Profound hypokalemia causing respiratory failure in a cat with hyperaldosteronism

Objective: Description of acute respiratory failure in a cat due to profound hypokalemia associated with primary hyperaldosteronism. Case summary: A cat was presented with weakness and paraparesis that deteriorated rapidly into acute ventilatory failure. The serum potassium concentration declined despite intravenous fluid therapy. Positive pressure ventilation was required to support ventilatory function. A functional adrenocortical adenoma was found at necropsy in conjunction with a serum aldosterone concentration of greater than 3329 pmol/L. New or unique information provided: Respiratory failure secondary to profound hypokalemia is a rare, although recognized, condition. There are few reports that focus on this aspect of respiratory failure in the veterinary literature and primary hyperaldosteronism has not been reported as a cause of respiratory failure in cats.