Anesthesia Case of the Month

摘要

A 12-year-old spayed female Staffordshire Terrier mixed breed weighing 33.6 kg (74.0 lb) was evaluated for removal of 2 subcutaneous masses over the left flank and medial aspect of the left tarsus. Previously, cytologic examination of fine-needle aspirates had tentatively identified the masses as spindle cell tumors. The patient had a long history (> 2 years) of respiratory tract disease characterized clinically by intermittent coughing with occasional exercise intolerance and tachypnea. Serial radiography revealed a progressive, moderate-to-severe, diffuse bronchointerstitial pattern consistent with chronic allergic or idiopathic bronchitis or possibly fibrosis secondary to previous infectious disease (Figure 1). Clinical improvement was noted withadministration of fluticasone propionate (13.1 mug/kg [5.9 mug/lb], by inhalation, q 12 h) and theophylline (8.9 mg/kg [3.9 mg/lb], PO, q 12 h).Echocardiography had been performed to rule out pulmonary hypertension and had revealed aortic root dilatation, severe left ventricular hypertrophy, and a small amount of tricuspid regurgitation. Pulmonary hypertension was judged unlikely on the basis ofpulmonary arterial pressures estimated by use of spectral Doppler ultrasonographic interrogation of peak tricuspid regurgitation velocity as well as the lack of right ventricular hypertrophy or pulmonary arterial enlargement. Mild systemic hypertension(systolic arterial pressure, 160 to 180 mm Hg) was confirmed by means of repeated Doppler ultrasonographic monitoring, and amlodipine (0.15 mg/kg [0.07 mg/lb], PO, q 12 h) and atenolol (0.19 mg/kg [0.08 mg/lb], PO, q 12 h) were prescribed. The dilatationof the aortic root was consistent with systemic hypertension, but the degree of left ventricular hypertrophy was judged to be disproportionate in nature. The findings were consistent during repeated echocardiography and were considered unrelated to thepulmonary disease.