In this research necropsy findings retrieved from archives of the Department of Veterinary Pathology at the Faculty of Veterinary Medicine Zagreb were analyzed. Data covered a four year period from 2014 to 2018 in which necropsy findings of animals that died in 24 hours perianesthetic period were analyzed to determine the most common causes of death. Results showed that the greatest number of causes of death, with established underlying disease, belongs to cardiac lesions with a focus on cardiomyopathy, which was established in 60% of cases. Also, in 38% of cases, the underlying disease that caused death was not established and the cause was specified as cardiorespiratory collapse, that is, insufficiency of the heart and lungs with unknown cause. Due to the lack of toxicological analysis, it was not possible to determine whether the cause was an incorrect dosage of certain drugs. In other cases, respiratory tract lesions in cats and systemic diseases were established, in which disseminated intravascular coagulation was established in the greatest number of animals, including dogs, cats and a ferret. Multidisciplinary review of perianesthetic death cases which includes pathologists, surgeons and anesthesiologists, could provide additional insight into the causes of deaths in animals in this period.