Videofluoroscopic swallow study abnormalities identify aerodigestive disorders in dogs with respiratory disease versus healthy controls

Abstract

Aerodigestive diseases (AeroD) pathologically link respiratory and alimentary tracts. Dogs with respiratory signs lacking dysphagia, vomiting, or regurgitation typically do not undergo diagnostic testing that identifies comorbid alimentary disease. A videofluoroscopic swallow study (VFSS) identifies defects in swallowing, reflux, and aspiration. We hypothesized that dogs with respiratory and no alimentary disease (RESP) would have significantly more abnormal VFSS metrics versus controls (CON). We hypothesized RESP dogs with pulmonary parenchymal disease would have more reflux and higher penetration-aspiration score (PAS) than those with airway disease. Client-owned dogs: RESP (n=45) and CON (n=15) groups. Prospectively, all dogs underwent VFSS. The RESP dogs had advanced respiratory diagnostic testing. Eight subjective and 3 objective VFSS metrics (pharyngeal constriction ratio [PCR], PAS, and esophageal transit time [ETT]) were assessed. Fisher's exact test compared differences between groups (presence or absence of VFSS abnormalities). The Mann-Whitney rank sum test was used to compare PCR and PAS. Subjective VFSS abnormalities were present in 34/45 (75%) RESP and 2/15 (13%) CON dogs, with RESP dogs significantly more likely to have VFSS abnormalities (P=.01). No difference in PCR was found between groups. Pathologic PAS was more common in RESP than CON dogs (P=.03). The RESP dogs with airway disease had higher PAS than CON dogs (P=.01) but not RESP dogs with parenchymal disease (P=.25). Most (75%) RESP dogs had VFSS abnormalities, emphasizing that AeroD are common. The VFSS has value in diagnostic evaluation of respiratory disease.