Ultrasound and x-ray examination at lung edema of domestic cat

Abstract

The aim: This study aims to determine the diagnostic value of lung ultrasound compared with radiography for respiratory distress in cats.
 Materials and methods: The database of the veterinary center was analyzed. 130 animals diagnosed with pulmonary edema were selected. The lungs of sick cats were examined ultrasonographically; The line was counted in 4 anatomical sections on each hemithorax. A site was evaluated as positive when > 3 "B-lines" were detected. Animal treatment protocols were studied to clarify the final diagnosis (reference standard), and the sensitivity and specificity of lung ultrasound and chest X-ray for the diagnosis of pulmonary edema were calculated.
 Result: Cats with a final diagnosis of cardiogenic pulmonary edema had a greater number of positive areas on ultrasound than those, in which respiratory distress was caused by non-cardiogenic pulmonary edema. The overall sensitivity and specificity of US for the diagnosis of pulmonary edema were 87 % and 89 %, respectively, and these values were similar to those of chest radiography (85 % and 86 %, respectively). The use of ultrasound led to a false diagnosis of cardiogenic pulmonary edema (ie, a false-positive result) in animals with diffuse interstitial or alveolar changes.
 Conclusions: Ultrasound examination of the lungs in cats with respiratory distress syndrome is a promising diagnostic method. Emergency diagnosis of pulmonary edema in cats is difficult, especially in patients with severe shortness of breath, and limits the diagnostic evaluation. Chest x-rays are considered the standard diagnostic test, but the results are sometimes ambiguous and the process of obtaining the x-rays can increase respiratory distress in the animal.
 According to the results of the study, it was established, that ultrasound examination of the lungs can be used to differentiate the causes of shortness of breath (cardiogenic and non-cardiogenic) with sufficiently high sensitivity and specificity and less influence of the iatrogenic factor on the development of respiratory distress in cats, compared to chest radiography