Combining nitrous oxide with carbon dioxide decreases the time to loss of consciousness during euthanasia in mice--refinement of animal welfare?
Combining nitrous oxide with carbon dioxide decreases the time to loss of consciousness during euthanasia in mice--refinement of animal welfare?
复制标题
DOI：
10.1371/journal.pone.0032290
复制
发表时间：
2012
期刊：
影响因子：
3.7
通讯作者：
Golledge HD
中科院分区：
文献类型：
--
作者：
Thomas AA;Flecknell PA;Golledge HD
二氧化碳（CO2）是啮齿动物最常用的安乐死药物，尽管可能会引起疼痛和痛苦。一氧化二氮用于人体，通过一种称为“第二气体”效应的机制，加速挥发性麻醉剂的麻醉诱导。因此，我们评估了向不断上升的CO2浓度中添加一氧化二氮（N2 O）可通过缩短有意识暴露于CO2的持续时间来用作小鼠安乐死过程的福利改进。首先，为了评估N_2O对小鼠麻醉诱导的影响，12只雌性C57 B1/6小鼠以下列组合交叉麻醉：异氟醚（5%）+O_2（95%）;异氟烷（5%）+N2 O（75%）+O2（25%）和N2 O（75%）+O2（25%），总流速为3 l/min（进入7 l诱导室）。在异氟烷中加入N2 O可使翻正反射消失的时间缩短17.6%。其次，通过逐渐向诱导室中填充CO2（20%室体积.min-1）、CO2+ N2 O（分别为20%和60%室体积. min-1）或CO2+氮气（N2）（20%和60%室体积. min-1），对18只C57 B1/6和18只CD 1小鼠单独实施安乐死。测量动脉O2和CO2分压（Pa）以及血液pH和乳酸。与逐渐升高CO2的安乐死相比，向CO2中加入高浓度N2 O使翻正反射丧失的时间缩短了10.3%（P<0.001），导致PaO 2降低（12.55±3.67 mmHg，P<0.001），乳酸血症升高（4.64±1.04 mmol.l-1，P = 0.026），没有任何表明痛苦的行为。 一氧化二氮减少了在安乐死期间有意识地暴露于逐渐升高的CO2的时间，因此可能减少小鼠在安乐死期间暴露于任何压力或痛苦的持续时间。
Carbon dioxide (CO2) is the most commonly used euthanasia agent for rodents despite potentially causing pain and distress. Nitrous oxide is used in man to speed induction of anaesthesia with volatile anaesthetics, via a mechanism referred to as the “second gas” effect. We therefore evaluated the addition of Nitrous Oxide (N2O) to a rising CO2 concentration could be used as a welfare refinement of the euthanasia process in mice, by shortening the duration of conscious exposure to CO2. Firstly, to assess the effect of N2O on the induction of anaesthesia in mice, 12 female C57Bl/6 mice were anaesthetized in a crossover protocol with the following combinations: Isoflurane (5%)+O2 (95%); Isoflurane (5%)+N2O (75%)+O2 (25%) and N2O (75%)+O2 (25%) with a total flow rate of 3l/min (into a 7l induction chamber). The addition of N2O to isoflurane reduced the time to loss of the righting reflex by 17.6%. Secondly, 18 C57Bl/6 and 18 CD1 mice were individually euthanized by gradually filling the induction chamber with either: CO2 (20% of the chamber volume.min−1); CO2+N2O (20 and 60% of the chamber volume.min−1 respectively); or CO2+Nitrogen (N2) (20 and 60% of the chamber volume.min−1). Arterial partial pressure (Pa) of O2 and CO2 were measured as well as blood pH and lactate. When compared to the gradually rising CO2 euthanasia, addition of a high concentration of N2O to CO2 lowered the time to loss of righting reflex by 10.3% (P<0.001), lead to a lower PaO2 (12.55±3.67 mmHg, P<0.001), a higher lactataemia (4.64±1.04 mmol.l−1, P = 0.026), without any behaviour indicative of distress. Nitrous oxide reduces the time of conscious exposure to gradually rising CO2 during euthanasia and hence may reduce the duration of any stress or distress to which mice are exposed during euthanasia.
登录
查看更多内容
影响因子：
2.4
作者：
FENWICK, DC;BLACKSHAW, JK
通讯作者：
BLACKSHAW, JK
影响因子：
2.4
作者：
Kohler, I;Meier, R;Schatzmann, U
通讯作者：
Schatzmann, U
影响因子：
5.5
作者：
CUNNINGHAM, DJC;HOWSON, MG;PETERSEN, ES
通讯作者：
PETERSEN, ES
影响因子：
7.4
作者：
ANTON, F;EUCHNER, I;HANDWERKER, HO
通讯作者：
HANDWERKER, HO
影响因子：
4.7
作者：
Antognini, JF
通讯作者：
Antognini, JF