# Comorbidity and Procedural Factors Associated With Auditory Brainstem Response Outcomes in Children Under Anesthesia

## TL;DR

This study found that children's heart and lung conditions, along with the type of medical procedure, more strongly affect hearing test results than the type of anesthesia used.

## Contribution

The study identifies comorbidities and procedural context as stronger predictors of ABR outcomes than anesthesia type in children.

## Key findings

- Children with cardiac or respiratory comorbidities were significantly more likely to show hearing loss in ABR tests.
- Combined procedures were associated with a higher likelihood of normal hearing outcomes compared to standalone ABR testing.
- Anesthesia type (propofol vs. sevoflurane) did not significantly affect ABR thresholds after adjusting for patient health factors.

## Abstract

Introduction

We aim to evaluate the influence of patient comorbidities and procedural context (standalone vs. combined procedures) on auditory brainstem response (ABR) outcomes in children and to explore whether anesthesia type (propofol vs. sevoflurane) contributes to differences in hearing thresholds.

Methods

A retrospective chart review was conducted of 403 pediatric patients who underwent sedated ABR testing between October 2020 and 2023 at a tertiary children’s hospital. Demographic, anesthetic, and clinical variables, including neurological, cardiac, and respiratory comorbidities, were analyzed. Hearing outcomes were categorized as normal versus any hearing loss across click and tone-burst frequencies. Logistic regression analyses examined associations between hearing loss, anesthesia type, comorbidities, and procedural context, adjusting for American Society of Anesthesiologists (ASA) classification.

Results

No significant association was found between anesthesia type and ABR thresholds after adjusting for ASA class. In contrast, children with cardiac (36% vs. 53%; p=0.008) or respiratory (40% vs. 57%; p=0.013) comorbidities were significantly more likely to exhibit hearing loss. Patients undergoing combined procedures were more likely to have normal hearing than those having standalone ABR testing (69% vs. 60%; p=0.006). Neurological comorbidities showed no significant association.

Conclusion

Comorbidities, particularly cardiac and respiratory conditions, and procedural context were stronger predictors of ABR outcomes than anesthesia type. These findings suggest anesthetic choice may not independently alter ABR thresholds, emphasizing the importance of considering patient health status and procedural setting when interpreting pediatric ABR results.