Background: Sedation is frequently required in dogs for diagnostic workups and patient safety. Yet, sedation affects serum cortisol levels; butorphanol elevates cortisol, while dexmedetomidine reduces it dose dependently. Understanding the duration of sedation’s impact on cortisol concentration is important. Hypothesis/
Objectives: To evaluate baseline serum cortisol at time 0 and 6-hours post-sedation with saline (0.5 mL IV), butorphanol (0.3mg/kg) and combination of butorphanol and dexmedetomidine (0.3mg/kg and 5mcg/kg IV, respectively). Additionally, to compare post-adrenocorticotrophic hormone (ACTH) cortisol concentration at 7 hours after these sedation protocols. Animals: 12 healthy, castrated, colony beagles
Methods: Randomized, blinded, controlled, repeated-measure crossover design with a one-week washout between treatments. Serum cortisol was measured at time 0 and 6-hours post-sedation with saline, butorphanol, or combination butorphanol and dexmedetomidine. An ACTH-stimulation test was performed at 6-hours post-sedation. A mixed model analysis with treatment and time as fixed factors was utilized for significance.
Results: Mean serum cortisol concentration was not significantly different at time 0 and 6-hours following saline (1.47; 0.91 µg/dL, respectively; p=0.69), butorphanol (0.9; 0.95 µg/dL, respectively; p=0.29), and combination (0.96; 1.62 µg/dL, respectively; p=0.57). There was no significant difference in post-ACTH cortisol for saline, butorphanol, or combination treatment (8; 8.66; 8.46 µg/dL, respectively; p=.841)Conclusions and clinical importance: In healthy dogs following sedation with the aforementioned protocols, cortisol concentration returns to baseline by 6 hours. An ACTH stimulation test started 6-hours post-sedation is not affected by these drug protocols, which allows for same-day sedation. Additional studies are needed in dogs with adrenal dysfunction.
