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tvpjournal.com | November/December 2015 | ToDay's VeTeriNary PracTice aPProach To resPiraTory DisTress Peer reviewed 53 Managing dogs and cats in respiratory distress is a multifaceted effort that involves stabilizing patients prior to determining a defnitive diagnosis. Fortunately, respiratory distress—no matter what the cause—requires somewhat standardized interventions during initial stabilization. INITIAL STABILIZATION One of the benefits of initial stabilization is that it provides the practitioner time to consider the appropriate diagnostic and subsequent therapeutic approach. Oxygen Supplementation Initial stabilization of a patient in respiratory distress generally involves provision of oxygen supplementation, with or without patient sedation. • The most common type of oxygen supplementation provided is use of an oxygen cage with a high fraction of inspired oxygen (FiO 2 ) (eg, 40%–60%); a face mask or flow-by oxygen from a hose can also be used. • In more extreme cases, animals in respiratory distress may require emergency intubation, higher FiO 2 (eg, 100%), and provision of positive pressure ventilation in order to provide adequate respiratory stabilization. • Particularly in cases of upper airway obstruction, the practitioner may need to ensure a patent airway by intubation or tracheostomy (if oral intubation is not possible). Sedation Sedation with careful monitoring and, if necessary, intubation and ventilation can be extremely useful in animals that have become anxious due to hypoxemia and/or hypercapnia. In some patients, especially dogs with upper airway obstruction, stabilization may require sedating the animal by administering some form of anesthetic induction agent; then clearing the oral cavity of obstructing material (eg, secretions or foreign material in a choking animal) prior to intubation or tracheostomy. Cooling Measures Animals with upper airway obstruction, such as those with laryngeal paralysis, may become hyperthermic due to the increased work of breathing. Because of the airway obstruction, these animals are unable to effectively pant, resulting in inability to thermoregulate and dissipate heat. As such, cooling hyperthermic patients in respiratory distress is an important component of initial stabilization, and can be accomplished by: • Administering room temperature IV fluids • Covering the patient with wet towels • Putting a fan on the patient • Applying alcohol to the axilla, inguinal area, and feet. Active cooling should stop once the patient's temperature reaches 103°F to avoid precipitating hypothermia. Thoracocentesis Initial stabilization may also include thoracocentesis, if severe respiratory distress is secondary to pleural space disease, such as pneumothorax or pleural effusion. INITIAL DIAGNOSTIC APPROACH Diagnostic approach to a patient in respiratory distress should consider the patient's signalment and history as well as the broad anatomic differential diagnoses of dyspnea (Table 1, page 54). Signalment Clues in the patient's signalment are common. For example: • Upper airway obstruction due to brachycephalic airway disease is a common cause of respiratory distress in brachycephalic dogs, such as English bulldogs. • Cardiogenic pulmonary edema is a common cause of respiratory distress in small breed dogs with chronic valvular disease (eg, mitral endocardiosis), such as Cavalier King Charles spaniels. • Lower airway obstruction associated with asthma is a common cause of respiratory distress in cats, with certain breeds, such as the Siamese, overrepresented. Approach to Respiratory Distress in Dogs & Cats Claire R. Sharp, BSc, BVMS (Hons), MS, CMAVA, Diplomate ACVECC Tufts University Minimizing Stress Dogs and cats with respiratory distress are often fragile and can decompensate rapidly. Initial evaluation should be performed rapidly, with minimal stress to the patient. Often, one of the best frst steps is to place the animal in an oxygen cage and allow it to relax, considering it has usually been through a stressful car ride and changed environments (home to car to clinic) that can exacerbate distress. Peer Reviewed 53