Comparison of phenol with tetracaine base and four quadrant injection methods for tympanic membrane anesthesia

Abstract

Objectives: To compare three methods used for anesthesia of eardrum including four quadrant canal injection, tetracaine based isopropyl alcohol, and phenol application.Methods: This investigation included 32 patients between the ages of 18 and 71 (mean 30.5) who had been planned to undergo myringotomy with or without ventilation tube replacement for various reasons. The patients were divided into two groups. In the first group of patients, the left eardrums were applied with phenol whereas right eardrums were anesthetized with four quadrant injection. In the second group, the left eardrums were applied with phenol whereas right eardrums were anesthetized with tetracaine based isopropyl alcohol. A questionnaire was administered in which patients were asked to score their pains during anesthesia and surgical procedure.Results: The main pain scores during four quadrant injection were found to be higher than scores during phenol application. No significant difference was found between two methods with regard to pain scores during surgical procedures. No significant difference was found between phenol and tetracaine base application with regard to pain scores during anesthesia. However, the pain scores during surgical procedures following tetracaine base application were found to be higher than scores of phenol application.Conclusion: Phenol application provides faster and more reliable anesthesia of eardrum compared with four quadrant injection and tetracaine base application.

Keywords

• eardrum
• anesthesia
• phenol