Comparison of single-versus double-injection techniques forsciatic nerve block / 中华麻醉学杂志

ABSTRACT

Objective To compare the single-and double-injection techniques for sciatic nerve block.Methods Sixty ASA physical status Ⅰ or Ⅱ patients of both sexes,aged 18-64 yr,weighing 48-72 kg,undergoing elective unilateral foot and ankle surgery,were randomly divided into 2 groups (n =30 each) using a random number tablesingle-injection group (group S) and double-injection group (group D).Labat-winnie approach to sciatic nerve block was performed under the guidance of a nerve stimulator.When ankle dorsal or plantar flexion developed,group S received a single injection of 0.5％ ropivacaine 30 ml.When ankle dorsal and plantar flexion developed,0.5％ ropivacaine 15 ml was injected each time in group D.The failure of location was recorded.The time spent performing the procedure,onset time and duration of sensory and motor blockade,and the total time for the block were recorded.The effectiveness of block (success,failure) was assessed.Results The failure rate of location was 10％ in group D.The success rate of block was 93％ in group S,and was 96％ in group D,and there was no significant difference in the success rate of block between the two groups.Compared with group S,the onset time of sensory and motor blockade was significantly shortened,the time spent performing the procedure was prolonged,and no significant change was found in the total time for the block,duration of sensory and motor blockade in group D.Conclusion Single-injection technique is recommended for the sciatic nerve block in the patients undergoing lower extremity surgery.