Respiratory Disease in the Cat Lower Respiratory Tract

Dyspnoea, or difficulty in breathing, is relatively common in cats. It can result from
a decreased ventilatory capacity, or an increased ventilatory demand. Therefore, dyspnoea can result from both respiratory and non-respiratory causes. The first step in the investigation of dyspnoea is to determine whether or not it is due to non-respiratory causes, upper respiratory tract (URT) causes, lower respiratory tract (LRT) causes or pleural space disease. Therefore, it is important to ascertain whether or not the cat is displaying inspiratory, expiratory dyspnoea or tachypnoea. Inspiratory dyspnoea is most commonly associated with either pleural space disease, or URT causes, whereas LRT diseases commonly present with expiratory dyspnoea. Many of the non-respiratory causes of dyspnoea (ie: hyperthyroidism, metabolic acidosis, abdominal enlargement, hyperthermia, fear stress, pain) will present with tachypnoea. […]