Suction Catheter as a Guide for Nasotracheal Intubation Under General Anesthesia

Inclusion Criteria: * Patient undergoing elective oral and maxillofacial surgery in which nasotracheal intubation is preferred over orotracheal intubation to optimize surgical access. * ASA physical status I-II * Thai adult, aged 18-65 years old * Normal Body Mass Index (BMI = 18.5-24.9) Exclusion Criteria: * Anticipated difficult airway (e.g., Mallampati classification 3-4, interincisal distance \< 35 mm., thyromental length \< 60 mm., limited neck mobility) * Nasal infection or systemic infection * Abnormal coagulation status or having bleeding disorder or taking anticoagulation/antiplatelet medication * History of recurrent epistaxis since adulthood * Allergic rhinitis that necessitates the use of glucocorticoids, antihistamine, antileukotriene or decongestant in the past 4 weeks * History of nasal trauma or abnormality (e.g., trauma in mid-face region, nasal surgery, nasal polyps, chronic sinusitis, abnormal nasal vasculature, tumor in nasal region, radiotherapy in nasal region) * Craniofacial deformity syndrome * Using nasal oxygen or Continuous Positive Airway Pressure (CPAP) * Previous nasotracheal intubation or nasogastric tube placement within 3 months * Diagnosed as having a mental disorder Drop-out criteria: * Unable to complete intubation procedure * Intubation failed on both nostrils * When intubation was only possible with a tube smaller than 6.5 internal diameter (ID) in male and 6.0 ID in female * Inadequate data collection