BACKGROUND: In labour analgesia, the combination of epidural clonidine and neostigmine as adjuvants to local anaesthetics and opioids is under investigation to provide a longer duration of initial spinal analgesia with local anaesthetics and/or opioids.
OBJECTIVES: To evaluate the quality of analgesia with epidural neostigmine and clonidine, added to initial spinal analgesia, and to test the hypothesis that the incidence of breakthrough pain could be reduced and patient satisfaction improved.
DESIGN: Randomised double-blind controlled trial.
SETTING: University Hospital of Leuven in Belgium.
PARTICIPANTS: One hundred healthy, term (≥37 weeks) parturients.
INTERVENTION: All patients received initial spinal analgesia with ropivacaine and sufentanil. Fifteen minutes after spinal injection, 10 ml of a solution containing neostigmine 500 μg and clonidine 75 μg, or 10 ml physiological saline alone was injected epidurally. Patient-controlled analgesia with ropivacaine and sufentanil was then made available.
MAIN OUTCOME MEASURES: The incidence of breakthrough pain, patient satisfaction and hourly ropivacaine use.
RESULTS: Ropivacaine use decreased significantly by 32.6% in the neostigmine/clonidine (NC) group [11.6 ± 4.2 vs. 17.2 ± 5.3 mg h−1 in the NC group and placebo (P) group, respectively] and a significant difference in breakthrough pain was noted; only 3% in group NC had breakthrough pain compared with 36% in group P. Patient satisfaction was better after 1 h in group NC compared with group P (P <0.05) but not different after 24 h (visual analogue scale score 97 ± 5 vs. 88 ± 11 mm after 1 h; 92 ± 10 vs. 90 ± 14 mm after 24 h).
CONCLUSION: The administration of epidural clonidine and neostigmine as adjuvants, following spinal injection of local anaesthetic, improves the quality of analgesia with less ropivacaine consumption, higher patient satisfaction 1 h after administration and a decrease in breakthrough pain compared to standard combined spinal and epidural analgesia and patient-controlled epidural analgesia with ropivacaine and sufentanil.