Adrenaline, fentanyl or adrenaline and fentanyl as adjuncts to bupivacaine for extradural anaesthesia in elective caesarean section

Abstract

We have compared the effects of extradural fentanyl and fentanyl plus adrenaline with adrenaline alone as adjuncts to extradural bupivacaine in patients undergoing elective Caesarean section. Forty-five patients were allocated randomly to receive 0.45% bupivacaine 20 ml with adrenaline 4.5 μg ml-1, fentanyl 4.5 μg ml-1 or adrenaline plus fentanyl (4.5 μg ml-1 of each) as supplements. The main outcome measures were time to bilateral analgesia of T6 or higher, need for intraoperative analgesic supplements, observer rating of intraoperative analgesia and patient assessment of analgesia using a 10-cm visual analogue scale. The time to onset of analgesia to T6 was reduced insignificantly by the fentanyl solutions compared with adrenaline only. The quality of analgesia as assessed by the need for analgesic supplements was superior for the patients given fentanyl. An observer rating of pain and visual analogue pain scoring by the patient also indicated superior analgesia with fentanyl supplementation. Two patients experienced respiratory depression after extradural fentanyl and were given naloxone. Two neonates were also given naloxone. Close supervision is therefore recommended in the early postoperative period when this technique is used. © 1991 Copyright: 1991 British Journal of Anaesthesia.