Schubert A, Licina M G, Lineberry P J, Deers M A
Department of General Anesthesiology, Cleveland Clinic Foundation, Ohio 44195-5154.
Anesthesiology. 1991 Sep;75(3):401-5. doi: 10.1097/00000542-199109000-00004.
Although the effect of systemic opioids on somatosensory evoked potentials has been well described, little is known about the interaction between intrathecally administered opioid analgesics and somatosensory evoked potentials. Accordingly, the influence of intrathecally administered morphine on posterior tibial nerve somatosensory cortical evoked potentials (PTSCEPs) was investigated in 22 unpremedicated, awake, neurologically normal patients scheduled to undergo elective abdominal or pelvic procedures. Patients were randomly assigned to receive either preservation-free intrathecal morphine sulfate (ITMS) or placebo. After baseline PTSCEP, heart rate and, mean blood pressure were recorded, ITMS (15 micrograms.kg-1) was injected via standard dural puncture with the patient in the lateral position. PTSCEPs, heart rate, and mean blood pressure were recorded again at 5, 10, 20, 30, 60, 90, and 120 min. Control patients were treated identically (including position, sterile preparation, and subcutaneous tissue infiltration with local anesthetic), except for lumbar puncture, and were unaware of their randomization. Before administration of ITMS, PTSCEP P1, N1, P2, N2, and P3 latencies were 39.4 +/- 3.2, 47.6 +/- 3.9, 59.2 +/- 3.2, 70.4 +/- 3.7, and 84.6 +/- 5.5 ms, (mean +/- standard deviation), respectively. The corresponding P1-N1, N1-P2, and P2-N2 amplitudes were 2.4 +/- 1.1, 2.4 +/- 1.1, and 2.3 +/- 0.9 microV, respectively. There were no significant changes over time between the control and ITMS groups. PTSCEPs resulting from left-sided stimulation were not different from those elicited by right-sided stimulation. All ITMS patients had intense postoperative analgesia for at least 24 h. It is concluded that ITMS does not affect PTSCEP waveforms in the 35-90 ms latency range during the awake state.(ABSTRACT TRUNCATED AT 250 WORDS)
尽管全身性阿片类药物对体感诱发电位的影响已有详尽描述，但关于鞘内注射阿片类镇痛药与体感诱发电位之间的相互作用却知之甚少。因此，本研究在22例计划接受择期腹部或盆腔手术、未用术前药、清醒且神经系统正常的患者中，探讨了鞘内注射吗啡对胫后神经体感皮层诱发电位（PTSCEPs）的影响。患者被随机分配接受无保留鞘内硫酸吗啡（ITMS）或安慰剂。在记录基线PTSCEP、心率和平均血压后，患者取侧卧位，通过标准硬膜穿刺注射ITMS（15微克/千克）。在5、10、20、30、60、90和120分钟时再次记录PTSCEPs、心率和平均血压。对照患者除不进行腰椎穿刺外，接受相同治疗（包括体位、无菌准备和局部麻醉剂皮下组织浸润），且不知道自己的随机分组情况。在注射ITMS前，PTSCEP的P1、N1、P2、N2和P3潜伏期分别为39.4±3.2、47.6±3.9、59.2±3.2、70.4±3.7和84.6±5.5毫秒（均值±标准差）。相应的P1-N1、N1-P2和P2-N2波幅分别为2.4±1.1、2.4±1.1和2.3±0.9微伏。对照组和ITMS组随时间均无显著变化。左侧刺激产生的PTSCEPs与右侧刺激诱发的无差异。所有ITMS患者术后均有至少24小时的强效镇痛。结论是，清醒状态下ITMS不影响35 - 90毫秒潜伏期范围内的PTSCEP波形。（摘要截选至250字）
