SPEED OF ONSET OF SENSORY BLOCK FOR ELECTIVE EXTRADURAL CESAREAN-SECTION - CHOICE OF AGENT AND TEMPERATURE OF INJECTATE

We have studied the effects of choice of local anaesthetic and tempera ture of extradural injectate on speed of onset of sensory block for el ective extradural Caesarean section in a double-blind trial in 120 wom en allocated randomly to one of four groups to receive either plain 0. 5% bupivacaine or 2% lignocaine with 1:200000 adrenaline at either roo m temperature or 38 degrees C. The onset time of lignocaine with adren aline was shorter than that of bupivacaine regardless of temperature ( P < 0.01). Warmed lignocaine produced the most rapid block overall (P < 0.025). The incidence of hypotension, ephedrine requirement, shiveri ng, quality of analgesia and additional analgesic requirements were si milar for all groups.