Treatment of canine asthma by high selective vagotomy

Abstract

This study evaluated the effect of high selective bilateral vagotomy of hilus pulmonis with video-assisted thoracoscopy on asthma. Eight dogs with skin sensitive to Ascaris suum antigens were randomly divided into groups A and B. Asthma was induced by aerosol inhalation of A suum antigens. Respiratory rate and peak airway pressure were significantly increased (P<.05) in both groups. Dynamic compliance was dramatically increased (P<.05) in both groups. Two days later, bilateral vagotomy of hilus pulmonis under thoracoscopic guidance was performed on dogs in group A; dogs in group B underwent bilateral sham vagotomy plus thoracoscopy. Five days after treatment, all dogs had rechallenge with a second aerosol inhalation. Dogs in group A did not show typical asthmatic symptoms, and no significant changes were found in respiratory rate, peak airway pressure, and dynamic compliance (P > .05). Dogs in group B still had typical symptoms, and respiratory rate and peak airway pressure were increased and dynamic compliance decreased significantly (P<.05 for all). Significant differences in respiratory rate, peak airway pressure, and dynamic compliance were observed between groups. Moreover, inflammatory cells in the lungs and bronchoalveolar lavage fluid of group A were dramatically reduced relative to group B (P<.05). There were no significant changes in heart rate and mean arterial pressure after vagotomy, indicating that vagotomy did not affect the cardiac plexus of vagus. High selective bilateral vagotomy of hilus pulmonis with thoracoscope can effectively control asthma in dogs.