Cardiovascular tolerance of intravenous lidocaine in broiler chickens (Gallus gallus domesticus) anesthetized with isoflurane |
| |
| Authors: | João Brandão Anderson F da Cunha Bruno Pypendop Rhett Stout Javier Nevarez Thomas N Tully Jr |
| |
| Institution: | 1. Department of Veterinary Clinical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA, USA;2. Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis, CA, USA;3. Department of Laboratory Animal Medicine, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA, USA |
| |
| Abstract: | ObjectiveTo determine the cardiovascular effects of lidocaine infused intravenously (IV) in broiler chickens.Study designTwo phase study: Phase 1, randomized up-and-down study to determine effective dose 50 (ED50) for lidocaine; Phase 2, prospective randomized study to determine the cardiovascular effects of lidocaine.AnimalsSeventeen Ross-708 broiler chickens (Gallus gallus domesticus) 11 chickens (Phase 1) and 6 chickens (Phase 2)], weighing 2.6–4.3 kg.MethodsAfter induction of anesthesia with isoflurane and placement of monitoring equipment including invasive blood pressure, chickens were administered lidocaine IV. During Phase 1, using an up-and-down design, each animal received a variable dose selected based on the response of the previous animal. During Phase 2, each animal was administered 6 mg kg−1 of lidocaine IV over 2 minutes. Clinically irrelevant cardiovascular effects were defined as a relative decrease of heart rate (HR) and mean blood pressure (MAP) <30% subsequent to IV lidocaine administration. The ED50 was defined as the dose rate that would cause clinically irrelevant cardiovascular depression in 50% of the population.ResultsDuring Phase 1, using an up-and-down study design (n = 11), the ED50 of lidocaine was determined to be 6.30 mg kg−1 and 6.22 mg kg−1 (95% confidence interval, 5.30–7.13 mg kg−1), when calculated by Dixon's up-and-down method, and logistic regression, respectively. During Phase 2, following infusion of lidocaine (6 mg kg−1), no clinically relevant effects on HR or MAP were detected in any animal.Conclusions and clinical relevancePrevious reports state that the dose of lidocaine used in birds should be =4 mg kg−1. In this study, 6 mg kg−1 of lidocaine injected IV was not associated with adverse cardiovascular effects. These results suggest that the dose of 4 mg kg−1 can be exceeded, at least in chickens, and opens the possibility of other therapeutic uses for lidocaine in birds. |
| |
| Keywords: | avian bird lidocaine local anesthesia Ross‐708 toxicity |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
