Use of intubating laryngeal mask airway for intubation in patient with massive goitrous thyroid

Abstract

Sir, Large thyroid masses are a nightmare for the anaesthesiologist not only because of thyroid endocrinal abnormality but also because of difficult airway.[1] Fiberoptic bronchoscopy for tracheal intubation is considered the gold standard in such scenarios but may not be available sometimes.[23] We report a successful airway management in a patient with a large thyroid mass with distorted laryngeal anatomy using an intubating laryngeal mask airway (ILMA). A 65-year-old male was scheduled for total thyroidectomy for multinodular goitre. Patient complained of progressively increasing swelling over neck and difficulty in speaking, swallowing and breathing since last six months. The swelling extended superiorly up to the chin, laterally up to the posterior border of sternocleidomastoid and below up to the suprasternal notch (size, 30 × 20 cm) [Figure 1a and b]. There was prominence of veins over the mass and also over the anterior chest. Airway assessment revealed adequate mouth opening, modified mallampati class MMC II and neck movements were restricted. Investigations revealed normal haemogram, biochemical and thyroid profile. Indirect laryngoscopy revealed fixed left vocal cord and left pyriform fossa was not opening up. Soft tissue neck X-ray revealed compression and right deviation of trachea [Figure 2]. Contrast-enhanced computed tomography scan of neck and chest showed compression and right anterior displacement of the trachea. After overnight fasting, pantoprazole (40 mg) and glycopyrrolate (0.2 mg) was administered in the morning of surgery. In the operation room, routine monitors were attached. Lignocaine (4%) gargles were done. Left radial artery was cannulated. Anaesthesia was induced with sevoflurane (6%) in 100% oxygen. After lignocaine spray (10%), laryngoscopy revealed Cormack lehane CL Grade III. Even after manipulating the thyroid mass externally, the glottic chink could not be visualised. We could only appreciate a small hole in the left lateral aspect of the oral cavity and glottis was oedematous. We tried to negotiate the tube with a stylet but could not achieve tracheal intubation. Even bougie could not be negotiated. We attempted intubation using ILMA and optimal ventilation was achieved after adjusting the ILMA handle in different directions. This was achieved only when ILMA was rotated laterally and anteriorly. Stabilising the ILMA at this position of best ventilation and optimal capnograph, endotracheal tube was gently inserted and successful intubation was achieved. Thereafter the anaesthetic procedure was uneventful.Figure 1: (a, b). Patient with a larger thyroid massFigure 2: X-ray soft tissue neckWe predicted difficulty in tracheal intubation in our patient. Fiberoptic bronchoscope was not available with us for this patient. Tracheostomy as a definitive airway was not possible in our patient because of the large thyroid mass extending till the suprasternal notch and also due to airway distortion. So we planned to topicalize the airway and to secure the airway under sevoflurane induction. Since the endotracheal tube could not be negotiated in multiple attempts even after using bougie and stylet and manipulating the thyroid mass, ILMA was used as a rescue attempt. By manoeuvring the ILMA based on the predicted location of the glottic chink to achieve optimal ventilation helped us to adjust the ILMA cuff in line with the glottis and thereafter tracheal intubation was achieved in the first attempt. ILMA has been attempted earlier for tracheal intubation in patients with larger goitre but intubation was not successful though ventilation was easy.[4] They presumed that it could be because of distorted laryngeal anatomy and they performed standard manoeuvres for achieving the tracheal intubation. But we suggest that the manoeuvres need to be done on the basis of the predicted location of the glottic opening. We suggest that achieving optimal ventilation by ILMA could help in aligning the glottic chink and thus successful tracheal intubation could be done in a patient with a large goitrous thyroid with distorted laryngeal anatomy.