Objective: To determine the effect of surfactant alone and with other medications delivered intranasally as a metered dose inhaler (MDI) aerosol on the resolution of experimentally induced otitis media with effusion (OME).
Background: Eustachian tube dysfunction is a primary factor in the pathogenesis of OME. Intranasal surfactant via MDI has been shown in this laboratory to reduce passive opening pressure of the eustachian tube in normal gerbils and mice.
Study design: OME was developed in 35 gerbils by transtympanic injection of 10 microg lipopolysaccharide from Klebsiella pneumoniae. Pretreatment otomicroscopy and tympanometry were performed to exclude pre-existing middle ear disease, and postinfection evaluations were performed on alternate days for a period of 30 days. Five animals received no treatment (control group); four were treated with propellant only (placebo); seven received surfactant alone; eight received surfactant and betamethasone; and six received surfactant with phenylephrine. All medications were sprayed intranasally as an aerosolized MDI and administered daily from postinfection day 2 onward.
Results: OME resolved after 16.0 +/- 0.44 days (mean + SD) in controls. There was no difference seen in the placebo or the surfactant with phenylephrine groups. Treatment with surfactant yielded resolution in 10.57 +/- 0.37 days; this was reduced to 8.57 +/- 0.37 days with surfactant plus betamethasone. These differences are statistically significant. There was no recurrence of OME in any group.
Conclusion: This study demonstrates that using an aerosolized MDI surfactant with and without betamethasone decreases the duration of OME in this in vivo gerbil model.