Videoendoscope-guided nasotracheal intubation in ankylozing spondylitis.

Sir,

Loss of airway control is always a possibility in patients with difficult airway. Formulation of a definite strategy is difficult as clinical situations vary considerably. In a difficult airway, such as advanced ankylozing spondylitis (AS), conventional laryngoscopy may become difficult but a good view of laryngeal inlet can be achieved by videolaryngoscope. We recently managed a 42-year-old male AS patient, with cervical/thoraco-lumbar vertebrae involvement and fixed flexion deformity, for open reduction and internal fixation for fracture of shaft left femur [Figure 1]. His neck movements were grossly restricted and painful. He had restricted mouth opening (2 cm), thyromental distance of only 3 cm, and limited mobility of temporomandibular joints with a grade-IV Mallampati score. X-rays of cervical and dorsolumbar spines showed fusion of posterior elements [Figure 2]. An awake tracheal intubation was planned. In the absence of videolaryngoscope and fibreoptic bronchoscope, we introduced an 8-mm forward-view upper gastrointestinal videoendoscope orally to obtain a clear view of laryngeal inlet without much manipulation of the neck [Figure 3]. A15Fr malleable bougie was introduced via the left nostril and passed through the glottis under vision. A 7.5-mm cuffed endotracheal tube was then railroaded past the glottis over the bougie [Figure 4]. The endoscopic procedure is displayed as [Video].

Figure 1

Patient profile

Figure 2

X-ray of cervical spine (lateral view)

Figure 3

Videoendoscope showing both esophageal and laryngeal inlets

Figure 4

Photograph showing tracheal tube being railroaded over the bougie

Anesthesia options were either central neuraxial block or general anesthesia. Patient positioning and needle placement were anticipated to be difficult due to ossification of interspinous ligaments, syndesmophytes between vertebrae, bridging ankylosis, and bilateral involvement of hip joints. Abnormal spinal curvature could lead to unpredictable level of block. Central neuraxial block is frequently unsuccessful in AS patients with severe spinal involvement.[1] Airway could be secured with direct laryngoscopic intubation, blind nasal intubation, laryngeal mask airway, fiberoptic bronchoscope (FOB) guided intubation, retrograde intubation, tracheostomy, and videolaryngoscope-guided intubation. High failure rate was reported during blind nasal technique and repeated attempts could injure the already distorted structures resulting in loss of vision making subsequent FOB difficult. The stiff cervical spine does not allow the required movement of a tracheal tube for its entry into larynx. The supraglottic airway devices, such as laryngeal mask airway (LMA), intubating LMA,[23] and proseal LMA were not considered as they mandate a mouth opening more than 20 mm and an angle of greater than 90° between oral and pharyngeal axes. Awake FOB-guided tracheal intubation is still the safest choice in such cases. However, mucosal injury may result in increased secretion or bleeding, obscuring its view. Videolaryngoscopy provides better view of laryngeal inlet and vocal cords in difficult airway situations even in neutral neck position with a success rate of 96%.[4] Retrograde intubation needs definite identification of anterior anatomical structures of neck. During the blind passage of the guide wire, obstruction may occur at epiglottis, arytenoids, and vocal cords resulting in injuries.[5] Tracheostomy is also another option, but even an experienced ENT surgeon prefers to secure the airway before tracheostomy in an elective surgery. We tried to approach the airway with a technique, which is safe and easy to conduct using the best-available resources.

The videoendoscope is well tolerated by an awake patient and gives a clear view of the laryngeal inlet. The intubation was possible under vision without much manipulation of the neck. A bougie can be manipulated by a forceps using the biopsy channel, but it has certain drawbacks. As the process is time consuming, emergency settings and pediatric patients may not be the right choice for this procedure. A videoendoscope can be an alternate and valuable instrument in the anesthesia armamentarium.