BILATERAL RECURRENT LARYNGEAL NEURECTOMY AS A MODEL FOR THE STUDY OF IDIOPATHIC CANINE LARYNGEAL PARALYSIS

The purposes of this study were to develop an experimental model of ca nine laryngeal paralysis that mimicked the naturally occurring disease and to document the upper airway changes produced, both clinically an d with pulmonary function testing. Ten dogs had bilateral recurrent la ryngeal neurectomy performed and were recovered from anesthesia. Tidal breathing flow-volume loop analysis and upper airway resistance measu rements were taken before and after the development of clinical laryng eal paralysis while dogs breathed room air and after the individual ad ministration of 2 respiratory stimulants. Clinical signs of laryngeal paralysis developed 38 days (median) following denervation. Although s ome variations were present, tidal breathing flow-volume loop analyses on room air, following denervation, were similar to those reported in naturally occurring cases. Upper airway resistance increased followin g denervation and was significantly increased with both respiratory st imulants. We concluded that bilateral recurrent laryngeal neurectomy r esulted in clinical signs and respiratory changes similar to those of idiopathic canine laryngeal paralysis.