Factors Impacting Quality of Anesthetic Recovery in Dogs

In the Literature

Jones H, Robson K, Maddox T, Alderson B. Incidence of and risk factors for poor recovery quality in dogs recovering from general anaesthesia—a prospective case control study. Vet Anaesth Analg. 2024;51(3):227-234. doi:10.1016/j.vaa 2023.12.002

The Research …

Poor-quality, rough recoveries in veterinary anesthesia increase risk for injury in patients and staff. Vocalization, agitation, nonpurposeful movement, thrashing, and rolling are frequently observed during difficult recoveries, similar to emergence delirium in humans that occurs transiently following anesthesia and is characterized by irritation, dissociation, and lack of response to consoling measures.¹ Previous evaluation of quality of recovery (QOR) in dogs has focused on the role of specific induction agents or drug combinations without identifying patient-specific risk factors.^2,3

In this study, QOR was evaluated using a simple descriptive scale in dogs (n = 247) undergoing general anesthesia for surgical, imaging, or diagnostic procedures. One-third (29.1%) of dogs experienced poor QOR, with 55.5% of those requiring sedation to control recovery. Alpha-2 agonists (ie, medetomidine, dexmedetomidine) were used most frequently for recovery sedation, and acepromazine, ketamine, methadone, and propofol were used rarely (1-2 dogs each). Ten dogs required >1 sedative/analgesic.

Dogs with American Society of Anesthesiologists (ASA) physical status classification III or higher had decreased incidence of poor QOR. Dogs that received multiple inhalant agents during anesthesia had increased incidence of poor QOR compared with dogs that received total intravenous anesthesia. Occurrence of poor QOR did not differ between painful and nonpainful procedures, and no evidence of breed-specific differences was found.

… The Takeaways

Key pearls to put into practice:

• Poor QOR was more likely in patients with ASA status I or II that are overall healthy and more vigorous than patients with higher ASA status. ASA status should be considered when need for sedation is determined at the beginning of recovery. Pre-emptive sedation should reduce incidence of emergence delirium. Alpha-2 agonists were the most commonly used sedatives to manage poor recovery in this study and are generally considered reliable and fast acting, allowing rapid control of poor recovery behaviors.

• Patients with ASA status III or higher experienced poor QOR less frequently than patients with ASA status I or II but have longer recoveries and require more attention to maintenance of ventilation, oxygenation, blood pressure, and temperature, regardless of whether emergence delirium is present.

• QOR did not differ between painful and nonpainful procedures; however, pain and emergence delirium are often difficult to differentiate, and the recovery scale used in this study was not validated. The role of pre-emptive analgesia in QOR was not evaluated but is important for patients undergoing painful procedures. Failure to adequately and pre-emptively manage pain likely contributes to poor QOR.