The Clarus Video System (Trachway®) intubating stylet, Biotronic Instrument Enterprise Ltd., Tai-Chung, Taiwan, R.O.C.) is a new video intubating stylet for tracheal intubation [1, 2]. Views of the laryngeal inlet and vocal cords are presented on the colour monitor via the distal camera. This airway equipment has been used for difficult intubation in simulated scenarios [3 but its clinical application during difficult tracheal intubation has not been investigated.
A 49-year-old man with a history of odontoid fracture was admitted after presenting with six months progressive bilateral upper limb weakness and sensory loss. Cervical spine radiographs demonstrated a C1-C2 subluxation. A halo vest frame (Halo Cervical Traction System 1223, PMT® Corporation, Chanhassen, MN, USA) was applied prior to surgical intervention. He was scheduled for C1 and C2 decompression and fusion. Pre-operative airway assessment revealed limited mouth opening (3 cm) and intact upper and lower dentition without overbite. We measured his thyromental distance as 6 cm and his Mallampati score was grade IV. His neck was fixed due to the halo vest. As general anesthesia with tracheal intubation was required for the surgery, we elected to proceed with an awake intubation.
Following informed consent, we placed the patient supine and slightly head-up. After establishing non-invasive monitoring and pre-oxygenation by facemask, we performed a trans-tracheal injection with 100 mg 2 % lidocaine and administered 50 μg fentanyl intravenously for light sedation. We used 10% lidocaine spray to anaesthetise the oropharynx. After placing an oral mouthpiece as a bite guard (E-Z-EM Inc, NY, USA) between his teeth, we performed tracheal intubation using the Trachway, over which a standard tracheal tube (7.5 mm ID, Unomedical Inc., McAllen, TX, USA) was fitted (Figure).
We visualised the anatomical structures on the monitor attached to the handle as we advanced the tube and stylet along the dorsum of the tongue. We easily identified the epiglottis and vocal cords at our first attempt. We then slid the tracheal tube off the stylet and advanced it into the trachea under direct vision. After removing the Trachway, we immediately inflated the endotracheal tube cuff.
The patient exhibited no reflex coughing or retching during the intubation procedure, and we did not need to move the neck or employ jaw thrust or external laryngeal manipulation.
This case report is the first describing the use of the Trachway intubating stylet for awake tracheal intubation in a patient wearing a halo vest although the Pentax Airway Scope (AWS; Pentax Corporation, Tokyo, Japan) has been described to aid tracheal intubation in a patient wearing a halo vest . The Trachway intubating stylet has the advantage of providing direct visualisation during tracheal intubation and therefore avoids blind and potentially traumatic airway manipulation. Also, in patients with limited mouth opening, insertion of a Macintosh laryngoscope blade into the patient’s mouth may be difficult or even impossible but the Trachway intubating stylet avoids this problem and can be selected as an alternative intubating device.
Mennonite Christian Hospital
No external funding and no competing interests declared. Published with the written consent of the patient.
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Figure 1 Trachway, preloaded with tracheal tube, was inserted into oral cavity.