Clinical experience of airway management and tracheal intubation under general anesthesia in patients with scar contracture of the neck

BACKGROUND: Because patients with scar contracture of the neck are at a high risk of loss of the airway control after anesthesia induction, awake intubation is usually recommended. This retrospective clinical study was designed to evaluate the possibility, safety and efficacy of airway management and tracheal intubation under general anesthesia in such patients. METHODS: This retrospective study included 1683 patients from January 1994 to December 2006 with scar contracture of the neck, aged 1.5 - 67.0 years, who were scheduled for elective plastic surgery under general anesthesia in Plastic Surgery Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College. Based on the results of the preoperative airway assessment, the patients were classified into group 1 (including 1375 patients with the atlanto-occipital extension of > 20 degrees and the Mallampatti's grade I or II) and group 2 (containing 308 patients with the atlanto-occipital extension of < 20 degrees and the Mallampatti's grade III or IV. In group 1, the intravenous induction and maintenance of anesthesia and succinylcholine for muscle relaxation were used. The intubation was done using a modified Macintosh technique. In group 2, the total intravenous anesthesia (TIVA) or the sevoflurane inhalation anesthesia was chosen and the spontaneous breathing was reserved during anesthesia. The intubation was performed by a fiberoptic stylet laryngoscope (FOSL). The number of intubation attempts, intubation time and relative complications were observed and recorded in all patients. RESULTS: In group 1, the intubation was accomplished during the first attempt in 1279 cases (93%) and the intubation time was < 3 minutes in 1304 cases (95%). In group 2, the intubation was completed by the first attempt in 114 patients (37%) and 123 patients had an intubation time of < 3 minutes (40%). Tracheal intubation was successful by the second or third attempt in 96 patients in group 1 and 156 patients in group 2. Thirty-eight patients required four or more attempts which only occurred in group 2. The incidence of traumatic complication was 2.6% and 9.7% with one intubation attempt in groups 1 and 2, respectively, 12.5% and 17.0% with multiple intubation attempts (one vs multiple attempts in both groups, P < 0.001). All non-traumatic complications occurred in group 2 and laryngospasm and hypoxemia were more common in patients using the TIVA compared to those using the sevoflurane inhalational anesthesia (P < 0.001). CONCLUSIONS: This study demonstrated that with a precise airway evaluation, an adequate preoperative preparation and a pre-planned failed intubation strategy, the anesthetist who was experienced in the difficult airway management could safely perform airway control and tracheal intubation under general anesthesia in patients with scar contracture of the neck. We believe that this technique may be very valuable for the management of a known difficult airway because it is comfortable for the patient and saves time for the anesthetist.