虎皮鹦鹉（Myiopsitta monachus）的异氟烷最小麻醉浓度和咪达唑仑的节省效应。

Health Sciences Centre, Ontario Veterinary College, University of Guelph, Guelph, ON, Canada.

Department of Clinical Studies, Ontario Veterinary College, University of Guelph, Guelph, ON, Canada.

Vet Anaesth Analg. 2020 May;47(3):341-346. doi: 10.1016/j.vaa.2020.01.005. Epub 2020 Feb 4.

OBJECTIVE

To determine the effects of midazolam on the minimum anesthetic concentration (MAC) reduction of end-tidal isoflurane concentration (Fe'Iso) measured using an electrical stimulus in Quaker parrots (Myiopsitta monachus).

STUDY DESIGN

Randomized crossover experimental study.

ANIMALS

A group of six adult Quaker parrots, weighing 98-124 g.

METHODS

Birds were anesthetized with isoflurane in oxygen delivered by mask, then tracheally intubated and mechanically ventilated. Three treatments were applied with a 4 day interval between anesthetic events. Each anesthetized bird was administered midazolam (1 mg kg; treatment MID1), midazolam (2 mg kg; treatment MID2) or electrolyte solution (control) intramuscularly. The treatments were administered using a replicated Latin square design and the observers were blinded. Based on a pilot bird, the starting Fe'Iso was 1.8%. After equilibration for 10 minutes, a supramaximal stimulus was delivered using an electrical current (20 V and 50 Hz for 10 ms) and birds were observed for non-reflex movement. The Fe'Iso was titrated by 0.1% until a crossover event was observed. The MAC was estimated using logistic regression.

RESULTS

The MAC of isoflurane (MAC) was estimated at 2.52% [95% confidence interval (CI), 2.19-2.85] with a range of 1.85-2.65%. MAC in MID1 was 2.04% (95% CI, 1.71-2.37) and in MID2 was 1.81% (95% CI, 1.48-2.14); reductions in MAC from control of 19% (p = 0.001) and 28% (p < 0.001), respectively. Heart rate, temperature, sex and anesthetic time were not different among treatments.

CONCLUSIONS

Midazolam (1-2 mg kg) intramuscularly resulted in a significant isoflurane-sparing effect in response to a noxious stimulus in Quaker parrots without observable adverse effects.

CLINICAL RELEVANCE

Midazolam can be used as part of a balanced anesthetic approach using isoflurane in Quaker parrots, and potentially in other psittacine species.

目的

确定咪达唑仑对用电刺激测量的 Quaker 鹦鹉（Myiopsitta monachus）呼气末异氟醚浓度（Fe'Iso）最小麻醉浓度（MAC）降低的影响。

研究设计

随机交叉实验研究。

动物

一组六只成年 Quaker 鹦鹉，体重 98-124 克。

方法

鸟类通过面罩吸入异氟醚麻醉，然后气管插管并机械通气。在麻醉事件之间间隔 4 天应用三种处理方法。每只麻醉的鸟类肌内注射咪达唑仑（1mg/kg；治疗 MID1）、咪达唑仑（2mg/kg；治疗 MID2）或电解质溶液（对照）。处理方法采用复制的拉丁方设计，观察者被蒙蔽。根据一只试验鸟，起始 Fe'Iso 为 1.8%。平衡 10 分钟后，使用电流（20V 和 50Hz 持续 10ms）给予最大刺激，并观察鸟类是否有非反射运动。通过 0.1%的异氟醚滴定，直到观察到交叉事件。使用逻辑回归估计 MAC。

结果

异氟醚的 MAC（MAC）估计为 2.52%（95%置信区间（CI），2.19-2.85%），范围为 1.85-2.65%。MID1 的 MAC 为 2.04%（95%CI，1.71-2.37%），MID2 的 MAC 为 1.81%（95%CI，1.48-2.14%）；对照的 MAC 降低了 19%（p=0.001）和 28%（p<0.001）。心率、体温、性别和麻醉时间在处理之间没有差异。