Upper Airway Sensory Testing in Dysphagia - Implications for Clinical Practice and Future Research Directions

Adequate upper airway (oral, pharyngeal and laryngeal) sensation is crucial for safe and efficient swallowing and airway protection. Despite its importance, methods of upper airway sensory testing for individuals with dysphagia remain poorly defined. The aim of this study was to summarise and appraise current methods of upper airway sensory testing to inform dysphagia clinical practice and future research directions. A systematic review was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Studies that reported a method of upper airway sensory testing in individuals with dysphagia were included. Of the 1187 studies identified and screened, 54 met the inclusion criteria. Four types of upper airway sensory testing were reported: Flexible Endoscopic Evaluation of Swallowing with Sensory Testing (n = 31), Cough Reflex Testing (n = 22), Gag Reflex Testing (n = 5) and Gustatory (taste) Testing (n = 2). Indeterminate "tests of sensory function" (n = 2) were also reported. Variability in methods was evident across studies and reporting was insufficient for reliable replication. This review provides a comprehensive overview of methods of upper airway sensory testing in the dysphagia literature for dysphagia clinicians and researchers. The results indicate a need to develop a valid and reliable upper airway sensory testing protocol for individuals with dysphagia to improve assessment and targeted treatments.