To the editor:
Ankylosing spondylitis is a chronic, autoimmune, and progressive spondyloarthropathy affecting the spine and sacroiliac joints.1 The cervical spine is involved late in the disease, leading to restriction of the neck movement and head rotation, making the alignment of the oral, pharyngeal, and laryngeal axes impossible and resulting in potentially difficult airway for tracheal intubation.2 The Airtraq (Prodol Ltd, Vizcaya, Spain) is a recently introduced airway device to facilitate tracheal intubation in patients with both normal and difficult airways. We describe two patients with severe ankylosing spondylitis who were successfully intubated using Airtraq laryngoscope (Prodol Ltd.).
The first case was a 40-year-old male patient suffering from ankylosing spondylitis and who was scheduled for total hip replacement. Airway assessment revealed a restricted mouth opening, with Mallampati grade IV view and an interincisor gap of <2 cm. Neck mobility was restricted, and the thyromental distance was <6.5 cm. X-ray of cervical spine showed fusion of the posterior elements at all levels. The second case, a 65-year-old female known to have ankylosing spondylitis, was planned for subtotal thyroidectomy. Airway examination revealed a restricted mouth opening, with Mallampatti grade III view, and an interincisor gap of <3 cm. Thyromental distance was <6 cm with severe limitation of neck movements. X-ray of cervical spine showed gross osteopenia with complete fusion of posterior elements, end plate sclerosis and decreased joint space at C4–C5 and C5–C6 levels. After obtaining written informed consent from the patients, assessment of difficult intubation was made and both patients were planned for general anesthesia. On the day of the surgery, the patients were premedicated with intravenous (i.v.) midazolam 2 mg and intramuscular (i.m.) glycopyrrolate 0.2 mg. The patients were instructed to lie down in a supine position with the head supported by pillows, and all standard monitoring procedures were applied. A difficult airway cart was kept ready. Anesthesia was induced with i.v. fentanyl 1 μg/kg and i.v. propofol 2 mg/kg. After confirming adequate bag mask ventilation, neuromuscular relaxation was made possible with 1.5 mg/kg succinylcholine given intravenously. The table was adjusted to the head down position with flexion of both knees. The blade of the optical laryngoscope was introduced into the oral cavity in the midline over the base of the tongue and the tip positioned in the vallecula. Tracheal intubation was performed successfully with standard-sized endotracheal tube (PVC) in the first attempt after an adequate visualization of the vocal cords which required minor adjustments of Airtraq laryngoscope and wrist movement. The intraoperative course in both patients was uneventful, and the patients were extubated after adequate reversal of neuromuscular blockade.
Airtraq laryngoscope (Prodol Ltd) is a newly introduced intubation aid. The extreme curvature of the blade and optical components helps in the visualization of the glottis without the need for aligning the three airway axes (i.e., oral, pharyngeal, and laryngeal). It also does not obstruct the endoscopic view of the vocal cord during laryngoscopy because of its built-in conduit for endotracheal tube.3 Studies have reported the effectiveness and utility of the Airtraq laryngoscopy for tracheal intubation in patients with cervical spine immobilization and in morbidly obese patients.4, 5
Dimitriou et al6 showed that in their serial cases (four patients) of difficult airway awake intubation with Airtraq laryngoscope was successful. Basaranoglu et al7 also successfully used Airtraq laryngoscope as a rescue device for a failed awake fibreoptic intubation in a patient with severe ankylosing spondylitis. We successfully used Airtraq laryngoscope for intubation in our patients with restricted neck movements and in patients whose three oral, pharyngeal, and laryngeal axes were not in proper alignment.
We therefore conclude that intubation with Airtraq laryngoscope is a good option for elective intubation in patients with ankylosing spondylitis.
