The anterior cricoid split in puppies.

The acute and long-term effects of the anterior cricoid split on the subglottis of puppies intubated from 7 to 14 days are documented. The anterior cricoid split acutely increased the intralumenal cricoid surface area in puppies with intubation-induced airway injury. An intense inflammatory response with mucosal ulceration and granulation tissue is elicited by 14 days of intubation by using the canine model of induced subglottic stenosis developed by Supance et al. [19]. When animals intubated for 14 days underwent an anterior cricoid split on day 7, the airway appears essentially normal by day 14. The split cricoid cartilage maintained a 'U' configuration following the procedure. The region of deficient cartilage anteriorly is bridged by fibrous tissue with normal epithelium lining the lumenal surface. Splitting the cricoid cartilage anteriorly increased the intralumenal area and no long term complications resulted from the procedure. The mechanisms by which the anterior cricoid split expands the airway intralumenal area while maintaining airway support have been reviewed.