Tsui B C, Gupta S, Finucane B
Department of Anaesthesia, University of Alberta Hospitals, Walter Mackenzie Health Sciences Centre, Edmonton, Canada.
Can J Anaesth. 1998 Jul;45(7):640-4. doi: 10.1007/BF03012093.
To examine the reliability of low current electrical epidural stimulation to confirm epidural catheter placement.
Forty patients with epidural catheters (19G Arrow Flextip plus) already in place for post-operative pain management were studied. An adapter (Arrow-Johans ECG Adapter) was attached to the connector of the epidural catheter. The epidural catheter and adapter were filled with normal saline. The cathode lead of the nerve stimulator was attached to the metal hub of the adapter. Catheter placement was judged to be correct or incorrect, depending upon the presence or absence of truncal or limb movement to 1 Hz stimulation (1-10 mA). A standard test dose (3 ml lidocaine 1.5% with 1:200,000 epinephrine) was then injected. The efficacy of the epidural morphine was assessed independently.
The sensitivity and specificity of the test was 100% and 91.6% compared with the standard test dose. The positive and negative predictive value was 96% and 100%. In predicting the clinical effect of epidural morphine, the sensitivity and specificity was 96.1% and 76.9%. The positive and negative predictive value was 89% and 90%. The correlation of unilateral or bilateral motor response from the test and sensory response from the lidocaine test with sensitivity and specificity was 91.6% and 53.0%. The predictive value for unilateral response was 61% and for bilateral was 88%.
This study establishes this test as a simple, objective and reliable technique for confirmation of epidural catheter placement.
探讨低电流电硬膜外刺激用于确认硬膜外导管位置的可靠性。
对40例已置入硬膜外导管（19G Arrow Flextip plus）用于术后疼痛管理的患者进行研究。将一个适配器（Arrow-Johans心电图适配器）连接到硬膜外导管的接头处。硬膜外导管和适配器中充满生理盐水。神经刺激器的阴极导线连接到适配器的金属接头。根据对1Hz刺激（1 - 10mA）时躯干或肢体运动的有无，判断导管位置正确与否。然后注射标准试验剂量（3ml 1.5%利多卡因加1:200,000肾上腺素）。独立评估硬膜外吗啡的疗效。
与标准试验剂量相比，该试验的敏感性和特异性分别为100%和91.6%。阳性预测值和阴性预测值分别为96%和100%。在预测硬膜外吗啡的临床效果时，敏感性和特异性分别为96.1%和76.9%。阳性预测值和阴性预测值分别为89%和90%。试验中的单侧或双侧运动反应与利多卡因试验中的感觉反应的敏感性和特异性的相关性分别为91.6%和53.0%。单侧反应的预测值为61%，双侧反应的预测值为88%。
本研究证实该试验是一种用于确认硬膜外导管位置的简单、客观且可靠的技术。
