IMPORTANT: The authors, reviewers, and editors of the material in the 2020 AAHA Anesthesia and Monitoring Guidelines for Dogs and Cats have made extensive efforts to ensure that treatments, drugs, and dosage regimens are accurate and conform to the standards accepted at the time of publication. However, constant changes in information resulting from continuing research and clinical experience, reasonable differences in opinions among experts, unique aspects of individual clinical situations, and the possibility of human error in preparing such an extensive text require that the veterinarian exercise individual judgment when making a clinical decision and, if necessary, consult and compare information from other sources. In particular, the veterinarian is advised to check the drug’s product insert before prescribing or administering it, especially if the drug is unfamiliar or is used infrequently.