Work

Comparison of fentanyl and alfentanil in combination with atropine for premedication of dogs undergoing radiotherapy

Year: 2025

Type: article

Abstract: Objective To evaluate the effects of two opioid-based premedication protocols on propofol requirement, time to recovery, and occurrence of post-anaesthetic vocalization, paddling, nystagmus and dysphoria in dogs anaesthetised for radiotherapy. Study design Blinded, randomized, crossover clinical study. Animals A total of 22 client-owned dogs, each serving as their own control. Methods Dogs were randomly assigned to one of two intravenous premedication protocols on their first radiotherapy session, and the other on their second session. Premedication consisted of atropine (10 μg kg -1 ) mixed with equipotent doses of either alfentanil (10 μg kg -1 , group AA) or fentanyl (2.5 μg kg -1 , group FA), followed by propofol induction and maintenance with sevoflurane in oxygen. Cardiorespiratory variables and observation of dysphoria and nystagmus were recorded after premedication and during recovery. Time elapsed from discontinuation of sevoflurane to tracheal extubation, sternal position and walking were also recorded (minutes). Results The proportion of dogs showing dysphoria and nystagmus was not different between treatments at any time point. With both treatments, heart rate (mean ± standard deviation) decreased after premedication (82 ± 27 and 93 ± 27 beats minute -1 in groups AA and FA, respectively) compared to baseline (117 ± 23 and 112 ± 26 beats minute -1 in groups AA and FA, respectively; p < 0.001). Propofol dose did not differ between treatments (3.8 ± 1.7 and 4.3 ± 1.3 mg kg -1 in groups AA and FA, respectively). Time to extubation was shorter with treatment AA (5.3 ± 2.1 minutes) compared with treatment FA (6.2 ± 2.3 minutes; p = 0.049), while time to sternal recumbency and walking did not differ between treatments. Conclusions and clinical relevance Since the two protocols produced comparable clinical effects and were both found suitable for dogs undergoing repeated radiotherapy, fentanyl is recommended over alfentanil in countries where it is licensed.

Source: Veterinary Anaesthesia and Analgesia

DOI: 10.1016/j.vaa.2025.06.004

Authors: Giovanni Franchino, Adam Shuttleworth, Pietro Loddo, Chiara Adami

Institution: University of Cambridge

Language: English

Topic: Veterinary Pharmacology and Anesthesia

Subfield: Small Animals

Field: Veterinary

Domain: Health Sciences

SDG: Good health and well-being

Open Access status: hybrid

Estimated APC paid: $3,000