Chitkara Ajay, Meyer Tanya, Cultrara Anthony, Blitzer Andrew
New York Center for Voice and Swallowing Disorders, New York, New York, USA.
Ann Otol Rhinol Laryngol. 2005 Nov;114(11):819-21. doi: 10.1177/000348940511401101.
Our purpose was to determine the effect of a dose response to decreasing concentrations of topical anesthetic upon laryngeal neuromuscular electrical transmission.
We performed a prospective study at a neurolaryngology referral center. Forty-three patients were divided into 5 groups. Each patient underwent laryngeal electromyography (EMG) of a thyroarytenoid muscle before and 60 seconds after topical laryngotracheal lidocaine hydrochloride, normal saline solution, or nothing was applied. The pretreatment and posttreatment measurements were recorded with the same indwelling EMG electrode. Group 1 (n = 12) received 4% lidocaine, group 2 (n = 9) received 2% lidocaine, and group 3 (n = 8) received 1% lidocaine. Group 4 (n = 5) received topical normal saline solution instead of lidocaine. A fifth group (group 5, n = 9) had 2 EMG recordings measured, each separated by 60 seconds, without topical anesthetic.
Groups 1, 2, and 3 showed significant decreases in the maximum peak-to-peak amplitude of the EMG recording (48.5%, 49.7%, 44.7%, respectively). Groups 4 and 5 failed to show a significant change in peak-to-peak amplitude after 60 seconds. There was no dose response change in EMG with decreasing lidocaine concentrations.
All concentrations of lidocaine administered in this study decreased the laryngeal neuromuscular electrical transmission as measured by laryngeal EMG. This group of patients did not exhibit any dose response to anesthetic concentration. This finding is clinically significant for both diagnostic and therapeutic uses of laryngeal EMG preceded by administration of topical anesthetic.
我们的目的是确定局部麻醉剂浓度降低的剂量反应对喉神经肌肉电传导的影响。
我们在一家神经喉科学转诊中心进行了一项前瞻性研究。43名患者被分为5组。每位患者在局部应用喉气管盐酸利多卡因、生理盐水溶液或不应用任何药物之前和之后60秒，接受甲杓肌的喉肌电图（EMG）检查。使用同一根留置的EMG电极记录治疗前和治疗后的测量值。第1组（n = 12）接受4%利多卡因，第2组（n = 9）接受2%利多卡因，第3组（n = 8）接受1%利多卡因。第4组（n = 5）接受局部生理盐水溶液而非利多卡因。第五组（第5组，n = 9）在不使用局部麻醉剂的情况下进行了两次EMG记录，每次记录间隔60秒。
第1、2和3组的EMG记录最大峰峰值幅度显著降低（分别为48.5%、49.7%、44.7%）。第4和5组在60秒后峰峰值幅度未显示出显著变化。随着利多卡因浓度降低，EMG未出现剂量反应变化。
本研究中给予的所有浓度的利多卡因均降低了通过喉EMG测量的喉神经肌肉电传导。这组患者对麻醉剂浓度未表现出任何剂量反应。这一发现对于在局部麻醉剂给药之前进行喉EMG的诊断和治疗用途具有临床意义。
