Pre-emptive analgesia with local anaesthetic for herniorrhaphy

There is little evidence that local anaesthetics produce pre-emptive analge sia and one reason may be the short duration of action of the drugs studied . We examined the pre-emptive analgesic effect of a bupivacaine field block on postoperative pain in 40 patients following herniorrhaphy in a double-b lind, randomised trial. Patients received the block either after induction but before surgery, or after surgery but before the end of anaesthesia. The re was no difference in pain scores or analgesic consumption up to 7 days a fter surgery between the two groups. We have demonstrated that bupivacaine does not appear to provide significant pre-emptive analgesia following a fi eld block for herniorrhaphy. This study does not support the hypothesis tha t pre-emptive analgesia with local anaesthetic depends upon the duration of action of the drug.