Low-dose clonidine infusion during labour

In this study, we have compared two different doses of clonidine (bolus of 25 micrograms and infusion of 19 micrograms h-1; bolus of 50 micrograms and infusion of 37 micrograms h-1, both added to 0.03% bupivacaine) with a control group of 0.03% bupivacaine alone. The study was performed in a randomized, double-blind manner, and a total of 45 patients were studied. Both clonidine regimens resulted in marked local anaesthetic sparing, with no change in the quality of analgesia. There was no difference in the severity of lower limb motor weakness and no difference in maternal sedation, although only a small number of patients were studied. No adverse maternal haemodynamic effects were observed. The newborn infants were not sedated on delivery. The number of fetal cardiotocographic traces judged to be of concern was higher in both clonidine groups. However, this just failed to reach statistical significance (P = 0.055).