement for additional analgesia compared to other opioids (PCA) (RR 0.76, 95% CI 0.45 to 1.28, three trials, low-quality evidence).There is evidence that there was no difference in the risk for caesarean delivery between remifentanil (PCA) and other opioids (IV/IM) (RR 0.63, 95% CI 0.30 to 1.32, ccc 0.01, four trials, low-quality evidence) and epidural analgesia (RR 1.0, 95% CI 0.82 to 1.22, ccc 0.01, nine trials, moderate-quality evidence), respectively. Pooled meta-analysis revealed an increased risk for caesarean section under remifentanil (PCA) compared to other opioids (PCA) (RR 2.78, 95% CI 0.99 to 7.82, two trials, very low-quality evidence). However, a wide range of clinically relevant and non-relevant treatment effects is compatible with this result.

AUTHORS' CONCLUSIONS

Based on the current systematic review, there is mostly low-quality evidence to inform practice and future research may significantly alter the current situation. The quality of evidence is mainly limited by poor quality of the studies, inconsistency, and imprecision. More research is needed on maternal and neonatal safety outcomes (maternal apnoea and respiratory depression, Apgar score) and on the optimal mode and regimen of remifentanil administration to provide highest efficacy with reasonable adverse effects for mothers and their newborns.