新西兰白兔在 alfaxalone-右美托咪定-咪达唑仑麻醉后给予氧气时出现通气不足。

Hypoventilation following oxygen administration associated with alfaxalone-dexmedetomidine-midazolam anesthesia in New Zealand White rabbits.

机构信息

Faculty of Veterinary Medicine, Université de Montréal, Saint-Hyacinthe, QC, Canada; Groupe de recherché en pharmacologie animale du Québec (GREPAQ), Université de Montréal, Saint-Hyacinthe, QC, Canada; Department of Veterinary Clinical and Diagnostic Sciences, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada.

出版信息

Vet Anaesth Analg. 2020 Sep;47(5):637-646. doi: 10.1016/j.vaa.2020.04.012. Epub 2020 May 29.

DOI:10.1016/j.vaa.2020.04.012

PMID:32727673

Abstract

OBJECTIVE

To investigate the relationship between oxygen administration and ventilation in rabbits administered intramuscular alfaxalone-dexmedetomidine-midazolam.

STUDY DESIGN

Prospective, randomized, blinded study.

ANIMALS

A total of 25 New Zealand White rabbits, weighing 3.1-5.9 kg and aged 1 year.

METHODS

Rabbits were anesthetized with intramuscular alfaxalone (4 mg kg), dexmedetomidine (0.1 mg kg) and midazolam (0.2 mg kg) and randomized to wait 5 (n = 8) or 10 (n = 8) minutes between drug injection and oxygen (100%) administration (facemask, 1 L minute). A control group (n = 9) was administered medical air 10 minutes after drug injection. Immediately before (PRE5/10) and 2 minutes after oxygen or medical air (POST5/10), respiratory rate (f), pH, PaCO, PaO, bicarbonate and base excess were recorded by an investigator blinded to treatment allocation. Data [median (range)] were analyzed with Wilcoxon, Mann-Whitney U and Kruskal-Wallis tests and p < 0.05 considered significant.

RESULTS

Hypoxemia (PaO < 88 mmHg, 11.7 kPa) was observed at all PRE times: PRE5 [71 (61-81) mmHg, 9.5 (8.1-10.8) kPa], PRE10 [58 (36-80) mmHg, 7.7 (4.8-10.7) kPa] and PRE10 [48 (32-64) mmHg, 6.4 (4.3-8.5) kPa]. Hypoxemia persisted when breathing air: POST10 [49 (33-66) mmHg, 6.5 (4.4-8.8) kPa]. Oxygen administration corrected hypoxemia but was associated with decreased f (>70%; p = 0.016, both groups) and hypercapnia (p = 0.016, both groups). Two rabbits (one per oxygen treatment group) were apneic (no thoracic movements for 2.0-2.5 minutes) following oxygen administration. f was unchanged when breathing air (p = 0.5). PaCO was higher when breathing oxygen than air (p < 0.001).

CONCLUSIONS AND CLINICAL RELEVANCE

Early oxygen administration resolved anesthesia-induced hypoxemia; however, f decreased and PaCO increased indicating that hypoxemic respiratory drive is an important contributor to ventilation using the studied drug combination.

摘要

目的

研究肌肉注射阿法沙龙-右美托咪定-咪达唑仑后给兔吸氧与通气的关系。

研究设计

前瞻性、随机、盲法研究。

动物

共 25 只新西兰白兔，体重 3.1-5.9 公斤，年龄 1 岁。

方法

兔肌肉注射阿法沙龙（4mg/kg）、右美托咪定（0.1mg/kg）和咪达唑仑（0.2mg/kg）麻醉，随机分为药物注射后 5（n=8）或 10（n=8）分钟给予氧气（面罩，1L/min）。对照组（n=9）在药物注射后 10 分钟给予医用空气。在给氧或医用空气前即刻（PRE5/10）和 2 分钟后（POST5/10），由一位不了解治疗分配的研究者记录呼吸频率（f）、pH 值、PaCO、PaO、碳酸氢盐和碱剩余。数据[中位数（范围）]用 Wilcoxon、Mann-Whitney U 和 Kruskal-Wallis 检验进行分析，p<0.05 为差异有统计学意义。

结果

所有 PRE 时间均观察到低氧血症（PaO<88mmHg，11.7kPa）：PRE5[71（61-81）mmHg，9.5（8.1-10.8）kPa]、PRE10[58（36-80）mmHg，7.7（4.8-10.7）kPa]和 PRE10[48（32-64）mmHg，6.4（4.3-8.5）kPa]。空气呼吸时低氧血症持续存在：POST10[49（33-66）mmHg，6.5（4.4-8.8）kPa]。给氧纠正了低氧血症，但与呼吸频率降低（>70%；p=0.016，两组）和高碳酸血症（p=0.016，两组）有关。给氧后，2 只兔子（每组 1 只）出现呼吸暂停（2.0-2.5 分钟无胸壁运动）。空气呼吸时呼吸频率无变化（p=0.5）。给氧时 PaCO 高于空气（p<0.001）。