The Volume-Viscosity Swallow Test for Clinical Screening of Dysphagia and Aspiration

Abstract

Oropharyngeal dysphagia (OD) is a major complaint among many patients with neurological diseases and in the elderly, but is often underdiagnosed. The volume-viscosity swallow test (V-VST) is a bedside method to screen patients for dysphagia. The V-VST was designed to identify clinical signs of impaired efficacy (labial seal, oral and pharyngeal residue, and piecemeal deglutition) and impaired safety of swallow (voice changes, cough and decrease in oxygen saturation ≥3%). It starts with nectar viscosity and increasing bolus volume, then liquid and finally pudding viscosity in a progression of increasing difficulty to protect patients from aspiration. The V-VST allows quick, safe and accurate screening for OD in hospitalized and independently living patients with multiple etiologies. The V-VST presents a sensitivity of 88.2% and a specificity of 64.7% to detect clinical signs of impaired safety of swallow (aspiration or penetration). The test takes 5-10 min to complete. The V-VST is an excellent tool to screen patients for OD. It combines good psychometric properties, a detailed and easy protocol designed to protect safety of patients, and valid end points to evaluate safety and efficacy of swallowing and detect silent aspirations.