Soji Ozawa, Kazuo Koyanagi, Akihito Kazuno, Miho Yamamoto, Yamato Ninomiya, Kentarou Yatabe. Department of Gastroenterological Surgery, Tokai University School of Medicine, Japan
Introduction: Recurrent laryngeal nerve paralysis caused by lymph node dissection during thoracoscopic esophagectomy is one of the most important postoperative complications causing hoarseness, aspiration, pneumonia, or dysphagia. Continuous intraoperative vagus nerve stimulation for monitoring the recurrent laryngeal nerve function during thyroid or parathyroid surgery has been performed to avoid nerve injury. The aim of this study was to clarify whether such monitoring could be useful during thoracoscopic esophagectomy for esophageal cancer. To the best our knowledge, this is the first study of continuous nerve stimulation during thoracoscopic esophagectomy in a prone position for esophageal cancer.
Methods and Procedures: This study was a prospective, interventional, single arm, open-label study and was approved by the Institutional Review Board for Clinical Research, Tokai University. Twenty-eight patients with esophageal cancer were enrolled; all the patients were scheduled to undergo an elective thoracoscopic esophagectomy in a prone position with 3-field lymph node dissection. The nerve function was continuously monitored using NIM-Response® 3.0 (Medtronic Japan) with an EMG endotracheal tube and an APS electrode attached to the vagus nerve. The endoscopic diagnosis of vocal cord movement and the clinical diagnosis of hoarseness were assessed before and after surgery.
Results: The median patient age was 68.5 years; 23 males and 5 females were examined. Twelve patients received neoadjuvant chemotherapy, and 2 patients received neoadjuvant chemoradiotherapy. pStage 0, I, II, III, and IVa were observed in 4, 4, 12, 6, and 2 patients, respectively.Left recurrent laryngeal nerve paralysis occurred in 4 patients (14%) whose EMG amplitude had decreased to below 50% of the initial value. The cause of left recurrent laryngeal nerve paralysis was presumed to be excessive traction during the thoracoscopic procedure in 1 patient and during the cervical procedure in 2 patients, and thermal injury caused by energy devices during the thoracoscopic procedure in 1 patient. All 3 patients, who were followed up for more than 3 months, recovered from the temporary left recurrent laryngeal nerve paralysis.
Conclusion: Continuous intraoperative vagus nerve stimulation for monitoring the recurrent laryngeal nerve function during thoracoscopic esophagectomy for esophageal cancer revealed that the potential causes of left recurrent laryngeal nerve paralysis included not only thoracoscopic lymph node dissection, but also cervical lymph node dissection. This monitoring method seems to be useful for identifying harmful procedures intraoperatively and for establishing safer procedures while performing lymph node dissection in the vicinity of the recurrent laryngeal nerve.
Presented at the SAGES 2017 Annual Meeting in Houston, TX.
Abstract ID: 94672
Program Number: P480
Presentation Session: Poster Session (Non CME)
Presentation Type: Poster