Anaesthesia for the neonatal pig--'the micropig'.

The use of spontaneous respiration of oxygen, nitrous oxide, and halothane via Jackson Rees's modification of Ayre's T-piece and a flexible 'snout' mask proved to be a simple and effective way of anaesthetizing neonatal pigs--'micropigs'--in the first few days of life without resorting to endotracheal intubation. No airway obstruction occurred as long as the head was extended with firm traction on the jaw and provided the nostrils were not pressed up against the wall of the mask. The anaesthetic technique described provided adequate muscle relaxation and analgesia for extensive abdominal surgery. The animals recovered rapidly and there were no postoperative complications.