Turunen Heta, Raekallio Marja R, Honkavaara Juhana M, Restitutti Flavia, Kallio-Kujala Ira J, Adam Magdy, Nevanperä Katri, Scheinin Mika, Männikkö Sofia K, Hautajärvi Heidi J, Larenza Menzies Paula, Vainio Outi M
Am J Vet Res. 2019 Oct;80(10):912-922. doi: 10.2460/ajvr.80.10.912.
To investigate the cardiovascular and sedation reversal effects of IM administration of atipamezole (AA) in dogs treated with medetomidine hydrochloride (MED) or MED and vatinoxan (MK-467).
8 purpose-bred, 2-year-old Beagles.
A randomized, blinded, crossover study was performed in which each dog received 2 IM treatments at a ≥ 2-week interval as follows: injection of MED (20 μg/kg) or MED mixed with 400 μg of vatinoxan/kg (MEDVAT) 30 minutes before AA (100 μg/kg). Sedation score, heart rate, mean arterial and central venous blood pressures, and cardiac output were recorded before and at various time points (up to 90 minutes) after AA. Cardiac and systemic vascular resistance indices were calculated. Venous blood samples were collected at intervals until 210 minutes after AA for drug concentration analysis.
Heart rate following MED administration was lower, compared with findings after MEDVAT administration, prior to and at ≥ 10 minutes after AA. Mean arterial blood pressure was lower with MEDVAT than with MED at 5 minutes after AA, when its nadir was detected. Overall, cardiac index was higher and systemic vascular resistance index lower, indicating better cardiovascular function, in MEDVAT-atipamezole-treated dogs. Plasma dexmedetomidine concentrations were lower and recoveries from sedation were faster and more complete after MEDVAT treatment with AA than after MED treatment with AA.
Atipamezole failed to restore heart rate and cardiac index in medetomidine-sedated dogs, and relapses into sedation were observed. Coadministration of vatinoxan with MED helped to maintain hemodynamic function and hastened the recovery from sedation after AA in dogs.
研究肌内注射阿替美唑（AA）对接受盐酸美托咪定（MED）或MED与伐替考昔（MK - 467）治疗的犬的心血管和镇静逆转作用。
8只2岁的纯种比格犬。
进行了一项随机、双盲、交叉研究，每只犬以≥2周的间隔接受2次肌内注射治疗，如下：在注射AA（100μg/kg）前30分钟注射MED（20μg/kg）或MED与400μg/kg伐替考昔混合液（MEDVAT）。在注射AA前及之后的不同时间点（长达90分钟）记录镇静评分、心率、平均动脉压和中心静脉压以及心输出量。计算心脏和全身血管阻力指数。在注射AA后直至210分钟期间定期采集静脉血样进行药物浓度分析。
在注射AA之前及之后≥10分钟时，与MEDVAT给药后的结果相比，MED给药后的心率较低。在注射AA后5分钟检测到平均动脉压最低点时，MEDVAT组的平均动脉压低于MED组。总体而言，接受MEDVAT - 阿替美唑治疗的犬的心脏指数较高，全身血管阻力指数较低，表明心血管功能更好。与MED治疗后用AA相比，MEDVAT治疗后用AA时，血浆右美托咪定浓度较低，镇静恢复更快且更完全。
阿替美唑未能恢复美托咪定镇静犬的心率和心脏指数，且观察到有再次陷入镇静的情况。MED与伐替考昔联合给药有助于维持犬的血流动力学功能，并加速注射AA后的镇静恢复。
