Section Anaesthesiology, Vetsuisse Faculty, University of Zurich, Zürich, Switzerland.
Section Anaesthesiology, Vetsuisse Faculty, University of Zurich, Zürich, Switzerland.
Vet Anaesth Analg. 2023 Sep;50(5):397-407. doi: 10.1016/j.vaa.2023.05.004. Epub 2023 May 29.
To compare the cardiovascular effects of a combination of medetomidine and vatinoxan (MVX) versus medetomidine (MED) alone administered intramuscularly (IM) and to determine whether heart rate (HR) can be used as a surrogate for cardiac output (CO) after the use of medetomidine with or without vatinoxan.
A randomized, blinded, experimental, crossover study.
A group of eight healthy Beagle dogs aged 4.6 (2.3-9.4) years and weighing 12.9 (9-14.7) kg, median (range).
Each dog was injected with 1 mg m medetomidine with or without 20 mg m vatinoxan IM with a washout period of 7 days. Cardiovascular data and arterial and mixed venous blood gas samples were collected at baseline, 5, 10, 15, 20, 35, 45, 60, 90 and 120 minutes after treatment administration. CO was measured at all time points via thermodilution. Differences between treatments, period and sequence were evaluated with repeated measures analysis of covariance and the relationship between HR and CO was assessed with a repeated measures analysis of variance; p values < 0.05 were deemed significant.
The CO was 47-96% lower after MED than after MVX (p < 0.0001). Increases in systemic, pulmonary arterial and right atrial pressures and oxygen extraction ratio were significantly higher after MED than after MVX (all p < 0.0001). HR was significantly lower after MED and the linear relationship to CO was significant (p < 0.0001).
Overall, MED affected the cardiovascular system more negatively than MVX, and the difference in cardiovascular function between the treatments can be considered clinically relevant. HR was linearly related to CO, and decreases in HR reflected cardiac performance for dogs sedated with medetomidine with or without vatinoxan.
比较肌肉注射（IM）咪达唑仑（MED）联合伐替洛尔（MVX）与 MED 单药对心血管的影响，并确定在使用 MED 或 MED 联合伐替洛尔后，心率（HR）是否可作为心输出量（CO）的替代指标。
随机、双盲、实验、交叉研究。
一组 8 只健康比格犬，年龄 4.6（2.3-9.4）岁，体重 12.9（9-14.7）kg，中位数（范围）。
每组犬均接受 1mg/m MED 联合或不联合 20mg/m MVX IM 注射，洗脱期为 7 天。在治疗前、治疗后 5、10、15、20、35、45、60、90 和 120 分钟时采集心血管数据和动脉及混合静脉血气样本。所有时间点均通过热稀释法测量 CO。采用重复测量协方差分析评估处理、时期和序列之间的差异，采用重复测量方差分析评估 HR 与 CO 之间的关系；p 值＜0.05 被认为具有统计学意义。
与 MVX 相比，MED 后 CO 降低 47%-96%（p＜0.0001）。与 MVX 相比，MED 后全身、肺动脉和右心房压力及氧摄取率升高更为显著（均 p＜0.0001）。与 MVX 相比，MED 后 HR 显著降低，与 CO 呈显著线性关系（p＜0.0001）。
总的来说，MED 对心血管系统的影响比 MVX 更为明显，两种药物的心血管功能差异可被认为具有临床相关性。HR 与 CO 呈线性关系，HR 降低反映了咪达唑仑或咪达唑仑联合伐替洛尔镇静犬的心脏功能。
