A Protocol for Prolonged Surgical Anaesthesia with Recovery in Fire Salamanders Using Tricaine Mesylate (MS-222): A...

Area of Science:

• Veterinary Anesthesiology
• Amphibian Research
• Wildlife Medicine

Background:

• Anesthesia protocols for amphibians, particularly prolonged procedures, require careful consideration of drug efficacy and physiological impact.
• Tricaine methanesulfonate (MS-222) is a commonly used anesthetic in aquatic species, but its application for extended surgical anesthesia in salamanders needs detailed description.

Purpose of the Study:

• To describe a protocol for prolonged surgical anesthesia and recovery in fire salamanders (Salamandra salamandra) using tricaine methanesulfonate (MS-222).
• To evaluate the efficacy and safety of MS-222 for extended anesthesia durations in this species.
• To monitor key physiological parameters during anesthesia and recovery.

Main Methods:

• Fourteen fire salamanders underwent anesthesia using buffered MS-222 solutions (0.5-4 g/L, pH 7.0) for electromyography wire implantation.
• Anesthesia was maintained via partial immersion and topical application of oxygenated MS-222 solution (0.5-3 g/L).
• Physiological parameters including heart rate (HR) and pulse oximetry (SpO2) were monitored throughout the procedure.

Main Results:

• The mean time to loss of righting reflex was 13.7 ± 2.2 minutes.
• The average duration of anesthesia was 111 ± 24.2 minutes, with a mean recovery time of 31 ± 10.3 minutes.
• Heart rate significantly decreased during anesthesia (p ≤ 0.0001), and SpO2 dropped from a baseline of 85.5% to 61% during surgery, improving to 80.5% upon recovery.

Conclusions:

• Prolonged surgical anesthesia and recovery are achievable in fire salamanders using buffered dilutions of MS-222.
• Reflectance pulse oximetry (SpO2) monitoring can be a valuable tool during MS-222 immersion anesthesia in amphibians.
• Further research into optimizing anesthetic protocols and monitoring techniques for amphibians is warranted.