Anesthesia of six-week-old New Zealand White rabbits for thoracotomy

Many methods of administering surgical anesthesia to rabbits have been described. We are studying the effects of anterior thoracic spinal procedures on the growth of young rabbit spines. We introduce a method for intubation using direct laryngoscopy without the need for specially manufactured or costly equipment and for administration of anesthesia applicable to six-week-old New Zealand White (NZW) rabbits. Induction of anesthesia was initiated with 5% isoflurane in a sealed plastic anesthesia box. No premedication was given. We performed direct laryngoscopy by using an otoscope. Under direct visualization, a 5-French polypropylene catheter was passed through the speculum of the otoscope and advanced through the vocal cords. The endotracheal tube without the adapter then was advanced over this guide. A vigorous cough reflex was noted as the tube passed through the vocal cords. We have found this cough reflex to be a very reliable indicator of correct placement. Throughout the surgical procedure, anesthesia was maintained with isoflurane delivered from a standard small-animal anesthetic machine using pediatric breathing hoses, y-piece, and ventilator. Recovery after surgery was rapid.