Endobronchial cryotherapy in the treatment of tracheal strictures.

Modern advances in ventilatory support systems have introduced a patient population requiring long term endotracheal intubation or tracheostomy. The formation of tracheal strictures in such patients remains a very significant clinical problem despite new modifications in endotracheal tube design and materials. Dissatisfied with standard modalities of treatment for these lesions, we have explored the usefulness of endobronchial cryotherapy for the treatment of such stricture. Cervical tracheal strictures were produced in 11 sheep. In six animals a prototype cryosurgical probe was passed through the bronchoscope and these lesions frozen to -80 degrees C. Respiratory epithelial regeneration was complete, but significant reduction in strictures was not noted. Utilizing the cryosurgical probe in conjunction with the endobronchial resection of tracheal strictures in three animals did, however, produce significant reduction in stricture size. Healing following cryonecrosis was associated with minimal fibrosis. Endobronchial cryotherapy is easily performed and has been well tolerated by these animals.