Anaesthesia for lambs undergoing spinal surgery: a case series

Area of Science:

• Veterinary Anesthesiology
• Surgical Procedures in Animals
• Animal Models for Neurological Research

Background:

• Cervical spinal cord surgery in young animals requires careful anesthetic management.
• Assessing anesthetic safety and efficacy in lambs is crucial for preclinical research.
• Minimizing pain and discomfort post-surgery is a primary concern in animal welfare.

Purpose of the Study:

• To describe and evaluate an anesthesia protocol for cervical spinal cord surgery in 1-month-old lambs.
• To assess the recovery and welfare of lambs undergoing prolonged surgical procedures.
• To identify potential risks associated with specific anesthetic agents in this model.

Main Methods:

• Six lambs underwent anesthesia using midazolam, halothane, and nitrous oxide for cervical spinal cord surgery.
• Mechanical ventilation, analgesia (buprenorphine, flunixin), and local anesthesia (bupivacaine) were employed.
• Neuromuscular blockade with atracurium was reversed using edrophonium.

Main Results:

• Lambs experienced rapid recovery without apparent discomfort, sedation, or weakness after surgeries up to 156 minutes.
• One lamb anesthetized with etomidate experienced an adverse event, likely contributing to its death during recovery.
• The primary anesthetic regimen (midazolam, halothane, N2O) appeared safe and effective for this surgical model.

Conclusions:

• Anesthesia with midazolam, halothane, and nitrous oxide supports successful cervical spinal cord surgery and recovery in young lambs.
• Etomidate may pose a significant risk for lambs during the recovery phase from anesthesia.
• This anesthetic approach facilitates the use of lambs as a model for spinal cord research.