Non-operating room anaesthesia and difficult airway management in a case of ectopic lingual thyroid planned for magnetic resonance imaging.

Sir,

A five-year-old 19 kg female child diagnosed with an ectopic lingual thyroid with subclinical hypothyroidism was planned for a contrast-enhanced magnetic resonance imaging (MRI) of the neck for further evaluation under sedation. She was on follow-up for seizure disorder on tablet sodium valproate since 20 months of age and had an additional complaint of a swelling at the back of the tongue noticed around a month back. There was a history of the child preferably sleeping in lateral or prone position. Airway examination revealed a globular mass at the base of tongue visible on tongue protrusion [Figure 1a]. Neck X-ray lateral view showed an irregular shadow at the base of the tongue with the backward displacement of epiglottic shadow [Figure 1b].

Figure 1

(a) Globular mass at the base of tongue. (b) Neck X-ray lateral view

On the day of the procedure, after appropriate counselling of the child, an intravenous catheter was secured facilitated by the application of EMLA™ cream. Tip of the tongue was topicalised with lignocaine 10% spray and 20 μg inj fentanyl was given intravenous (IV). While the parents held the patient comfortably, a stay suture was taken with a silk 2-0 suture at the tip of the tongue with a margin of 1 cm to prevent tongue fall [Figure 2]. Both the ends of suture were left outside the mouth. Emergency cricothyroidotomy equipment was kept ready before starting the procedure. Patient was shifted on the patient table of machine in the parents' presence. MRI compatible pulse-oximetry and electrocardiography monitor were applied. Humidified oxygen was given at 4 L/min using a nasal cannula. IV propofol was given in aliquots till deep sedation was achieved and maintained at 50–75 μg/kg/min using a compatible infusion pump. Both ends of the suture thread were gently pulled and fixed using adhesive tape in such a manner that tip the of the tongue covered the vermilion border of the lower lip. Patient's respiratory movements were monitored throughout by visual examination and trans-thoracic impedance monitor with the aim to maintain spontaneous breathing. The procedure lasted for around 20 min, and the patient regained consciousness within 3–4 min of stopping the infusion. The suture was pulled out at this time and the child was observed in the recovery area for 1 h. She was discharged home in the evening uneventfully. Appropriate consent was obtained from the legal guardian of the patient for presenting this case report and related pictures in academic forums and journals.

Figure 2

Stay suture of the tongue

Numerous diagnostic and therapeutic procedures are now being performed outside the operation theatre constituting non-operating room anaesthesia (NORA).[1] Paediatric NORA requires more immobility and deeper levels of sedation for children who cannot endure the long and/or uncomfortable procedures.[2] Sedation is a continuum, and it is not always possible to predict the response of an individual patient. Thus, practitioners should be ever ready and able enough to rescue the airway in those patients in whom the level of sedation becomes deeper than intended,[3] and may require assistance in maintaining a patent airway and/or adequate ventilation.

The options in the present case for keeping the airway patent, such as oropharyngeal airway, nasopharyngeal airway or supra-glottic airway devices were not feasible due to the presence of the swelling and risk of trauma or bleeding from it [Figure 1]. Direct laryngoscopy and intubation were also expected to be difficult. Using ketamine for sedation might have been a safer option considering the airway control, but it was avoided due to the presence of a pre-existing seizure disorder. Tongue lip adhesion[45] is an established technique of keeping the airway patent in patients with congenital deformities, including Pierre-Robbin syndrome where there are glossoptosis and micrognathia leading to upper airway obstruction. Similarly in surgical cleft palate repair, stay sutures may be taken on tongue for the control of airway at the conclusion of surgical procedure. In the present case, it may have been prudent to remove the tongue suture after a period of observation in the recovery room instead of removing it immediately after the child regained consciousness.

The described technique may be practised in this subset of difficult airway cases presenting for NORA for safer airway management, to avoid airway-related mishaps and complications, especially when far from the operating room or an established anaesthesia setup.

Declaration of parental consent

The authors certify that they have obtained all appropriate patient consent forms. In the form, the guardians have given their consent for patient's images and other clinical information to be reported in the journal. The guardians understand that patients' names and initials will not be published and due efforts will be made to conceal identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.