Chloroprocaine-bupivacaine sequence for obstetric extradural analgesia.

Two case reports, one a vaginal delivery, the other a Caesarean Section, have been presented to demonstrate the rationale of employing a chloroprocaine-bupivacaine sequence for extradural analgesia in obstetrics. Use of chloroprocaine for initiation and bupivacaine for maintenance of the block offers at least three advantages: (1) onset of pain relief is prompt while duration is prolonged; (2) more than one "test" dose of chloroprocaine may be employed with safety in rapid succession; (3) two drugs with different metabolic patterns are used, each in reduced amount.