Anaesthesia for lambs undergoing spinal surgery: a case series

Six 1-month-old lambs were anaesthetized for cervical spinal cord surgery. Anaesthesia was induced with intravenous midazolam (0.5 mg/kg) then halothane delivered by mask in an O2-N2O mixture. After endotracheal intubation, the lungs were ventilated mechanically and anaesthesia maintained with halothane and nitrous oxide. Buprenorphine and flunixin were given before and after surgery, and the wound margin was infiltrated with 0.5% bupivacaine solution. Neuromuscular block was produced with repeated injections of atracurium; neuromuscular transmission was restored with edrophonium. Lambs made a rapid recovery without obvious signs of discomfort, sedation, or weakness after operations lasting up to 156 min. Anaesthesia was induced in a seventh lamb using etomidate, which probably contributed to death during recovery from anaesthesia.