Smith J M, Stump K C
Program of Comparative Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, USA.
Contemp Top Lab Anim Sci. 2000 Nov;39(6):39-42.
Isoflurane is one of the safest and most accepted anesthetic agents for reptiles, birds, and mammals. It has also been used in terrestrial amphibians. The use of inhalation agents in an entirely aquatic frog presents a new dilemma for delivery in contrast to terrestrial species. The African Clawed Frog respires by using both transcutaneous gas exchange and air breathing. These frogs remain submerged for long periods of time, thus making standard inhalation techniques impractical. We tested five methods for delivering isoflurane: 1) bubbling isoflurane and oxygen in the water, 2) intracoelomic injection, 3) subcutaneous injection, 4) intramuscular injection, and 5) topical application. For the topical application, we developed a simple technique by using an absorptive pad with a vapor-barrier backing, saturating the pad with the liquid isoflurane, and placing the pad on the back of the frog while it was confined in a plastic bowl. Although two of the three injectable routes induced anesthesia, only the topical route produced rapid induction with consistent, safe recovery. Bubbling isoflurane with oxygen into water was unsuccessful. Topical application of isoflurane was most successful and appears to be a safe and practical method that can be used as an alternative to tricaine methylsulphonate, hypothermia, or other methods for anesthetizing African Clawed Frogs.
异氟烷是用于爬行动物、鸟类和哺乳动物的最安全且最被认可的麻醉剂之一。它也已被用于陆生两栖动物。与陆生物种相比，在完全水生的青蛙中使用吸入性麻醉剂带来了新的给药难题。非洲爪蟾通过经皮气体交换和空气呼吸两种方式进行呼吸。这些青蛙会长时间保持水下状态，因此标准的吸入技术并不实用。我们测试了五种给予异氟烷的方法：1）在水中鼓入异氟烷和氧气；2）体腔注射；3）皮下注射；4）肌肉注射；5）局部应用。对于局部应用，我们开发了一种简单技术，即使用带有蒸汽屏障背衬的吸收垫，用液体异氟烷将垫子浸湿，然后将垫子放在被限制在塑料碗中的青蛙背部。虽然三种注射途径中的两种可诱导麻醉，但只有局部应用途径能快速诱导麻醉并实现持续、安全的苏醒。将异氟烷与氧气鼓入水中未成功。异氟烷的局部应用最为成功，似乎是一种安全实用的方法，可作为三卡因甲磺酸盐、低温麻醉或其他麻醉非洲爪蟾方法的替代方法。
