Lung Isolation in the Setting of Vocal Cord Implantation

Abstract

Lung isolation after vocal cord prosthesis implantation is not described in the literature. Vocal cord implantation is performed in patients with vocal cord paresis or paralysis to improve phonation. The implant is inserted alongside the weak or paralyzed vocal cord, displacing the cord to the midline, to approximate with the opposite cord to achieve and restore phonation. Vocal cord medialization may be accomplished by autologous transplantation of the fascia or by using synthetic material. For vocal cord implantation surgery various anesthetic techniques are used, ranging from monitored anesthesia care or deep sedation, to a fully awake status to assess phonation for sizing of the implant. Here the authors discuss the case of a 74-year-old man, a Vietnam war veteran with history of laryngeal reconstruction due to injury during his military service who presented for thoracoscopic resection of a right middle lobe nodule. His history was significant for left vocal cord paralysis for which he had undergone vocal cord medialization with Teflon injection, followed by debulking of a Teflon granuloma and placement of a Silastic (silicone) implant (Fig 1). A preoperative flexible fiberoptic laryngoscopy demonstrated complete left vocal cord paralysis, with only mild glottic narrowing and otherwise normal anatomy of the aryepiglottic folds, false and true cords, and piriform sinuses. Written informed consent was obtained from the patient for research and publication. General anesthesia was induced with intravenous lidocaine, fentanyl, and propofol, and muscle relaxation was achieved with rocuronium. Video laryngoscopy with a GlideScope 4-blade yielded a grade 1 view of the glottis, and a 7.5-mm endotracheal tube (ETT) was introduced atraumatically to a depth of 24 cm at the incisors. A Rusch EZ-Blocker endobronchial blocker was placed under fiberoptic guidance, and appropriate positioning of the endobronchial cuffs in both mainstem bronchi was confirmed. Lung isolation was achieved quickly, and the case proceeded uneventfully. The patient was extubated after the surgery and was discharged home on postoperative day 1, with no hoarseness or difficulty with phonation. Lung isolation can be accomplished with a larger single-lumen ETT with intraluminal bronchial blocker, smaller-lumen ETT with extraluminal bronchial blocker, or double-lumen ETT. All of the aforementioned choices would pose a special challenge in the setting of preexisting vocal cord implantation, with a potential for dislodgment. The authors opted to use a single-lumen ETT, considering the outer diameter, inner diameter, better airflow dynamics, and EZ-Blocker for the ease of insertion and maintenance of one-lung ventilation. The recent article from Lou et al., “Tracheobronchial Trauma from Double-Lumen Tube Placement in Patients Undergoing Lung Transplantation,” is timely. 1 Lou SS Bethel M Reidy AB Helwani MA. Tracheobronchial trauma from double-lumen tube placement in patients undergoing lung transplantation [e-pub ahead of print]. J Cardiothorac Vasc Anesth. 2021 Apr 20; https://doi.org/10.1053/j.jvca.2021.04.020 Abstract Full Text Full Text PDF Scopus (1) Google Scholar Therefore, the authors emphasize that lung isolation in patients with vocal cord implantation poses a unique challenge. The authors prefer using an EZ-Blocker via ETT in the presence of a narrow glottic to promote the stability of the implant. Flexible fiberoptic bronchoscopy was performed to evaluate the airway anatomy and achieve an optimal position of the EZ-Blocker. 2 Campos J. Fiberoptic bronchoscopy for positioning double-lumen tubes and bronchial blockers. In: Principles and practice of anesthesia for thoracic surgery. Springer, Cham, Switzerland2019: 311-322 Google Scholar It is also preferable to have an anesthesiologist experienced in airway management to direct the ETT away from the paralyzed vocal cord where the implant is inserted. At the end of the surgery, the ETT may be replaced with a laryngeal mask airway to facilitate fiberoptic examination of the glottic area to evaluate for migration or dislodgment of the vocal cord implant. The authors have presented what they believe to be the first reported case of one-lung ventilation with vocal cord prosthesis in situ.