Low-Dose Intranasal Dexmedetomidine Premedication Improves Epidural Labor Analgesia Onset and Reduces Procedural Distress on Epidural Puncture: A Prospective Randomized Double-blind Clinical Study

Abstract

Abstract Background Epidural labor analgesia is a safe and effective method of pain management during labor with the drawbacks of delayed onset and the maternal distress on the epidural puncture. This study aimed to determine whether pretreatment with intranasal low-dose dexmedetomidine (IND) effectively shortens the onset of analgesia and reduces procedural pain. Methods In this prospective randomized double-blind trial, nulliparous patients were randomly assigned to either the IND or the control group (CON). The IND group received 0.5 µg/kg dexmedetomidine intranasally, and the CON group received an equal volume of normal saline also intranasally. Two groups were maintained with a programmed intermittent epidural bolus (PIEB). The primary outcome was the onset time of analgesia and procedural pain scores caused by the epidural puncture. Results 79 patients were enrolled, 60 completed the study and were included in analysis. The time to adequate analgesia was significantly shorter in the IND group than that in the CON group (Hazard ratio=2.069; 95% CI, 2.187 to 3.606; P=0.010). The visual analogue scale (VAS) scores during epidural puncture in the IND group were also significantly lower than those in the CON group [2.0 (1.8-2.5) vs. 3.5 (3.3-4.5) , P≤0.001, Table2]. IND in combination with PIEB was associated with improved VAS and Ramsay scores, fewer consumption of analgesics and PCEA boluses, and higher maternal satisfaction (P<0.05). No differences were shown in labor and neonatal outcomes and incidence of adverse effects between the two groups. Conclusions IND yielded a faster onset of analgesia, and decreased epidural puncture pain without increasing adverse effects. Pretreatment with IND may be a useful adjunct on initiation of epidural analgesia, and further investigation should be encouraged to better determine its utility. Trial Registration: This trial was prospectively registered at Chictr.org.cn on 29/05/2020 with the registration number of ChiCTR2000033356 (http://www.chictr.org.cn/ listbycreater.aspx).