[Tracheal intubation in patients with Williams syndrome]

Williams syndrome is caused by the deletion of genetic material from chromosome 7, including the elastin gene. Affected individuals frequently have connective tissue disorders and skeletal hypoplasia, resulting in micrognathia and mandibular retrusion. These conditions hinder adequate visualization of the larynx and render intubation difficult. We used different methods of tracheal intubation for two patients with Williams syndrome. The first case was a 35-year-old woman with micrognathia, mandibular retrusion, and a Mallampati class III airway, scheduled for mitral valve replacement. She had a three fingerbreadth oral aperture, 3.0 cm mandibulohyoid distance, and 30 degree neck flexion. Since she had previously been successfully intubated at age 18 for patch enlargement of the aorta and extended aortoplasty, we elected to use intravenous anesthetic agents for this intubation. After administration of diazepam and fentanyl, mask ventilation was difficult and the direct laryngoscopic view was Cormack grade IV. Fortunately, blind orotracheal intubation using a Mallinckrodt tracheal tube with direct laryngoscopy was accomplished on the first attempt. The second case was a 71-year-old woman with micrognathia, slight mandibular retrusion, macroglossia, and a Mallampati class IV airway, scheduled for sigmoidectomy and insertion of a ureteral stent. She had a 2.5 fingerbreadth oral aperture, 4.0 cm mandibulohyoid distance, and 30 degree neck flexion. From our experience with the first patient, we expected difficult ventilation and intubation. After 8% lidocaine spray to the larynx, and then 4% lidocaine spray to the vocal cords and trachea using a bronchoscope, we accomplished awake, fibreoptic-guided orotracheal intubation easily and quickly on the first attempt using a Parker Flex-Tip tube. Difficult tracheal intubation should be anticipated in Williams syndrome patients. Awake, fibreoptic-guided technique is easier and safer than direct laryngoscopy for intubating such patients.