Airway management using O2 flush via Cook airway exchange catheter® for microlaryngeal surgery

Corresponding author: Hyung Tae Kim, M.D., Department of Anesthesiology and Pain Medicine, Presbyterian Medical Center, Junghwasandong 1-ga, Wansan-gu, Jeonju 560-750, Korea. Tel: 82-63-230-1593, Fax: 82-63-230-8169, E-mail: [email protected] This is an open-access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http:// creativecommons.org/licenses/by-nc/3.0/), which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. CC A 31-year old male patient who was 173 cm tall and weighed 67 kg visited our ENT clinic with dyspnea and laryngeal papilloma as his main complaints. According to laryngoscopic findings, a diffuse large papilloma was observed at the posterior wall of the left subglottis (Fig. 1A). The patient was scheduled for the removal of the papilloma under general anesthesia. Since the patient was adamantly opposed to invasive procedures such as a tracheostomy, awake intubation wasconsidered for safety reasons, but finally a fiberoptic bronchoscopy (FOB) and cricothyroidotomy set were prepared in case of trachea obstruction, considering that the size of the tumor was not large enough to obstruct the trachea. Anesthesia was induced with propofol, remifentanil, and rocuronium. Fortunately, ventilation was satisfactory, and tracheal intubation was performed. A tracheal tube 6.0 mm in inner diameter (ID) was inserted. Upon completion of preparations for surgery, an attempt was made to replace the tracheal tube with a tube that was 5.0 mm in ID using a Cook airway exchange catheter (CAEC: Cook Critical Care, Bloomington, USA) with a 14.0 of French size, 83 cm of length and 3.0 mm of ID, but only the CAEC was left in due to difficulty in surgery, and the tracheal tube was removed to surgery (Fig. 1B). The CAEC was fixed at the teeth after fitting at 22 cm because the length between the teeth and the superior aspect of the carina through FOB using a tracheal tube was 22 cm. In order to immediately reintubate and monitor end-tidal CO2 (EtCO2) in case of problems in ventilation or oxygenation, an adapter and the tracheal tube were left on the CAEC (Fig. 1C). Additionally, an injector for high-frequency jet ventilation (HFJV) was also prepared (Fig. 1D). For pre venting aspiration, the patient’s position was changed to the Trendelenburg position (Fig. 1C). In an attempt to avoid risks of developing ignition caused by the electrocautery, continuous ventilation was replaced by the onand-off procedure; when the pulse oximeter oxygen saturation (SpO2) of the patient fell to 90% or below, the procedure was stopped, and the reservoir bag was filled with an O2 flush; and after bagging at 100-120 times/minute, and the peak inspiratory pressure did not exceed 30 cmH2O resulting in an SpO2 of at 95% or greater, the procedure was resumed. At the end of the operation (Fig. 1C), a tracheal tube that had a 6.0 mm ID was intubated. Since microlaryngeal surgeries are performed under general anesthesia, small-diameter endotracheal tubes or jet ventilation are generally used for tracheal airway management according to the size and location of tumors. As one of the most useful methods of airway management in laryngeal surgery, jet ventilation, has been widely used because the view of the larynx is not blocked [1]. Supraglottic jet ventilation is a method of jet oxygenating via the vocal cords, which is ideal for surgical exposure, but anesthesiologists experience difficulty when using this method of airway management. Moreover, supraglottic jet ventilation may cause gastric distension because of high pressure and malalignment, inefficient or ineffective ventilation caused by barotraumas and malposition, and many potential complications including aspiration of blood and debris in the hypercarbia and bronchi [2,3]. Subglottic jet ventilation is a method using a small tube via the glottis below the vocal cord, which requires a tube and an injector. Subglottic