Objective: To evaluate the effectiveness of using mouthpiece nebulization and nasal swab stick packing for topical anesthesia in awake fiberoptic nasotracheal intubation.
Material and Method: This was a prospective descriptive study of 30 patients with ASA I-II who underwent elective surgery and suspected of difficult intubation between March 2004 and June 2006. After 2% lidocaine 5 ml was nebulizated in a micronebulizer using oxygen 10 L/min as a driving gas through a standard mouthpiece and 10% cocaine 1 ml on cotton swab-stick was applied to the selected nostril for 15 min, fiberoptic nasotracheal intubation was done while the patient was awake. If the patient had severe gag or cough reflex, 1% lidocaine 5 ml per each time could be injected through the working channel of the fiberoptic bronchoscope. The descriptive statistics were calculated by using SPSS version 11.0.
Results: The success rate of awake fiberoptic nasotracheal was 100%. The mean duration of awake fiberoptic nasotracheal intubation was 119.0 + 76.8 sec. The responses of the patient to instrumentation during 4 periods, i.e.: passing the endotracheal tube into the nose, passing the bronchoscope into the pharynx-larynx, passing the bronchoscope into the trachea-carina and passing the endotracheal tube into the trachea were, as follows: no response in about 53.3%, 63.3%, 23.3%,and 13.3%; mild pain or reflex in about 46.7%, 10%, 70%, and 86.7%; moderate pain or reflex in about 0%, 3.3%, 6.7%, and 0%; and severe pain or reflex requiring more local anesthetic in about 0%, 23.3%, 0%, and 0%, respectively. Despite complete topical anesthesia in the majority of the patients, two patients required 5 ml more 1% lidocaine and five patients required 10 mL more of the drug through the fiberoptic bronchoscope. There was no serious complication such as hypoxemia, arrhythmia. Twenty-four patients (80%) were satisfied with mouthpiece nebulization and nasal swab packing because they felt safe, did not have pain, and were comfortable; only three patients (10%) were dissatisfied because of numbness of the tongue and difficulty in swallowing; two patients (6.7%) had no comment; and one patient (3.3%) was unable to evaluate due to unplanned tracheostomy.
Conclusion: In the present study technique of topical anesthesia using 2% lidocaine 5 mL mouthpiece nebulization and 10% cocaine 1 mL soaked nasal swab stick packing is useful and safe for awake fiberoptic nasotracheal intubation in patients with suspected difficult intubation. 76.7% of the patient did not require more local anesthesia and 80% were satisfied with this technique.

Keywords: Nebulization, Awake fiberoptic nasotracheal intubation, Difficult airway, Topical anesthesia technique