Study objective: Assessment of the tympanic membrane is often impeded by th
e presence of cerumen. We compared the ceruminolytic effects of triethanola
mine polypeptide and docusate sodium in patients with cerumen.
Methods: We conducted a prospective, randomized, controlled, double-blind t
rial on a convenience sample of cooperative adult and pediatric patients pr
esenting to a university-based emergency department who required removal of
cerumen to visualize the tympanic membrane. Structured data collection was
performed, and the physician determined whether visualization of the tympa
nic membrane was partially or totally obscured by cerumen (interobserver ag
reement, rho=0.79). Patients received intra-aural instillation of 1 mL of e
ither docusate sodium or triethanolamine polypeptide in a liquid form. If n
ot completely cleared within 15 minutes, the external ear canal was irrigat
ed with 50 or 100 mL of normal saline solution and additional attempts to v
isualize the tympanic membrane were made. The main outcome was the proporti
on of ears in which the tympanic membrane could be totally visualized after
ceruminolytic instillation with or without irrigation. This study had 80%
power to detect a 40% difference between groups in the proportion of totall
y visualized tympanic membranes (chi(2) test, alpha=.05).
Results: Of 50 enrolled patients, 23 received triethanolamine polypeptide a
nd 27 received docusate sodium. Mean patient age was 40 years (range 1 to 8
1 years); 35% were female. Groups were similar in age, sex, and proportion
of completely obscured tympanic membranes at presentation (78%). The abilit
y to completely visualize the tympanic membrane was significantly greater a
fter treatment with docusate sodium versus triethanolamine polypeptide (81%
versus 35%; difference in proportions 47%; 95% confidence interval [CI], 2
2 to 71)particularly in children aged 5 or less (90% versus 0%; difference
in proportions 89%; 95% CI 50 to 100).
Conclusion: Docusate sodium solution is a more effective ceruminolytic than
triethanolamine polypeptide, allowing complete or partial visualization of
the tympanic membrane in most patients after a single application when fol
lowed with irrigation. Use of docusate sodium as a ceruminolytic should be
encouraged, particularly in children.