Physical examination of the respiratory system

This article reviews the approach to a patient with respiratory distress, with a focus on clues obtained from the physical examination. Respiratory distress is a common reason for presentation of a companion animal to a veterinarian on an emergency basis, and thus the clinician should have a comfort level with the approach to these patients. Our discussion includes a basic review of respiratory pathophysiology and the differential diagnoses for hypoxemia. In the majority of cases, physical examination should allow localization of the cause of the respiratory problem to the upper airways, lower airways, pleural space, or pulmonary parenchyma. Such localization, coupled with signalment and historical clues, guides additional diagnostics and therapeutics based on the most likely differential diagnoses. Although managing a patient with respiratory distress can be challenging, a systematic approach such as the one presented here should ensure appropriate intervention in a timely fashion and maximize the chance of a good outcome.