Epidural Neostigmine Combined with Sufentanil Provides Balanced and Selective Analgesia in Early Labor

Background This study evaluated the efficacy of an epidural single dose of neostigmine combined with sufentanil to provide selective and balanced analgesia at the beginning of labor. Methods After informed consent, 125 healthy parturients were randomly allocated to receive, after a test dose, a single injection of either epidural sufentanil 20 micrograms (minimal analgesic dose) or 10 micrograms or a combination of sufentanil 10 micrograms with neostigmine 250, 500, or 750 micrograms in a total volume of 12 ml. Pain scores were recorded at regular intervals to determine onset and duration of analgesia. Maternal and fetal vital parameters as well as side effects were closely monitored. Results Parturients did not differ concerning demographic data. Epidural neostigmine 500 micrograms with sufentanil 10 micrograms produced effective analgesia (visual analog scale <30 mm within 10 min in 72% parturients and within 15 min in 85% parturients; average duration of 119 min, confidence interval 96-142 min) that was as effective as epidural sufentanil 20 micrograms. Epidural combination with neostigmine 250 micrograms was ineffective, whereas 750 micrograms did not produce higher effect than 500 micrograms. No motor block was recorded. Maternal and fetal vital parameters remained stable during labor. Conclusions Epidural combination of neostigmine 500 micrograms (e.g., 6-7 micrograms/kg) with sufentanil 10 micrograms provides similar duration of analgesia as epidural sufentanil 20 micrograms and allows effective and selective analgesia devoid of side effects in the first stage of labor.