Departments of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, Ontario N1G 2W1, Canada,
Toronto Zoo, Toronto, Ontario M1B 5K7, Canada.
J Zoo Wildl Med. 2019 Sep;50(3):579-588. doi: 10.1638/2019-0024.
The study objective was to evaluate the sedative, muscle relaxant, and cardiorespiratory effects of midazolam and flumazenil in the ball python (). Ten healthy adult female ball pythons were used in a randomized and blinded crossover trial evaluating the effects of two dosages (1 and 2 mg/kg intramuscular [i.m.] in the cranial third of the body). In a subsequent open trial, nine ball pythons received 1 mg/kg i.m. of midazolam followed by 0.08 mg/kg i.m. of flumazenil 60 min later. Heart rate, respiratory rate, temperature, and the level of sedation and muscle relaxation (using a semiobjective scoring system) were evaluated. There were no significant differences between midazolam dosages for any of the parameters evaluated. Sedation scores were significantly increased compared with baseline from 15 min (1 mg/kg) and 10 min (2 mg/kg) postinjection up until 56 hr (1 mg/kg) and 72 hr (2 mg/kg) postinjection. Peak effect was reached 60 min postinjection, with 60% of snakes (6/10) being unable to right themselves. One snake developed paradoxical excitation with the 2 mg/kg dosage. Heart rates were significantly lower than baseline from 30 min to 128 hr postinjection with both midazolam dosages. Respiratory rates were significantly lower than baseline at four time points, with the highest dosage only: 15, 45, 60 min, and 8 hr postinjection. Flumazenil resulted in reversal of sedation and muscle relaxation in all snakes within 10 min of administration. However, resedation was evident in all snakes 3 hr after reversal. Midazolam administered at 1 and 2 mg/kg i.m. provides a moderate to profound, although prolonged, sedation and muscle relaxation in ball pythons. Flumazenil reverses the effects of midazolam in ball pythons, but its duration of action at the evaluated dosage is much shorter than midazolam, leading to resedation.
本研究旨在评估咪达唑仑和氟马西尼在球蟒中的镇静、肌肉松弛和心肺作用。十只健康成年雌性球蟒参与了一项随机、双盲交叉试验，评估了两种剂量（肌肉注射，身体头部的三分之一处，1 毫克/千克和 2 毫克/千克）的作用。在随后的开放试验中，九只球蟒接受了 1 毫克/千克的咪达唑仑肌肉注射，60 分钟后再接受 0.08 毫克/千克的氟马西尼肌肉注射。评估了心率、呼吸频率、体温以及镇静和肌肉松弛程度（使用半客观评分系统）。在评估的任何参数方面，两种剂量的咪达唑仑之间均无显著差异。与基线相比，注射后 15 分钟（1 毫克/千克）和 10 分钟（2 毫克/千克）时，镇静评分显著升高，直至注射后 56 小时（1 毫克/千克）和 72 小时（2 毫克/千克）。注射后 60 分钟达到峰值效应，60%的蛇（6/10）无法自行翻转。1 条蛇在接受 2 毫克/千克剂量时出现了矛盾性兴奋。两种剂量的咪达唑仑都会导致心率显著低于基线，从注射后 30 分钟到 128 小时。呼吸频率在四个时间点显著低于基线，只有最高剂量：注射后 15、45、60 分钟和 8 小时。氟马西尼在给药后 10 分钟内使所有蛇的镇静和肌肉松弛恢复正常。然而，在逆转后 3 小时，所有蛇都出现了再镇静现象。咪达唑仑肌肉注射 1 毫克/千克和 2 毫克/千克可使球蟒产生中度至深度、尽管时间较长的镇静和肌肉松弛作用。氟马西尼可逆转球蟒中咪达唑仑的作用，但在评估剂量下，其作用持续时间明显短于咪达唑仑，导致再镇静。
