Sounding out Dysphagia: Using a Digital Stethoscope to Assess Audiometric Differences in Swallowing

A clinical swallow evaluation (CSE) is a subjective exam with limited diagnostic accuracy. We hypothesize that audiometric data collected superficially can enhance the detection of swallowing dysfunction. This study examines audiometric differences between normal and dysfunctional swallows on Flexible Endoscopic Evaluation of Swallowing (FEES) using a digital stethoscope.

In this single-center prospective study, adult patients undergoing FEES for dysphagia had a digital stethoscope placed on the left neck. Audiometric data were analyzed by consistency and compared to Penetration-Aspiration Scale (PAS) and Yale Pharyngeal Residue Severity Rating Scale (YPS) scores.

Forty-nine patients with a total of 617 individual swallow events were included. Twenty-two patients (45%) had a PAS score of 1-2, 20 (41%) had a PAS score of 3-5, and 7 (14%) had a score of PAS 6-8. Multivariable analysis revealed significant differences in swallow duration (F = 4.65; p = 0.01), peak amplitude (F = 10.6; p < 0.0001), area under the curve (F = 6.13; p = 0.002), and median frequency (F = 8.52; p = 0.0002). Patients with PAS ≥ 3 had prolonged swallow (5.4 s versus 3.3 s, p < 0.0001), lower peak amplitudes (0.25 dB versus 0.32 dB; p < 0.001), and a lower median frequency (169.4 Hz versus 214.8 Hz; p < 0.0001) compared to those with PAS 1-2. Higher YPS scores (III-V) were associated with a longer swallow duration (5.5 s versus 3.5 s, p < 0.0001) and lower median frequency (158.1 Hz versus 221.1 Hz; p = 0.0005).

Audiometric data reveals significant differences in swallow duration, amplitude, and frequency in patients with swallow dysfunction. These findings suggest that audiometric analysis may serve as a valuable adjunct to the standard CSE.