Validity of rhinometry in measuring nasal patency for nasotracheal intubtion

Numerous techniques have been used to reduce epistaxis during nasotracheal intubation. Rhinometry can assess nasal patency in preoperative conditions. However, the possible role of rhinometry in routine nasotracheal intubation has not been studied. One hundred and one patients undergoing dental and maxillofacial surgery that required general anesthesia and nasotracheal intubation were enrolled. We examined whether symmetry or any asymmetry in bilateral airflow patterns by condensation of the expiration, assessed by preoperative rhinometry on seated position, increased the incidence of epistaxis and the need for a nasogastric catheter to guide the endotracheal tube into the oropharynx. We also compared the incidence of changing the site of nasal intubation between the assessment by rhinometry and by cone-beam computed tomography analysis of nasal airspace in the inferior meatus. Patients with any asymmetry in bilateral airflow patterns were 18 % (n = 18), the remaining 82 % (n = 83) had symmetric bilateral nasal cavities. Patients with any asymmetry were more likely to need a guiding nasogastric catheter than patients with symmetry (22 vs. 3.6 %, p = 0.018). The incidence of epistaxis was higher in patients with any asymmetry (39 %) than those with symmetry (16 %), but there was no significant difference between groups (p = 0.055). The site of intubation was changed more frequently based on cone-beam computed tomography analysis than by rhinometry (38 vs. 11 %, p = 0.043). Preoperative rhinometry may be a valuable objective tool to assess nasal patency for nasotracheal intubation in patients who undergo dental and maxillofacial surgery.