Safe dosage of intrathecal injection of sufentanil for preemptive analgesia in lower limb orthopaedic surgery

Abstract

Objective To selected the safe dosage of intrathecal injection of sufentanil for preemptive analgesia in lower limb orthopaedic surgery.Methods Selected 96 patients who ASA classification Ⅰ - Ⅱ grades undergoing elective lower limb orthopaedic surgery with subarachnoid epidural block down,they were divided into six groups by random number table and double blind method,each group of 16 cases.Group Ⅰ,Ⅱ,Ⅲ,Ⅳ,Ⅴ,Ⅵ received 0.05,0.10,0.15,0.20,0.25,0 μ g/kg of intrathecal sufentanil and 2.5 ml of 0.5％ levobupivacaine.Observed and recorded the duration of block level of pain to T10,visual analog score (VAS)postoperative at 2,4,6,8,12,24,48 h,and side effects.Results The duration of block level of pain to T10 of group Ⅰ,Ⅱ,Ⅲ,Ⅳ,Ⅴ,Ⅵ was (245.6 ± 34.2),(259.3 ± 36.7),(268.9 ± 37.8),(286.6 ± 38.8),(287.7 ± 39.1 ),(228.6 ± 31.4) min.There was no significant difference between group Ⅳ and group Ⅴ (P ＞ 0.05 ),the differences of other groups were statistically significant (P ＜ 0.05 ).Compared with group Ⅴ,VAS of group Ⅲ and group Ⅳ at 6,8,12,24,48 h after operation was not statistically significant (P ＞ 0.05),and they were lower than the other three groups (P ＜ 0.05 ).There were no respiratory depression occurred after operation in group Ⅰ,Ⅱ,Ⅲ,Ⅳ,Ⅵ,4 cases occurred in group Ⅴ.Conclusion The best of effective dose of intrathecal injection of sufentanil for preemptive analgesia in lower limb orthopaedic surgery is 0.20 μ g/kg. Key words: Injections,spinal; Sufentanil; Preemptive analgesia; Orthopaedic surgery