IngentaConnect Effects of volume and concentration of lidocaine on epidural anae...

Authors: Nakayama M.; Yamamoto J.; Ichinose H.; Yamamoto S.; Kanaya N.; Namiki A.

Source: European Journal of Anaesthesiology, Volume 19, Number 11, 1 November 2002 , pp. 808-811(4)

Abstract:

Background and objective: The effects of altering the concentration of a local anaesthetic on the development of epidural anaesthesia in pregnant females are unclear. We compared the anaesthetic effects of a constant dose of two different concentrations of epidural lidocaine for Caesarean section.

Methods: After Institutional Review Board approval and informed consent, patients undergoing elective Caesarean section were randomized to receive either lidocaine 1% 30 mL (+epinephrine 5 µg mL^-1) or lidocaine 2% 15 mL (+epinephrine 5 µg mL^-1) (n = 20 each) for epidural anaesthesia at the L1-L2 interspace. The spread of the sensory block to pinprick and the degree of motor block (modified Bromage scale) were measured at 5, 10, 15, 20 and 30 min after injection.

Results: No significant differences in the progression of analgesia and motor block were observed at any time between 1 and 2% lidocaine. The maximum cephalad spread was observed 30 min after injection; the median was at T₄ (range T₃-T₅) and at T₄ (range T₃-T₆) for lidocaine 1 and 2%, respectively.

Conclusions: The same doses but different volumes of lidocaine 1 and 2% produced comparable anaesthetic effects in pregnant females. The effects of epidural anaesthesia depend primarily on the total dose of the local anaesthetic.

Effects of volume and concentration of lidocaine on epidural anaesthesia in pregnant females