Efficacy of ultrasound combined with nerve stimulator-guided suprapatellar anterior approach to sciatic nerve block in elderly patients undergoing knee arthroscopic surgery / 中华麻醉学杂志

ABSTRACT

Objective:To evaluate the efficacy of ultrasound combined with a nerve stimulator-guided suprapatellar anterior approach to sciatic nerve block in elderly patients undergoing knee arthroscopic surgery.Methods:Seventy American Society of Anesthesiology physical status Ⅱ or Ⅲ patients, aged>65 yr, scheduled for elective knee arthroscopic surgery, were divided into 2 groups ( n=35 each) using a random number table method: suprapatellar anterior approach group (S group) and traditional anterior approach group (T group). Puncture was performed under the guidance of ultrasound and a nerve stimulator in both groups.When dorsiflexion or plantar flexion was induced by stimulation of 0.3 mA current intensity, 0.25% ropivacaine plus 1% lidocaine (0.4 ml/kg) was injected.The success of puncture and block, depth of puncture, time to complete block, duration of block, insufficient analgesia, responses to tourniquet-induced discomfort, and block-related complications were recorded.The patients were followed up for 48 h after operation for the recovery time of foot dorsiflexion on the affected side. Results:Compared with T group, the success rate of puncture and block were significantly increased, the time to complete nerve block was shortened, the incidence of intraoperative insufficient analgesia was reduced ( P<0.05 or 0.01), and no significant change was found in the depth of puncture, duration of block, and recovery time of foot dorsiflexion on the affected side in S group ( P>0.05). No nerve block-related complications were found in the two groups. Conclusion:Ultrasound combined with a nerve stimulator-guided suprapatellar anterior approach to sciatic nerve block can provide satisfactory analgesia for elderly patients undergoing knee arthroscopic surgery with a higher safety.