Thoracic Ultrasound: A Method for the Work-Up in Dogs and Cats with Acute Dyspnea

Diagnosing pleuro-pulmonary diseases causing acute dyspnea is a daily challenge for radiologists working in intensive care units. Ultrasonography for non-cardiac intrathoracic structures has recently been used as a first responder's diagnostic method. The aim of this paper is to study the diagnostic accuracy of pleural and lung ultrasound (PLUS) exploiting the experience gained in the use of ultrasound along with X-rays performed on dogs and cats in emergency care. From January 2015 to December 2016 we considered 68 animals (50 dogs and 18 cats) with acute dyspnea, admitted to the “Mario Modenato” Teaching Hospital of the University of Pisa and subjected to thorax ultrasound and X-ray examination. We obtained the final diagnosis of diaphragmatic hernia (5 cases), pleural effusion (28), pneumothorax (6), lung consolidation (8), alveolar-interstitial syndrome (19), and tracheal rupture (2). Ultrasound diagnosis was carried out by directly visualizing the pathology in the case of a diaphragmatic hernia or pleural effusion, and by visualizing the artifacts that altered the physiologic ultrasound semeiotics, as in the case of pneumothorax, alveolar-interstitial syndrome by cardiogenic pulmonary edema, poisoning anticoagulants, acute respiratory distress syndrome (ARDS), pulmonary contusion and alveolar consolidation by aspiration pneumonia. The ultrasound allowed us to identify the disease and its location in most of the cases. The sensitivity and specificity were both 100% for pleural diseases and alveolar consolidation, 100% and between 87.5-95% for the alveolar-interstitial syndrome, respectively. The thoracic ultrasound examination is characterized by good sensitivity, rapid execution, and repeatability, a factor that make it an ideal tool for the management of patients with acute dyspnea; it allows to differentiate cardiogenic to non-cardiogenic edema. In addition, it could be used as an imaging method for clinical and therapeutic follow up of patients, and it reduces exposure to ionizing radiations.