Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2019 Apr;33(2):221-229.
doi: 10.1007/s00540-018-2601-x. Epub 2019 Jan 2.

Transcranial motor-evoked potentials of laryngeal muscles for intraoperative neuromonitoring of the vagus nerve during thyroid surgery

Takashi Ichino  1 , Satoshi Tanaka  2 , Ryusuke Tanaka  1 , Naruaki Tanaka  1 , Takashi Ishida  1 , Yuki Sugiyama  1 , Mikito Kawamata  1
Affiliations

Transcranial motor-evoked potentials of laryngeal muscles for intraoperative neuromonitoring of the vagus nerve during thyroid surgery

Takashi Ichino et al. J Anesth. 2019 Apr.

Abstract

Purpose: The aim of this study was to elucidate normative features of vagal motor-evoked potentials (MEPs) induced by transcranial electrical stimulation (TES) and to determine the influence of functional decline of the recurrent laryngeal nerve (RLN) on vagal MEPs during thyroid surgery.

Methods: A total of 54 patients undergoing elective thyroid surgery under general anesthesia were enrolled in this study. Vagal MEPs induced by TES were measured from the vocal cord using one of two types of electrodes (wire type or wide and flat type) mounted on an endotracheal tube. We investigated the effects of stimulation intensity and train pulse number on vagal MEP amplitude, the time course of vagal MEP amplitude during surgery, and the effects of functional decline of the RLN on vagal MEPs.

Results: The success rate of vagal MEP monitoring with wide- and flat-type electrodes was significantly higher than that with wire-type electrodes. Reliable vagal MEPs were obtained at a stimulation intensity of approximately 300 V with 3 or more pulses in 91% of the patients without preoperative RLN palsy (RLNP), and the amplitude was augmented with increasing stimulation intensity and train pulse number. Vagal MEP amplitude decreased during thyroid surgery and then partially recovered at the end of surgery. Vagal MEP amplitude recorded from the electrode ipsilateral to preoperative RLNP was significantly lower than that on the contralateral intact side.

Conclusion: Vagal MEPs induced by TES can be obtained with a high success rate during thyroid surgery and would reflect functional status of the RLN.

Keywords: Electromyographic endotracheal tube; Motor-evoked potential; Recurrent laryngeal nerve palsy; Transcranial electrical stimulation; Vagus nerve.

PubMed Disclaimer

Comment in

  • Transcranial MEP monitoring of vagus nerve.
    Yoo S, Kim WH, Kim JT. Yoo S, et al. J Anesth. 2019 Apr;33(2):346. doi: 10.1007/s00540-019-02618-4. Epub 2019 Mar 9. J Anesth. 2019. PMID: 30852683 No abstract available.
  • Reply to the letter to the editor.
    Tanaka S, Ichino T, Kawamata M. Tanaka S, et al. J Anesth. 2019 Apr;33(2):349. doi: 10.1007/s00540-019-02617-5. Epub 2019 Mar 9. J Anesth. 2019. PMID: 30852684 No abstract available.

Similar articles

See all similar articles

Cited by

References

    1. World J Surg. 2008 Sep;32(9):1935-9 - PubMed
    1. Langenbecks Arch Surg. 2004 Nov;389(6):499-503 - PubMed
    1. World J Surg. 2016 Aug;40(8):2051-8 - PubMed
    1. World J Surg. 2006 May;30(5):806-12 - PubMed
    1. ANZ J Surg. 2013 Jan;83(1-2):15-21 - PubMed

LinkOut - more resources