Cryospray Therapy Versus Standard of Care for Benign Airway Stenosis (CryoStasis)

Benign central airway stenosis (BCAS) is an important cause of both pulmonary morbidity and mortality. Notable causes include post-intubation stenosis, collagen vascular diseases, airway trauma, infectious and idiopathic subglottic stenosis (iSGS). Surgery is the preferred definite option; however, the first therapeutic attempt is usually endoscopic to temporarily restore airway patency and symptomatic improvement. Several endoscopic modalities exist for treatment. Most commonly, thermal or laser therapy to make radial incisions into the stenotic lesion, followed by balloon dilation to increase the area of patency. Clinicians may also inject steroids or antineoplastic agents such as mitomycin C. All of these methods have benefits and associated risks. Symptomatic stenosis frequently reoccurs with these methods. For example, the investigators have been doing 3-4 ballon dilations procedures a week at our institution. Spray cryotherapy (SCT) is a novel FDA-cleared technique that allows for liquid nitrogen to be delivered through the working channel of a bronchoscope. Few retrospective studies exist without more robust clinical trial data to reduce the risk of bias and support its widespread use. The investigators postulate that SCT and standard of care techniques will improve airway patency volume at six months than the standard of care techniques alone. Some of the proposed advantages include improved wound healing which may translate to less scar tissue and thus improvements in airway patency for a longer duration of time.