title: Impact of positional changes in neural monitoring endotracheal tube on amplitude and latency of electromyographic response in monitored thyroid surgery: Results from the Porcine Experiment.
abstract: The purpose of this study was to evaluate electromyography (EMG) amplitude and latency changes during tube dislocation in monitored thyroid surgery, which may be observed without recurrent laryngeal nerve injury.
  
  
  
  Duroc-Landrace piglets were intubated with the TriVantage EMG tube. We measured EMG changes during both upward and downward tube dislocation (10-20 mm) and rotation (45-90°) with continuous neuromonitoring.
  
  
  
  The EMG amplitude varied significantly with induced endotracheal tube rotation and depth changes. However, the EMG latency was relatively unaffected by such tube dislocation, just a transient artifactual latency change was observed in the situation of extreme amplitude variation.
  
  
  
  Amplitude changes without latency changes may be due to changes in tube position alone during surgery, but could still reflect a neurophysiologic event; amplitude changes during neuropraxic injury merit additional investigation. Thus, the combined event (concordant amplitude decrease and latency increase) serves as an appropriate adverse EMG event correlating with impending neural injury. © 2015 Wiley Periodicals, Inc. Head Neck 38: E1004-E1008, 2016.
authors.affiliation: Department of Surgery, KUMC Thyroid Center, Korea University Anam Hospital, Korea University College of Medicine, Seoul, Republic of Korea.
authors.forename: Hoon Yub
authors.initials: HY
authors.lastname: Kim
authors.affiliation: Division of Head and Neck Endocrine Surgery, Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Ralph P
authors.initials: RP
authors.lastname: Tufano
authors.affiliation: Division of Thyroid and Parathyroid Endocrine Surgery, Department of Laryngology and Otology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts.
authors.forename: Gregory
authors.initials: G
authors.lastname: Randolph
authors.affiliation: Department of General Surgery, Jagiellonian University, Medical College, Krakow, Poland.
authors.forename: Marcin
authors.initials: M
authors.lastname: Barczyński
authors.affiliation: Institute of Clinical Medicine, Faculty of Medicine, College of Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan.|Department of Otolaryngology-Head and Neck Surgery, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan.
authors.forename: Che-Wei
authors.initials: CW
authors.lastname: Wu
authors.affiliation: Institute of Clinical Medicine, Faculty of Medicine, College of Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan.|Department of Otolaryngology-Head and Neck Surgery, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan.
authors.forename: Feng-Yu
authors.initials: FY
authors.lastname: Chiang
authors.affiliation: Jilin Provincial Key Laboratory of Surgical Translational Medicine, Japan Union Hospital of Jilin University, Division of Thyroid Surgery, Changchun City, Jilin Province, China.
authors.forename: Xiaoli
authors.initials: X
authors.lastname: Liu
authors.affiliation: Department of Surgery, Kuma Hospital, Center for Excellence in Thyroid Care, Kobe, Japan.
authors.forename: Hiroo
authors.initials: H
authors.lastname: Masuoka
authors.affiliation: Department of Anesthesiology, Korea University College of Medicine, Seoul, Korea.
authors.forename: Akira
authors.initials: A
authors.lastname: Miyauchi
authors.affiliation: Department of Anesthesiology, Korea University College of Medicine, Seoul, Korea.
authors.forename: Soo Young
authors.initials: SY
authors.lastname: Park
authors.affiliation: Department of Surgery, KUMC Thyroid Center, Korea University Anam Hospital, Korea University College of Medicine, Seoul, Republic of Korea.
authors.forename: Hee Yong
authors.initials: HY
authors.lastname: Kwak
authors.affiliation: Department of Surgery, KUMC Thyroid Center, Korea University Anam Hospital, Korea University College of Medicine, Seoul, Republic of Korea.
authors.forename: Hye Yoon
authors.initials: HY
authors.lastname: Lee
authors.affiliation: First Division of Surgery, Research Center for Endocrine Surgery, Department of Surgical Sciences and Human Morphology, University of Insubria (Como-Varese), Varese, Italy.
authors.forename: Gianlorenzo
authors.initials: G
authors.lastname: Dionigi
mesh_terms: D000818:Animals; D004576:Electromyography; D005260:Female; D064795:Intraoperative Neurophysiological Monitoring; D007442:Intubation, Intratracheal; D061226:Recurrent Laryngeal Nerve Injuries / Q000517:prevention & control; D013552:Swine; D013961:Thyroid Gland / Q000601:surgery*
keywords: amplitude; electromyography; latency; recurrent laryngeal nerve; thyroid