A Retrospective Study on Canine and Feline Mortality during Anaesthesia at a University Clinic in Greece

SIMPLE SUMMARY: Anaesthesia-related mortality is a critical topic in the field of medicine that should occasionally be reassessed, as it provides information on the quality of anaesthesia care and can be used as an indicator of safety. On top of this, various critical points in the peri-anaesthetic management of the patient can be determined to improve standard of care and avoid future complications. This study investigated cardiac arrest and death rates in dogs and cats during anaesthesia, in a Greek veterinary academic institution and assessed certain factors that may contribute to a higher mortality rate. It was concluded that cats have a higher risk of death than dogs with the current anaesthesia practices, and that more caution must be taken in the peri-anaesthetic management of this species. ABSTRACT: This retrospective cohort study investigated the mortality rate during anaesthesia and possible contributing factors in canine and feline population in an academic institution in Greece. Data on 1187 dogs and 250 cats which underwent general anaesthesia from 1 January 2018 to 31 December 2019 at the Veterinary Faculty of the Aristotle University of Thessaloniki were analysed regarding cardiac arrest and mortality. In dogs, the rate of cardiac arrest was 1.1% and the rate of death was 0.6%. In cats, these rates were 2.8% and 0.8%, respectively. The mortality rate in healthy/mild disease (ASA I-II) dogs was 0.1% and in cats was 0.5%. Sick (ASA III-V) dogs exhibited a death rate of 2.6%, while sick cats had a rate of 2.2%. In dogs, ASA status had a positive association with cardiac arrest and mortality, with sick dogs being 23 times more likely to suffer cardiac arrest and 24.5 times more likely to die than healthy/mild disease ones. Other factors associated with cardiac arrest and mortality were the anaesthetic protocol and the use of inotropes. In cats, premedication and inotropic support were related to cardiac arrest and death. Feline anaesthesia involves higher risk, and requires greater vigilance in peri-anaesthetic management than dogs.