Heliox on the Work of Breathing in Adult Patients With Lower Airway Stenosis

Heliox (a mixture of Helium and Oxygen) can reduce the work of breathing in patients with airway stenosis by modifying turbulent flow into laminar flow. The aim of this study was to analyze the effect of Heliox versus conventional oxygen therapy in patients with lower airway stenosis on muscular effort measured by electromyography and diaphragmatic ultrasound, thoracoabdominal synchrony assessed with plethysmographic bands, dyspnea, stridor, oxygen saturation, transcutaneous carbon dioxide value, blood pressure, heart rate and respiratory rate.

Inclusion Criteria: * Patients with lower airway stenosis evaluated at the Respiratory Endoscopy Unit of the Hospital Universitario 12 de Octubre on the waiting list for endoscopic intervention on stenosis. * Stenosis grade ≥ 3 and Borg scale score \> 2. Exclusion Criteria: * Presence of relevant comorbidities (uncontrolled ischemic heart disease, ventricular dysfunction, pneumopathies with severe respiratory insufficiency, severe pulmonary hypertension). * Inability to perform the test due to severe dyspnea or need for emergency intervention. * Patient on continuous mechanical ventilation, invasive or non-invasive.