Pediatric hearing assessment by auditory brainstem response in the operating room.

OBJECTIVES

To investigate the factors contributing to the discrepancies between auditory brainstem response (ABR) thresholds obtained in the operating room (OR) and hearing outcomes obtained in the follow-up period and to explore the benefits and limitations of performing ABR in the OR.

METHODS

A retrospective review study was conducted in a pediatric tertiary care facility. A total of 116 patients were identified with complete records, including OR-ABR results, medical examination and surgical procedure notes, and follow-up medical/audiological evaluation. Patients were divided into three groups: (1) 58 patients with middle ear effusion underwent myringotomy and tube placement, (2) 12 patients underwent myringotomy without tube placement, (3) 46 patients underwent ear examination only without effusion found. OR-ABR results were compared to audiological follow-up evaluations and analyzed for each group.

RESULTS

In patients with middle ear effusion and tube placement, the average threshold difference between OR-ABR and follow-up audiological evaluation was 9.7 dB (± 12.7), with highest discrepancy of 45 dB. On the other hand, in patients with dry ears and/or no tube placement, the average threshold difference was only 3.8 dB (± 8.6). Moreover, the discrepancy was more prominent in patients with mucoid effusion and larger at lower frequency, i.e., 1000 Hz.

CONCLUSIONS

The hearing thresholds estimated by ABR testing in the OR can be elevated and follow-up hearing evaluation after tube placement is needed. While ABR testing is valuable in the assessment of pediatric patients, especially for children who are difficult-to-test or have complicated medical conditions, caution should be taken when interpreting OR-ABR results.