Improving the penetration of ototopicals through tympanostomy tubes: role of surfactants.

OBJECTIVE

To evaluate the ability of surfactants to increase the penetration of ototopicals through tympanostomy tubes (TT).

METHODS

An in vitro model was used to test the penetration of ototopicals with and without two surfactants (docusate sodium and beractant) through fluoroplastic and titanium TTs. The model was created by placing a TT through a perforation (myringotomy) in a model of the tympanic membrane (silastic sheet) fixed between the ends of two 1 mL syringes. Measurements were recorded of the maximum height various solutions (distilled water, soapy water, ofloxacin otic, ciprofloxacin/dexamethasone otic) achieved before penetrating the TTs (1.27 mm Reuter Bobbin titanium, 1.27 mm fluoroplastic). These same measurements were then performed with the addition of docusate sodium or beractant to the distilled water and each of the ototopical solutions.

RESULTS

The addition of docusate sodium significantly increased the penetration of water and ofloxacin otic through both types of TTs. It significantly increased penetration of ciprofloxacin/dexamethasone otic through fluoroplastic tubes with a trend towards increased penetration through titanium tubes. Adding beractant showed a modest trend toward increasing the penetration of both ototopicals in fluoroplastic tubes which did not reach statistical significance.

CONCLUSIONS

These results demonstrate that the penetration of ototopicals through TTs can be improved by the addition of surfactants. Increasing the penetration of ototopicals may make them more effective in treating TT otorrhea. However, we strongly discourage clinicians from using these compounds clinically until their safety has been established.