Double upper incisor teeth as a rare cause of difficult intubation

Abstract

A 32 years old female weighing 50 kg, ASA I was scheduled for cholecystectomy. Her preoperative airway examination revealed bucked teeth, mouth opening 4 cm, mallampati grade II with normal neck mobility and no other obvious airway deformity. General anesthesia was planned for the procedure. In operating room, routine anesthesia was induced with fentanyl 100 µg and thiopentone sodium 250 mg. Mask ventilation was assessed and muscle relaxation was achieved with vecuronium 5 mg. On direct laryngoscopy with Macintosh size 3 blade, we noticed that patient had double upper incisors (Figure). Only epiglottis could be visualized even with external laryngeal manipulate. Two intubation attempts with intubating stylet led to esophageal intubation. Intubating laryngeal mask airway was attempted but failed. Face mask ventilation was still adequate and vitals were stable. Thereafter an attempt was made to insert Proseal laryngeal mask airway (PLMA) No 3. It was appropriately placed in single attempt as judged by adequate chest rise and P_etCO₂ waveform. Anesthesia was maintained with isoflurane in oxygen and nitrous oxide mixture and maintenance doses of vecuronium. Surgery proceeded uneventfully. At the end of surgery, relaxation was reversed and PLMA was removed. Postoperative course was uneventful.