Comparison of 0.125% bupivacaine and 0.2% ropivacaine in obstetric analgesia

This comparative study of low doses of ropivacaine was conducted in order to identify the most effective form of analgesia during labour with the aid of supplementary low doses of fentanyl and clonidine. 60 ASA I and II parturient primipares who had asked for epidural analgesia were randomly assigned to two groups. Group R was given 5-7 ml 0.2% ropivacaine and Group B 0.125% bupivacaine with both groups receiving 75 ng clonidine and 50 ng fentanyl with their first bolus of local anaesthetic. The parameters measured included the speed and spread of the sensory blockade and the scale of any motor blockade. The material haemodynamics and VAS pain relief scores were also measured at 30-minute intervals during labour and all side-effects (nausea, vomiting, localised or generalised itching, headache etc) were also monitored. Apgar anaesthetics and other drugs was decided on the basis of the VAS score (a further dose was given to women with a VAS of > 3-4). The study was completed by a telephone interview 6 months after delivery and the data were analysed using the Student's t-test and the chi 2 test. The analgesic effect was satisfactory in both groups and no statistically significant differences were found between the two groups under most of the headings analysed, apart from the top-up doses needed to maintain adequate analgesia. The average time between the first VAS to parturition was 292 mns in Group B and 267 mns in Groups R. Top-up doses of local anaesthetic (2.35 vs 5.05) came on average to 15.8 ml in Group B compared to 24.1 ml in Group R. There were 20% Caesarian sections in Group R and 13.8% in Group B. Optimum analgesia was achieved in Group R, the level of analgesia was insufficient or barely sufficient in 3.3% of cases. There was no Apgar score < 7 in either group. It was therefore concluded that both bupivacaine and ropivacaine offer excellent analgesia during labour and have no significant side effects on mothers or babies.