Airway Management of a Patient with Microgenia Caused by Temporomandibular Joint Ankylosis for a Repeated General Anesthesia

Abstract

  We herein report the case of a 19-year-old woman with microgenia caused by temporomandibular joint (TMJ) ankylosis. The patient had a height of 155.8 cm and weight of 37.7 kg during the first surgery. To resolve severe disturbance of the mouth opening, TMJ mobilization and coronoidotomy were scheduled under general anesthesia. We performed intubation using surgical tracheostomy under conscious sedation, and the intraoperative course was uneventful. Four years after the first surgery, a second surgery for the extraction of wisdom teeth was scheduled before surgery to correct the deformity of the jaw. As the patient’s mouth opening range increased from 5 mm to 30 mm, we planned mask ventilation and nasal endotracheal intubation. Further, to avoid hypoxia due to hypoventilation, oxygenation was monitored using the oxygen reserve index (ORi^TM). General anesthesia was induced using propofol and remifentanil, and mask ventilation was easily attainable ; however, it was difficult to visualize the epiglottis using the McGRATH^TM MAC (McGRATH X BLADE). Consequently, we could not ventilate using a mask, and the oral airway device was ineffective. Finally, the insertion of a supraglottic airway device (Ambu^® AuraFlex^TM) resulted in an effective seal, and the patient could be ventilated. We tried to expand the space in the pharynx using the McGRATH^TM MAC and insert a fiberscope through the nasal passage. This method allowed completion of fiber-optic nasal intubation. The ORi^TM was maintained from 0.2 to 0.4, and SpO₂ was maintained at 100％ during the intubation period.