Shigihara A, Suzuki M, Tase C, Okuaki A, Kumada Y, Nozaki H
Department of Anesthesiology, Ohta Central Nishinouchi Hospital, Koriyama.
Masui. 1995 Jul;44(7):994-9.
The change of analgesic levels, plasma concentrations and the radiographical changes of epidural space due to continuous epidural block were studied in 54 patients receiving pain relief. All the patients received 2 ml per hour of 2% lidocaine or 0.5% bupivacaine via the catheter over two weeks. The effect of epidural block was determined on 1, 2, 4, 7, 10 and 14 days, the epidurogram was performed on 1, 7, 14 days, and plasma concentration of lidocaine or bupivacaine was measured on 1, 3, 7, 14 days. We removed catheters in 8 patients because of infection around the catheter, pain in the back during injection, the leakage of anesthetics, and spontaneous removal. The effects and plasma concentrations of epidural block decreased significantly after a week, and the mean segmental number of radiographic spread decreased significantly after two weeks. The decreasing effect or duration of epidural block was due to decrease in spread of anesthetics because of adhesion around the catheter in the epidural space. We conclude that the safety period of continuous epidural block is within 2 weeks.
对54例接受止痛治疗的患者研究了连续硬膜外阻滞引起的镇痛水平、血浆浓度变化以及硬膜外间隙的影像学改变。所有患者在两周内通过导管每小时接受2 ml 2%利多卡因或0.5%布比卡因。在第1、2、4、7、10和14天测定硬膜外阻滞效果，在第1、7、14天进行硬膜外造影，在第1、3、7、14天测量利多卡因或布比卡因的血浆浓度。因导管周围感染、注射时背部疼痛、麻醉药渗漏及自行拔除，我们拔除了8例患者的导管。一周后硬膜外阻滞效果和血浆浓度显著降低，两周后影像学扩散的平均节段数显著减少。硬膜外阻滞效果或持续时间的降低是由于硬膜外间隙导管周围粘连导致麻醉药扩散减少。我们得出结论，连续硬膜外阻滞的安全期在2周内。
