Krimins Rebecca A, Ko Jeff C, Weil Ann B, Payton Mark E, Constable Peter D
Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Purdue University, West Lafayette, IN 47907, USA.
Am J Vet Res. 2012 Sep;73(9):1363-70. doi: 10.2460/ajvr.73.9.1363.
To evaluate hemodynamic effects in dogs after IM administration of dexmedetomidine (7.5 μg/kg, butorphanol (0.15 mg/kg), and tiletamine-zolazepam (3 mg/kg [DBTZ]) or dexmedetomidine (15 μg/kg), butorphanol (0.3 mg/kg), and ketamine (3 mg/kg [DBK]).
5 healthy adult mixed-breed dogs.
Each dog received DBTZ and DBK in a randomized crossover study with a 48-hour interval between treatments. Anesthesia was induced and maintained with sevoflurane in 100% oxygen while instrumentation with Swan-Ganz and arterial catheters was performed. Following instrumentation, hemodynamic measurements were recorded at 3.54% (1.5 times the minimum alveolar concentration) sevoflurane; then sevoflurane administration was discontinued, and dogs were allowed to recover. Six hours after cessation of sevoflurane administration, baseline hemodynamic measurements were recorded, each dog was given an IM injection of DBTZ or DBK, and hemodynamic measurements were obtained at predetermined intervals for 70 minutes.
DBTZ and DBK induced hypoventilation (Paco2, approx 60 to 70 mm Hg), respiratory acidosis (pH, approx 7.2), hypertension (mean arterial blood pressure, approx 115 to 174 mm Hg), increases in systemic vascular resistance, and reflex bradycardia. Cardiac output, oxygen delivery, and oxygen consumption following DBTZ or DBK administration were similar to those following sevoflurane administration to achieve a surgical plane of anesthesia. Blood l-lactate concentrations remained within the reference range at all times for all protocols.
In healthy dogs, both DBTZ and DBK maintained oxygen delivery and oxygen consumption to tissues and blood lactate concentrations within the reference range. However, ventilation should be carefully monitored and assisted when necessary to prevent hypoventilation.
评估在犬体内肌肉注射右美托咪定（7.5微克/千克）、布托啡诺（0.15毫克/千克）和替来他明-唑拉西泮（3毫克/千克[DBTZ]）或右美托咪定（15微克/千克）、布托啡诺（0.3毫克/千克）和氯胺酮（3毫克/千克[DBK]）后对血流动力学的影响。
5只健康成年杂种犬。
在一项随机交叉研究中，每只犬接受DBTZ和DBK，治疗间隔为48小时。使用七氟醚在100%氧气中诱导并维持麻醉，同时进行Swan-Ganz导管和动脉导管插管。插管后，在七氟醚浓度为3.54%（最低肺泡浓度的1.5倍）时记录血流动力学测量值；然后停止给予七氟醚，让犬恢复。在停止给予七氟醚6小时后，记录基线血流动力学测量值，每只犬肌肉注射DBTZ或DBK，并在预定时间间隔内获取血流动力学测量值，持续70分钟。
DBTZ和DBK诱导通气不足（动脉血二氧化碳分压，约60至70毫米汞柱）、呼吸性酸中毒（pH值，约7.2）、高血压（平均动脉血压，约115至174毫米汞柱）、全身血管阻力增加和反射性心动过缓。给予DBTZ或DBK后的心输出量、氧输送和氧消耗与给予七氟醚以达到手术麻醉平面后的情况相似。在所有方案中，血中l-乳酸浓度始终保持在参考范围内。
在健康犬中，DBTZ和DBK均能维持组织的氧输送和氧消耗，且血乳酸浓度在参考范围内。然而，必要时应仔细监测通气并给予辅助，以防止通气不足。
