Epidural dexmedetomidine or esketamine versus fentanyl to decrease ropivacaine use for labor analgesia: A randomized...

Area of Science:

• Anesthesiology
• Obstetrics
• Pharmacology

Background:

• Nonopioid adjuvants in epidural anesthesia can decrease local anesthetic requirements.
• Patient-controlled epidural analgesia (PCEA) is a standard for labor pain management.

Purpose of the Study:

• To test if dexmedetomidine or esketamine, as epidural adjuvants with ropivacaine, could match fentanyl's efficacy in reducing hourly local anesthetic consumption during labor.
• To evaluate the non-inferiority of dexmedetomidine and esketamine compared to fentanyl for PCEA in laboring nulliparous women.

Main Methods:

• 120 laboring nulliparous women were randomized to receive PCEA with 0.075% ropivacaine plus fentanyl, dexmedetomidine, or esketamine.
• The primary outcome was hourly ropivacaine consumption, with a 20% difference considered clinically significant for non-inferiority testing.
• Adjuvant concentrations were 0.4 μg/mL fentanyl, 0.4 μg/mL dexmedetomidine, and 1.0 mg/mL esketamine.

Main Results:

• Hourly ropivacaine consumption was 12.4 mL/h (fentanyl group) and 11.9 mL/h (dexmedetomidine group), confirming non-inferiority (risk difference 0.5, 95% CI -1.0 to 2.0).
• Hourly ropivacaine consumption was 14.3 mL/h in the esketamine group, failing to meet non-inferiority criteria compared to fentanyl (risk difference 1.9, 95% CI 0.2 to 3.6).
• Pruritus was most common in the fentanyl group, while mild dizziness was highest in the esketamine group.

Conclusions:

• Epidural dexmedetomidine is non-inferior to fentanyl as an adjuvant for PCEA during labor.
• Epidural esketamine did not prove to be non-inferior to fentanyl for labor analgesia in this study.
• These findings suggest dexmedetomidine as a viable alternative adjuvant for labor epidural analgesia.