Master's student Institute of Veterinary Clinical Science, School of Veterinary Medicine, National Taiwan University Taipei, Taipei, Taiwan (Republic of China)
Existing veterinary literature on sleep-related breathing disorders (SRBDs) focuses almost exclusively on brachycephalic airway syndrome, leaving SRBDs in miniature breeds under-recognized.
Objectives
To characterize the clinical presentation, polysomnographic features, comorbidities, and treatment outcomes of miniature dogs with SRBDs, and to explore potential underlying etiologies.
Animals
Eleven client-owned miniature dogs (9 Chihuahuas and 2 Maltese) evaluated for suspected SRBDs.
Methods
Prospective observational case series. Whole-body barometric plethysmography (WBBP)-based polysomnography (PSG) was performed in all dogs, and their medical records were reviewed.
Results
All dogs exhibited paroxysmal, stertorous, and effortful breathing during sleep; however, over half (6/11, 54.5%) showed no abnormal respiratory pattern when awake. Sleep-related collapse following arousal occurred in 72% (8/11). Mean age at onset was 10.3 years (range 5-14 years). WBBP-based PSG findings were consistent with obstructive sleep apnea (OSA) and sleep-related hypoxemia described in humans. All dogs had at least one comorbidity: lower airway (4/11, 36.4%), gastrointestinal (3/11, 27.3%), cardiovascular (10/11, 90.9%), and endocrine disorders (3/11, 27.3%). Treatment included ondansetron, adjunctive respiratory therapies , targeted management of comorbidities, and environmental modification when indicated. Of the 9 dogs with follow-up (26-686 days), 3 (33.3%) achieved complete remission and 6 (66.7%) had partial but clinically meaningful improvement.
Conclusions and clinical importance
SRBDs are an underdiagnosed cause of sleep disturbance and collapse in middle- to old-aged miniature dogs, especially those without obvious upper airway obstruction during wakefulness. WBBP-based PSG enables objective identification of OSA-like events in this population. Multimodal therapy appears effective in improving sleep quality and reducing collapse episodes.
Learning Objectives:
Upon completion, participants will be able to recognize the clinical presentation of sleep-related breathing disorders, especially sleep-related collapse, in miniature dogs, particularly in patients without apparent respiratory abnormalities during wakefulness.
Upon completion, participants will be able to differentiate sleep-related breathing disorders in miniature dogs from brachycephalic airway syndrome based on clinical characteristics and presumed pathophysiology.
Upon completion, participants will be able to interpret whole-body barometric plethysmography-based polysomnographic findings to identify and characterize sleep-related breathing disorders in canine patients.
Upon completion, participants will be able to formulate diagnostic and management approaches for miniature dogs with sleep-related breathing disorders based on clinical and polysomnographic assessment.
.jpg "Li-Chi Lin, DVM photo")