腰麻联合硬膜外麻醉药物扩散机理的临床研究

Clinical study of the local anesthetic spreading mechanism during combined spinal and epidural anesthesia

目的初步探讨腰麻联合硬膜外麻醉时药物扩散的初始机制。方法 30例子宫切除术病人随机分为三组 :A组SA后 2 5分钟内硬膜外腔不注射任何药物 ;B组SA后 5分钟硬膜外腔注射2 %利多卡因 10ml;C组SA后 5分钟硬膜外注射生理盐水 10ml。每 5分钟测定一次感觉平面和下肢肌力 ,直至 2 5分钟 ,评判麻醉效果和辅助药用量。。结果B、C组在硬膜外注药 5分钟后平面上升迅速且较A组快 (P <0 0 5 ) ;B、C组间各时点平面及平面减退开始时间比较差异无显著意义 (P >0 0 5 ) ;下肢肌力分级 3组间比较差异无显著意义 (P >0 0 5 ) ;麻醉效果及辅助用药用量差异不显著。结论联合腰麻硬膜外麻醉药物扩散初始机理为容量效应。

Objective To study the mechanism of spreading of local anesthetics during combined spinal and epidural anesthesia. Methods 30 patients of elective uterectomy were randomly divided into three groups, subarachnoid anesthesia was established in all patients at L 2～3 , group A ( n =10) received no any treatment after spinal. Group B received epidural 2% lidocaine 10 ml and group C received epidural saline 10ml after the spinal injection at 5 min. The sensory level was tested by pinprick every 5 min; motor function in the lower limbs was assessed at 5 min intervals and graded according to the improved Bromage’s classification; assessed the quality of anesthesia and recorded the supplemented does of fentanil. Results The extension of the level of sensory block was found to be similar in group B and group C and significantly incresed faster than that the group A ( P <0.05) and had stabilized by 20 min. The degree of motor block was similar in the three groups. The quality of anesthesia and the used does of fentanil were similar for B, C groups. Conclusion The first spreading mechanism of local anesthetics during combined spinal and epidual anesthesia was a volume effect.