A Multiparametric Acoustic and Self-Perceptual Measure of Laryngeal Hydrations in Speech-Language Pathologists: A Preliminary Longitudinal Investigation.

Abstract

Purpose: Speech-language pathologists (SLPs) work with individuals with communication disorders. Their work can strain their voice, resulting in dysphonia, adversely affecting their career and quality of life. Laryngeal hydration can prevent vocal damage and improve vocal performance in SLPs. However, there is limited research on the effects of laryngeal hydration in SLPs using longitudinal studies. Hence, the present study aims to assess the longitudinal impact of laryngeal hydration in SLPs using multiparametric acoustic and self-perceptual measures.

Method: The research method lasted for 6 consecutive days, with each day lasting 2-3 hours for each participant. Ten SLPs, aged 18-30 years, were recruited. On alternate days, laryngeal hydration treatment (systemic, surface, and combined hydration) was given while participants performed vocal loading tasks. Prerecording and postrecording of the Acoustic Voice Quality Index (AVQI) and its consistent parameters (smoothed cepstral peak prominence [CPPs], harmonics-to-noise ratio [HNR], shimmer%, shimmer local, long-term average spectrum [LTAS] slope, and LTAS tilt) and self-perceptual measures (perceived phonatory effort [PPE], perceived vocal tiredness [PVT]) were taken. Kruskal-Wallis test and the Wilcoxon signed-rank test were used to assess vocal changes in SLPs with laryngeal hydration.

Results: No significant differences in overall AVQI scores were found between pretests and posttests for all types of laryngeal hydration treatment. However, there was a significant increase in CPPs and the LTAS slope for combined hydration and a decrease in HNR with an increase in shimmer local for systemic hydration in the posttest compared with the pretest. Only systemic hydration in the posttest showed a rise in PPE and PVT compared with the pretest, compared with surface and combined hydration.

Conclusion: Voice outcome measures of the present study demonstrated the immediate beneficial effects of surface hydration and combined hydration in SLPs by preserving voice quality during vocal loading. Systemic hydration had less of an immediate impact on voice quality. This study suggests empirical evidence for laryngeal hydration, which can enhance vocal performance and preserve voice quality in SLPs.