Evaluation of age and American Society of Anesthesiologists (ASA) physical status as risk factors for perianesthetic morbidity and mortality in the cat

Objective: To evaluate age and American Society of Anesthesiologists (ASA) physical status as risk factors for perianesthetic morbidity/mortality in cats. Design: Prospective cohort study. Setting: Institution teaching hospital. Animals: 138 cats ≥ 6 months of age that received inhalation anesthesia for ≥ 30 min Interventions: Observations were made during the 24 h post‐anesthetic period. Measurements and main results: Sixty‐one females and 77 males were included. Serious perianesthetic complications occurred in 15 cats (15/138; 11%), including cardiopulmonary arrest in 3 cats (3/138; 2%), and death or euthanasia in 7 cats (7/138; 5%). Age was not a factor in establishing risk for developing serious or minor perianesthetic complications in the cats in this study. However, ASA status was a risk factor. Cats having an ASA status of 3 or more were nearly 4 times as likely to develop serious perianesthetic complications, even when accounting for the significant confounding effects of anesthesia duration. Conclusions: ASA status, but not age, was a risk factor for the development of serious or minor perianesthetic complications in the 138 cats included in this study.