Transnasal Humidified Rapid-Insufflation Ventilatory Exchange (THRIVE) and Diagnostic Bronchoscopy

Inclusion Criteria: * Patients presenting for diagnostic bronchoscopy Exclusion Criteria: * Patients with significantly decreased myocardial function (ejection fraction \< 50%) * Patients with abnormal cardiac rhythm and conduction abnormalities, except for patients with isolated, asymptomatic premature atrial and ventricular contractions. * Patients with significant peripheral vascular disease, such as those with the symptoms of intermittent claudication. * Patients with known significant cerebrovascular disease, such as history of cerebrovascular accidents (CVAs) and transient ischemic attacks (TIAs). * Patients with significant renal insufficiency, as manifested by estimated glomerular filtration rate (eGFR) \< 60 ml/min/1.73 m2. * Patients with electrolyte (K+, Ca++) abnormalities, as determined by the lab values outside of a normal range. * Patients with the history or symptoms of increased intracranial pressure or reduced intracranial compliance (e.g. headaches, nausea and vomiting, visual changes, mental changes). * Patients with skull base defects. * Patients with pulmonary hypertension who have pulmonary artery pressures above the normal range. * Patients with significant chronic obstructive or restrictive lung diseases, as manifested by known history of baseline chronic hypoxia and/or hypercapnia, and/or baseline room air SpO2 \< 95%. * Obese patients with BMI above 35 kg/m2. * Patients with severe and poorly controlled gastroesophageal reflux disease despite medical treatment. * Patients with hiatal hernia and full stomach patients. * Patients on immunosuppressive medications. * Patient's refusal to participate in the study. * Patients who do not understand English or mentally handicapped. * Pregnant or breastfeeding patients.