A new technique for oral endotracheal airway access in rabbits under fluoroscopic control:: An easy way for drug administration in chronic experiments

Endotracheal drug administration plays an important role in rabbit models of pulmonary injury and lung disease. However, anatomical features of the oral fissure and pharynx of rabbits make orotracheal intubation a difficult task with a high failure rate. We developed a new technique for airway access in rabbits under fluoroscopic control using a balloon catheter. The procedure consists of four major steps: (1) a shortened 5-french vertebralis catheter is placed into the mesopharynx just above the epiglottic valve, (2) through the catheter lumen a guidewire is carefully moved across the epiglottis and inserted into the trachea, (3) the vertebralis catheter is replaced by a balloon catheter that subsequently is introduced into the tracheal tree over the guidewire, and (4) with the balloon catheter in the right position the guidewire is removed and the balloon is inflated so that finally the drug can be delivered. This procedure was performed in 55 New Zealand White rabbits under general anesthesia with ketamine/xylazine. In all 55 cases the procedure was performed successfully without any major complications and within a reasonably short time period. Removal of the catheter and awakening of the animals were uneventful. The described technique is a simple and safe method for airway access in rabbits and can be useful in chronic experiments for endotracheal drug administration.