Thermal ablation (use of treatment modalities that generate heat) has become a widely used tool for treatment of central airway obstruction (e.g. laser, electrocautery, radiofrequency, and argon plasma coagulation). However, this method carries with it an increased risk for airway fire - a surgical fire that occurs in a patient's airway and could also include a fire in the attached breathing circuit. To decrease the risk of airway fire during mechanical ventilation with an endotracheal tube, the concentration of inspired oxygen (FiO2) is set below 40% while waiting for end tidal oxygen concentration (EtO2) to fall below 40% prior to starting thermal ablation. There is no published literature describing O2 concentration within the airways (AiO2) during jet ventilation with rigid bronchoscopy. The co-investigators of this study have recently collected data on AiO2 during rigid bronchoscopy using manual low frequency jet ventilation/high frequency jet ventilation with a period of apnea. The intent of this study is to measure the time taken for the central airway oxygen concentration to drop from 90 to 40% when the "laser mode" is activated on the Monsoon jet ventilator. Ventilation is continued during "laser mode."

Inclusion Criteria:

• Patients undergoing rigid bronchoscopy for treatment of central airway obstruction at FV UMMC will be identified.
• 18 years or older
• Need rigid bronchoscopy as pre-determined by the interventional pulmonologist

Exclusion Criteria:

• Refusal to sign consent
• Pregnant patients
• Hemodynamic instability defined as continuous infusion of medication in order to support blood pressure and/or heart rate/rhythm
• Respiratory instability defined as SpO2<90% with >90% supplemental oxygen.
• Ineligible for rigid bronchoscopic intubation
• Latex allergy
• Evidence of fistulous airway
• Active Bronchopleural fistula

Patients undergoing rigid bronchoscopy for treatment of central airway obstruction at FV UMMC will be identified.