RESUMO
Objective To explore the effects and feasibility of minimal local analgesic dose of hyperbaric levobupivacaine in elderly patients undergoing unilateral spinal anesthesia during lower limb orthopedic surgery.Methods Seven hundred and fifty-six elderly patients who scheduled lower limb orthopedic surgery were assigned to levobupivacaine group (383 patients) and bupivacaine group (373 patients) by random digits table method.Haemodynamic change were monitored before,during and after anesthesia.The level and duration of sensory and motor block in each group were evaluated.Results Compared with bupivacaine group,the sensory block and motor block onset time was significantly longer in levobupivacaine group [(5.9 ± 1.4) min vs.(4.2 ± 0.3) min,(11.7 ± 3.0) min vs.(9.1 ± 3.3) min] (P ＜0.05),but the motor block duration was shorter [(152.8 ± 17.5) min vs.(195.4 ± 18.7) min] (P ＜ 0.05).The scores of maximum motor block in levobupivacaine group was significantly lower than that in bupivacaine group[(1.1 ±0.3) min vs.(2.3 ±0.6) min](P＜ 0.05).There was no significant difference in peak sensory block and haemodynamic between two groups (P ＞ 0.05).Conclusions Although levobupivacaine may be less potent than bupivacaine,it may be preferred for elderly patients with lower limb surgery because of satisfactory spinal anesthesia,good hsemodynamic stability and fast motor block regression.