Department of Small Animal Medicine and Surgery, University of Georgia College of Veterinary Medicine, Athens, GA, USA.
Department of Large Animal Medicine, University of Georgia College of Veterinary Medicine, Athens, GA, USA.
Equine Vet J. 2022 Jan;54(1):153-158. doi: 10.1111/evj.13424. Epub 2021 Mar 10.
Matrix fentanyl patches have not been investigated in horses and may represent an effective means of providing analgesia over an extended time period without venous catheterisation.
To describe the pharmacokinetics of a matrix transdermal fentanyl patch in horses.
Randomised experiment, Latin-square design.
Six adult horses were given each of three treatments with a 96-hour washout. For each treatment, two 100 µg/h matrix fentanyl patches were applied to the inguinal region (TXA), metacarpus (TXM) or ventral tail base (TXT) for 72 hours. Blood samples for fentanyl analysis were obtained and heart rate (HR), respiratory rate (RR) and rectal temperature (RT) were measured at various time points for 96 hours. Fentanyl plasma concentrations were measured with LC-MS/MS for pharmacokinetic analysis. A mixed-effects model was used to analyse pharmacodynamic variables.
The time to maximum plasma concentration, maximum plasma concentration and area under the curve extrapolated to infinity were 10 ± 3.79, 14.3 ± 5.13 and 10.3 ± 4.8 hours; 2.07 ± 0.74, 1.55 ± 0.53 and 2.07 ± 0.72 ng/mL; and 46.6 ± 9.3, 44.6 ± 6.0 and 46.2 ± 7.68 ng hours/mL for TXA, TXM and TXT respectively. There was no significant difference among groups. There was no significant change from baseline or among treatment groups with regard to HR, RR or RT (P > .1 for all).
There was no intravenous treatment group for determination of bioavailability.
Fentanyl was rapidly absorbed and persisted in the plasma for up to 96 hours. No adverse effects of treatment on HR, RR or RT were observed. Further controlled prospective studies are needed to determine what plasma concentration, if any, of fentanyl achieves an analgesic effect in horses when administered via a transdermal patch system.
基质芬太尼贴片尚未在马中进行研究，可能代表着一种在无需静脉置管的情况下提供长时间镇痛的有效手段。
描述马中环苯扎明透皮芬太尼贴片的药代动力学。
随机实验，拉丁方设计。
6 匹成年马分别接受 3 种治疗，洗脱期为 96 小时。 每种治疗中，将 2 片 100μg/h 的基质芬太尼贴片分别贴在腹股沟（TXA）、掌骨（TXM）或尾基部腹侧（TXT），持续 72 小时。 在 96 小时内的各个时间点采集芬太尼血样，并测量心率（HR）、呼吸频率（RR）和直肠温度（RT）。 使用 LC-MS/MS 测定芬太尼的血浆浓度，进行药代动力学分析。 采用混合效应模型分析药效学变量。
达峰时间、峰浓度和外推至无穷大的曲线下面积分别为 10±3.79 小时、2.07±0.74 纳克/毫升和 46.6±9.3 纳克/小时/毫升；14.3±5.13 小时、1.55±0.53 纳克/毫升和 44.6±6.0 纳克/小时/毫升；10.3±4.8 小时、2.07±0.72 纳克/毫升和 46.2±7.68 纳克/小时/毫升，用于 TXA、TXM 和 TXT 分别。 组间无显著差异。 与基线或治疗组相比，HR、RR 或 RT 均无显著变化（P>.1 均）。
无静脉治疗组用于确定生物利用度。
芬太尼迅速吸收并在血浆中持续 96 小时。 未观察到治疗对 HR、RR 或 RT 有不良影响。 需要进一步进行对照前瞻性研究，以确定当通过透皮贴系统给药时，芬太尼的何种血浆浓度（如果有的话）可在马中产生镇痛效果。
