Failure rate of epidural anaesthesia for foot and ankle surgery. A comparison with other surgical procedures.

To test whether epidural anaesthesia for foot and ankle surgery is associated with an unacceptably high incidence of inadequate surgical analgesia, we prospectively compared two groups of patients, one undergoing foot or ankle surgery (160 patients) and the other surgical procedures not performed in areas innervated by L5-S1 ( (168 patients). Lumbar epidural anaesthesia was performed in both groups by administering carbonated lignocaine 2\% with adrenaline 1:200000. Seven patients in the foot-ankle group (4.4\%) and 10 in the group for comparison (5.9\%) exhibited inadequate surgical analgesia. This difference is not statistically significant. Within the foot-ankle group, a significantly lower dose of local anaesthetic per spinal segment had been given to patients who displayed inadequate analgesia, compared with those who exhibited satisfactory analgesia (P < 0.05).