A pilot study to determine the effects of nasal co-phenylcaine on drug-induced sleep endoscopy

The use of nasal decongestant and nasal anaesthesia is currently not recommended during drug-induced sleep endoscopy (DISE) according to the European position paper. The evaluation of the effects of nasal decongestant/anaesthesia on DISE has not been performed before and our aim is to perform a pilot study to determine whether nasal decongestants/anaesthesia affects DISE outcomes.

27 patients undergoing DISE for OSA or for simple snoring were included. On each patient, DISE was performed twice, before and approximately 10 min after the administration of two puffs of co-phenylcaine nasal spray (lidocaine hydrochloride 5%, phenylephrine 0.5%, and benzalkonium chloride 0.01%) into each nostril. A nasal peak inspiratory flow was used for the objective assessment of nasal airway obstruction. During the first and the second DISE the loudness of the snoring was also recorded.

Change in DISE total grading after nasal spray administration was not statistically significant. For the same grading, changes in percentage of contribution to collapse were not statistically significant. Sex, AHI, BMI, tonsils grade, presence of rhinitis, turbinate hypertrophy, nasal septal deviation, or nasal peak inspiratory flow limitation had no influence on the effect of nasal spray. Co-phenylcaine did not significantly influence the loudness of snoring.

Our pilot study supports the use of co-phenylcaine nasal spray during DISE and the positive effects of the nasal spray do not influence the grading outcome. Importantly, the decongestant enhances the nasal assessment during DISE and potentially aids in the diagnosis of nasal obstruction while the nasal anaesthetic component may be beneficial by reducing nasal discomfort during DISE and thereby helping to reduce the total dose of intravenous anaesthetic administered. However, further studies on a larger population are needed to confirm our results.