Fulminant brachycephalic obstructive airway syndrome in a 3‐month‐old French bulldog

Abstract A 3‐month‐old, entire, female French bulldog (6.4 kg) presented in severe respiratory distress with hyperthermia and cyanosis. Laryngeal examination revealed severe obstruction by oedematous tissue, later confirmed as bilaterally everted laryngeal saccules; the airway was stabilised by tracheal intubation. Venous blood gas after intubation showed pH 7.37 and pCO 2 52 mmHg. Despite normalised SpO 2 (100%) and EtCO 2 (45 mmHg), sinus tachycardia persisted at 156–210 beats per minute. Echocardiography documented hyperdynamic systole with dynamic biventricular outflow obstruction but no congenital defects. Owners declined tracheostomy and definitive surgery; humane euthanasia was elected. Postmortem examination confirmed elongated soft palate, everted saccules, severe tracheal hypoplasia with fragmented cartilage rings, and mild lymphoplasmacytic pneumonia. Tracheal PCR yielded high Mycoplasma spp. load. Heart‐rate‐variability analysis supported compensatory tachycardia. This case illustrates that severe brachycephalic obstructive airway syndrome can cause fatal decompensation in very young brachycephalic puppies, with airway inflammation and heavy tracheal Mycoplasma colonisation representing possible contributing comorbidities.