Selection of commonly used drugs for animal anesthesia

       Animal anesthesia drugs primarily include three types: inhalation anesthetics, injectable anesthetics, and combination anesthetics. The specific choice should be comprehensively determined based on the animal species, surgical requirements, and safety considerations.

       Classification and Characteristics of Major Anesthetic Drugs:

       Inhalation Anesthetics:

       Isoflurane: Suitable for experimental animals such as mice and rats. It offers rapid induction of anesthesia and is primarily metabolized and excreted through the lungs, with minimal impact on liver function.
       Ether: Commonly used for short-term surgeries in rodents. It has a wide safety margin but is flammable and explosive. It should be used with atropine to reduce respiratory secretions.
       Halothane: Suitable for veterinary clinical use. It has strong anesthetic efficacy but requires caution to avoid overdose, which may cause liver and kidney damage.

       Injectable Anesthetics:
       Pentobarbital Sodium: An intermediate-acting barbiturate suitable for small and medium-sized animals such as dogs and cats. Its effects last 2–4 hours, but overdose can easily cause respiratory depression.
       Ketamine: A dissociative anesthetic often used for chemical immobilization of wildlife. It should be combined with xylazine to prolong its effects. Ruminants require atropine pretreatment before use.
       Chloral Hydrate: Suitable for large animals such as horses and dogs. It provides significant sedative effects but has a narrow safety margin and may easily cause mucosal irritation.

       Combination Anesthetics:
       Sumianxin (846 Combination): Contains components such as xylazine and haloperidol. It is commonly used in veterinary practice in China and offers both analgesic and muscle relaxant effects.
       Zoletil 50 Combined with Xylazine: Used for experimental animals such as rats and rabbits. Dosage must be precisely controlled to avoid cardiorespiratory depression.

       Applicable Animals and Special Situations:

       Livestock and Pets:
       Dogs and cats often use ketamine combined with sedatives. Ruminants require preoperative fasting and atropine pretreatment.
       Horses and cattle are recommended to use chloral hydrate or barbiturates. Pigs and sheep can use combination anesthetics such as Baodingning.

       Experimental Animals:
       Mice commonly use isoflurane or tribromoethanol. Rats often employ a combination of Zoletil and xylazine for anesthesia.

       Emergency Anesthesia:
       Barbiturates (such as midazolam) or fentanyl derivatives are primarily used. Professional operation is required to prevent overdose.

       Usage Precautions:

       Dosage Control:
       Strictly calculate based on body weight. For example, the dosage of pentobarbital sodium for dogs is 30–35 mg/kg, and the intramuscular injection dosage of ketamine for dogs is 10–20 mg/kg.

       Risk Assessment:
       Barbiturates are prohibited in animals with cardiorespiratory insufficiency. Ketamine is not suitable for donkeys, mules, or poultry.

       Postoperative Management:
       Monitor body temperature and respiration after anesthesia. When using long-acting drugs such as urethane, pay attention to keeping the animal warm.