Post-tympanostomy otorrhea: a randomized clinical trial of topical prophylaxis

Myringotomy with the insertion of tympanostomy tubes has become the most frequently performed otolaryngologic procedure, and otorrhea is the most common post-tympanostomy complication. Many otolaryngologists routinely use prophylactic topical antibiotic solutions when performing tympanostomy tube placement. Relatively little has been written regarding early post-tympanostomy otorrhea and scarcely any examining the efficacy of such prophylaxis. The current study is a randomized clinical trial to critically evaluate the efficacy of prophylactic otic drops after tympanostomy tube placement. The ototoxic potential of these solutions, combined with constant pressures to decrease medication expenses and eliminate unnecessary use of antibiotics, makes determination of the shortest effective course of application paramount. Subjects were randomized at the time of surgery into one of three groups: one group received no prophylaxis, a second group received gentamicin otic drops immediately after tympanostomy tube placement in the operating room only, and the third group received an additional 48 hours of drops (4 drops in each ear, three times a day). All patients were seen within 2 weeks postoperatively. An overall early post-tympanostomy otorrhea incidence of 8.7% is documented with 12%, 8.8%, and 5.6% for each study group, respectively. While these findings may suggest possible efficacy of topical prophylaxis, a statistically significant difference between the treatment groups was not proved (p = 0.62). Further analysis by subdivision of the patients, on the basis of middle ear cavity finding at the time of surgery, reveals a highly significant statistical association of the occurrence of post-tympanostomy otorrhea in ears having mucoid effusions (p less than 0.001) as compared to ears without effusion or with serous effusions.(ABSTRACT TRUNCATED AT 250 WORDS)