Optimal depth of nim emg endotracheal tube for intraoperative neuromonitoring of the recurrent laryngeal nerve during thyroidect

Abstract
Background  Malpositioning of the endotracheal surface electrodes can result in dysfunction of intraoperative neuromonitoring (IONM) and
increase the risk of recurrent laryngeal nerve injury. The purpose of this study was to investigate the optimal depth of the
nerve integrity monitor (NIM) EMG endotracheal tube.

Methods  We enrolled 105 adult patients undergoing elective thyroidectomy. Each Medtronic Xomed NIM EMG endotracheal tube was placed
with the middle of the exposed electrodes well in contact with the true vocal cords under direct laryngoscopy. Function of
IONM was documented and the insertion depth was measured and analyzed.

Results  Ninety-nine (94.3%) patients had successful IONM with the initial endotracheal tube position. Six (5.7%) patients needed further
tube depth adjustment under fiberoptic bronchoscopy. All patients were finally had successful IONM. The optimal mean depth
was 20.6 ± 0.97 cm in men and 19.6 ± 1.0 cm in women (p < 0.01). There was the trend that taller subjects had a deeper tube depth (p < 0.05).

Conclusion  We concluded that the mean depth of the NIM EMG tube would be a useful reference value for detecting the malposition of electrodes
and adjusting the depth of tube during the operation.

Content Type Journal ArticleDOI 10.1007/s00268-008-9549-1Authors
I-Chen Lu, Kaohsiung Medical University Chung-Ho Hospital Department of Anesthesiology Kaohsiung TaiwanKoung-Shing Chu, Kaohsiung Medical University Chung-Ho Hospital Department of Anesthesiology Kaohsiung TaiwanCheng-Jing Tsai, Kaohsiung Medical University Chung-Ho Hospital Department of Anesthesiology Kaohsiung TaiwanChe-Wei Wu, Kaohsiung Medical University Chung-Ho Hospital Department of Otolaryngology - Head and Neck Surgery No.100, Tzyou 1st Road Kaohsiung 807 TaiwanWen-Rei Kuo, Kaohsiung Medical University Chung-Ho Hospital Department of Otolaryngology - Head and Neck Surgery No.100, Tzyou 1st Road Kaohsiung 807 TaiwanHsiu-Ya Chen, Kaohsiung Medical University Chung-Ho Hospital Department of Anesthesiology Kaohsiung TaiwanKa-Wo Lee, Kaohsiung Medical University Chung-Ho Hospital Department of Otolaryngology - Head and Neck Surgery No.100, Tzyou 1st Road Kaohsiung 807 TaiwanFeng-Yu Chiang, Kaohsiung Medical University Chung-Ho Hospital Department of Otolaryngology - Head and Neck Surgery No.100, Tzyou 1st Road Kaohsiung 807 Taiwan

Journal World Journal of SurgeryOnline ISSN 1432-2323Print ISSN 0364-2313 (Source: World Journal of Surgery)