Why cats need breathing machines and how they recover

Abstract

OBJECTIVE: To determine indications for and outcomes of positive-pressure ventilation (PPV) in cats, document ventilator management, and identify factors associated with outcome. DESIGN: Retrospective study. ANIMALS: 53 cats that underwent PPV. PROCEDURE: Information on signalment, history, concurrent diseases, clinical findings, results of venous blood gas analyses and clinicopathologic testing, treatment, ventilator settings, and outcome was retrieved from the medical records. Data for cats that survived were compared with data for cats that died or were euthanatized while undergoing PPV RESULTS: PPV was initiated for management of respiratory failure (36 cats [68%]), cardiac arrest (9 [17%]), neurologic impairment (6 [11%]), and nonresponsive hypotension (2 [4%]). Eight cats (15%) survived, 19 (36%) died, and 26 (49%) were euthanatized while undergoing PPV. Cats that survived had a longer duration of ventilation than did those that died or were euthanatized and had a significantly higher incidence of ventilator-associated pneumonia. Signalment and ventilator settings were not associated with outcome. Cats that had no clinical evidence of pulmonary disease but required PPV because of primary neurologic disease had a higher survival rate (2/6) than did cats that required PPV because of respiratory failure (5/36), cardiac arrest (1/9), or nonresponsive hypotension (0/2). CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that the survival rate for cats requiring PPV may be lower than reported survival rates for dogs. Death was attributable to progressive respiratory failure, non-responsive hypotension, kidney failure, or neurologic impairment.