Chloroprocaine vs. bupivacaine for lumbar epidural analgesia for elective cesarean section.

The incidence and degree of hypotension, time to establish surgical analgesia, and several other maternal and fetal variables were studied when 2-chloroprocaine, 3 per cent, and bupivacaine, 0.5 per cent, were used for epidural analgesia in 30 women undergoing elective cesarean section. Surgical analgesia occurred 8 min sooner (P less than 0.001) with chloroprocaine (14 +/- 1 min) than with bupivacaine (22 +/- 2 min). Blood pressure values were significantly lower with chloroprocaine than with bupivacaine during the 18--to-32 min interval after local anesthetic injection, while pulse rates were higher (P less than 0.05) at 18, 20, and 22 min. Hypotension necessitating treatment with ephedrine occurred in 33 per cent of chloroprocaine-treated subjects, compared with 13 per cent of those receiving bupivacaine. Newborn outcome was excellent in both groups, as reflected by umbilical vessel blood-gas values, times to sustained respiration, and 5-min Apgar scores. The authors conclude that chloroprocaine disturbs maternal cardiovascular status more than does bupivacaine when used for cesarean section epidural analgesia. However, chloroprocaine can be employed safely in normal pregnancies if maternal hypotension is corrected rapidly.