Comparison of epidural anaesthesia with ropivacaine 0.5% and bupivacaine 0.5% for caesarean section.

PURPOSE: To compare ropivacaine 0.5% with bupivacaine 0.5% for epidural anaesthesia for Caesarean section. METHODS: Healthy pregnant women, scheduled for elective Caesarean section were enrolled into this randomized, double-blind, parallel-group study. Epidural block was obtained with 20-30 ml of ropivacaine (group R) or bupivacaine (group B) and surgery started when anaesthesia was reached T6. Maternal heart rate and blood pressure and fetal heart rate were assessed before the test dose and at five minute intervals until the end of surgery. At the same intervals, sensory and motor block characteristics were determined. Apgar scores and Neurologic and Adaptive Capacity Scores (NACS) were determined after delivery. Adverse events were recorded. RESULTS: Sixty-five patients were enrolled and data from 61 were available for analysis; 30 ropivacaine and 31 bupivacaine. Time from the end of the last injection to the start of surgery was 46 +/- 13 min (mean +/- SD) in gp R and 53 +/- 25 min in gp B (P:NS). The median duration of analgesia varied between 1.7 and 4.2 hr in gp R and between 1.8 and 4.4 hr in gp B (P:NS). In patients who developed Bromage 4 block, it persisted longer in those in gp B (2.5 hr) than in gp R (0.9 hr) (P < 0.05). The quality of analgesia was satisfactory in 27/29 patients (93%) in gp R and 27/31 patients (87%) in gp B (P:NS), although supplemental i.v. opioid was required in ten and seven patients, respectively. The most common adverse events in the mother were hypotension (63% gp R and 61% in gp B) (NS) and nausea (30% and 58%, in group R and B, respectively) (P = 0.05). Apgar scores were 7 after five minutes in all neonates. CONCLUSION: Ropivacaine 0.5% and bupivacaine 0.5% provided effective epidural anaesthesia for Caesarean section although supplementation with i.v. opioid was commonly required.

Double-blind comparison of epidural ropivacaine 0.25% and bupivacaine 0.25%, for the relief of childbirth pain.

PURPOSE: To evaluate the efficacy of ropivacaine 0.25% when administered epidurally for relief of labour pain and to compare it with bupivacaine 0.25%. METHODS: In a multicentre investigation, 60 ASA I and II labouring women were randomized in a double-blind fashion to receive either bupivacaine 0.25% or ropivacaine 0.25% administered epidurally by intermittent top-up for labour analgesia. Using a standardized technique, epidural analgesia was initiated after the woman received 10-15 ml-kg.1 crystalloid solution. Maternal blood pressure, heart rate, analgesia sensory level, degree of motor block and visual analogue pain scores were measured by the research nurse prior to, and at regular intervals, following the administration of analgesia. Total dose of local anaesthetic administered, duration of labour, mode of delivery, and maternal and fetal/neonatal side effects were noted. The fetus/neonate was assessed by the research nurse using the fetal heart rate tracing, Apgar scores at delivery and neonatal neurobehavioural assessments at 2 and 24 hr postnatally. Maternal and investigators' satisfaction with the analgesia achieved was assessed after delivery. RESULTS: No differences were found between the two agents in any of the variables studied. CONCLUSION: Ropivacaine 0.25%, when administered epidurally by intermittent top-ups for labour analgesia, was equally efficacious as bupivacaine 0.25%.

The disposition of SK&F L-94901, a selective thyromimetic in rat, dog and cynomolgus monkey.

SK&F L-94901 is a novel thyromimetic, structurally related to thyroxine. The absorption, distribution, excretion and metabolism of radiochemically labelled [14C]-SK&F L-94901 has been investigated in the rat, dog and cynomolgus monkey. Oral absorption from solution was low or moderate in all three species. The compound was widely distributed and rapidly excreted, although traces of radioactivity were still evident in some tissues at 7 days post-dose, particularly in the kidney where radioactivity was located in an area approximating to the corticomedullary junction. Elimination of [14C]-SK&F L-94901 was both metabolic, mediated by the liver, and renal. The major metabolic routes of elimination were via oxidative deamination to lactate and acetate derivatives.