Left molar approach using adult C-MAC videolaryngoscope for airway management of a child with nasopharyngeal carcinoma extending to hypopharynx

Sir,

Airway management in patients with tumours involving airway is a daunting task for anaesthesiologist. In case of children, psychological and physiological issues further complicate the management. Emergency surgery at a setup ill-equipped for children makes the situation even more challenging. A 6-year-old 18 kg child who had been undergoing chemotherapy (cisplatin and paclitaxel) at our hospital for small cell carcinoma of nasopharynx presented with acute onset stridor and respiratory distress. He was unable to lie down and was posted for emergency tracheostomy and direct laryngoscopy-guided biopsy of the lesion. Computerised tomography scan revealed a 5.7 × 6.4 × 8.1 cm homogenously enhancing mass lesion in the right half of nasopharynx with obliteration of posterior choanae and lateral extension to paranasopharyngeal space with erosion of the right pterygoid plate [Figure 1]. Superiorly, there was intracranial extension into the right temporal lobe. Inferiorly, it shows displacement with scalloping of the right half of the soft palate and involving the base of the tongue and abutting the hyoid bone. On examination, the right nasal cavity was full of purulent discharge and ptosis was present in the right eye [Figure 2]. The oropharynx was occupied with the tumour while the left side was apparently free. Due to pressure of the mass, the hard and soft palate was bulging into the oral cavity on the right side. Because of oral pathology, supraglottic airway was not feasible and paediatric fibre-optic bronchoscope (FOB) was not available. Adult FOB and C-MAC videolaryngoscope (VL) size 3 blade along with conventional Macintosh laryngoscope and tracheal tube introducer were arranged. The mouth opening of the child was 3 cm and was sufficient for adult VL insertion. The child had been fasting for the past 8 h and after informed consent from parents; he was shifted to the operation theatre. An intravenous access was secured and monitoring instituted. After gargling 2% viscous lignocaine, an attempt of awake laryngoscopy was tried which proved futile as the child was uncomfortable in lying down. Hence, inhalation induction with preservation of spontaneous respiratory efforts was planned and emergency tracheostomy was kept ready as a back-up. The child was preoxygenated in sitting position and then anaesthetised with sevoflurane (3–8%) in semi-sitting position. After loss of eyelash reflex, the child was made supine and laryngoscopy was done with C-Mac size 3 blade using the left molar approach. Cormack-Lehane Grade 2a was obtained which improved to Grade 1 with optimum external laryngeal manipulation. After spraying the glottic aperture with lignocaine 10%, the trachea was intubated with 5.5 internal diameter cuffed endotracheal tube (ETT) and its placement confirmed with capnography tracing. Thereafter, intravenous induction and neuromuscular blockade were initiated. Biopsy of perilaryngeal and pharyngeal tumour tissue was taken using C-MAC VL. Tracheostomy was done using #6 tracheostomy tube. Recovery from anaesthesia was uneventful.

Figure 1.

CT scan image photo showing extent of tumor and involvement of right side of oropharynx

Figure 2.

Photograph of the child with nasopharyngeal carcinoma

A conventional laryngoscopy by inserting the laryngoscope through the right angle of the mouth and displacing the tongue to other side would have been difficult in such a scenario as the tumour would have hindered the view. VL provides no line of sight view as camera is located at tip of its blade. However, a midline videolaryngosocpy requires the ETT to be inserted from the right side which was occupied with tumour in our case. Hence, even though satisfactory glottic view might have been obtained with midline approach videolaryngosocpy but intubation would have been difficult due to lack of space. Hence, use of the left molar approach was reported by Saini et al. for intubation in an adult with massive neurofibroma of face.[1] Molar approach using Macintosh blade has also been described previously for intubating adults with intra-oral masses obscuring the midline path for laryngoscopy.[2] The left molar approach has been shown to improve glottic view by providing a straighter path to the glottis obviating the need for alignment of oral and laryngeal axis.[3] Molar approach to intubation has been successfully used for intubation in a neonate for surgical excision of large intra-oral cyst when convention laryngoscopy had failed.[4] C-Mac VL, in addition, helps improve glottis view further by shifting the line of view to the tip of the blade.[5] The combination of the two proved useful by providing a good view of the larynx with minimal tissue distraction force despite extensive tumour spread till the perilaryngeal space.

The use of adult C-Mac for the left molar approach in a child for intubation provides shorter and straighter path to glottis for the right-sided oropharyngeal mass improves the view and ensures easier intubation. In our opinion, this combination is ideal in such a scenario with intra-oral/pharyngeal masses on the right side of oral cavity.

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Conflicts of interest

There are no conflicts of interest.