等剂量不同浓度罗哌卡因用于臂丛神经阻滞效果及血药浓度观察

The effect and plasma concentration observation in intersclance brachial plexus block anesthesia with the same dosage different concentrations of ropivacaine

目的探讨罗哌卡因用于肌间沟臂丛神经阻滞效果与血药浓度的关系。方法择期行上肢骨科手术患者60例,随机均分为三组,罗哌卡因150 mg分别配成20 ml(0.75%,A组)、30 ml(0.5%,B组)和40 ml(0.375%,C组),神经刺激仪定位行肌间沟臂丛神经阻滞。观察感觉、运动阻滞情况;高效液相法测定注药后10、15、20、30、60、90、120 min静脉血罗哌卡因浓度。结果感觉和运动阻滞起效时间均为A组<B组<C组(P<0.05)。A、B组血药浓度均在注药后15 min达峰浓度,C组在注药后30 min达峰浓度。结论等剂量高浓度罗哌卡因肌间沟臂丛神经阻滞起效快,扩散范围小,血药浓度达峰时间早;低浓度起效慢,但扩散范围大,达峰时间晚。

Objective To observe the relation of volume, concentration, plasma level and clinical effect in the intersclance brachial plexus block anesthesia with the dosage of 150 mg ropivacaine. Methods Sixty ASA Ⅰ or Ⅱ patients undergoing upper limb surgery were randomly divided into 3 groups, group A and B and C separately receiving 20 ml（0.75%）, 30 ml（0. 5%）, 40 ml （0. 375%） ropivacaine 150 mg in interscalence brachial plexus block with nerves stimulator. The degree of sensory and motor block were observed by single blind method, the vital sign variations were recorded during anesthetic duration, the ropivacaine concentrations in venous blood were measured by HPLC method after injection 10, 15, 20, 30, 60, 90,120 min. Results The vital signs were stable and attained good anaesthesia effect in the three groups. Group A, B reached the peak concentration in the 15 min, while group C reached in the 30 rain, but the peak concentrations were still safety range, the overal absorption in group B was the slowest. Conclusion The onset time and reached the peak blood concentration time was quicker when the ropivacaine concentration increased in the intersclance brachial plexus block anesthesia with the dosage of 150 rag, the segments blocked were widened and the peak blood concentration reached time was slower when the volume increased.