The investigators are looking at the effect of humidified nasal high-flow with oxygen (HNHF-O2) on air exchange during exacerbations of COPD. HNHF-O2 therapy may have beneficial effects in patients with severe breathing impairment that results in low oxygen in the blood. Some studies show that patients with low blood oxygen levels who use HFNC oxygen have lower rates of needing mechanical ventilation.

Patients admitted to the hospital with an exacerbation of COPD accompanied by respiratory failure need supplemental oxygen and alleviation of an increased work of breathing. Patients with acute exacerbations of COPD have hypoxemia, hypercapnia and an elevated work of breathing due to increased airways obstruction and hyperinflation. Patient outcomes can be improved by aggressive bronchodilation and systemic corticosteroids, but methods that can augment spontaneous ventilation and decrease the work of breathing can help avoid intubation. High flow nasal cannula (HFNC) has been shown to be useful in patients with severe hypoxemic respiratory failure and those recently extubated from mechanical ventilation. HFNC provides warmed and humidified high flow (10-60L/min) by nasal cannula that allows precise titration of % inspired FiO2 in the air/oxygen blend. The AIRVO 2 device delivers warmed and humidified respiratory gases to spontaneously breathing patients using a humidifier and integrated flow generator. In this study, the air/ oxygen gas blend (20-35L/min) will be administered by the AIRVO 2 HNHF device to achieve an fraction of inspired oxygen (FiO2) > 90% at rest. A potential advantage of the AIRVO 2 HNHF device includes the ability of the device to deliver oxygen that has been warmed and humidified. Also, the high flow rates achieved with this device may reduce the work of breathing. This is an open-labeled pilot study of ten patients to determine the safety and feasibility of using the device in the management of patients with an acute exacerbation of COPD with acute on chronic respiratory failure.

Inclusion Criteria:

• Males and females 40 years of age or older
• Hospitalized for an acute exacerbation of COPD on the 6th floor of Rock Pavilion (pulmonary inpatient service)
• Smoking history of > 10 pack-years
• PaCO2 ≥ 45 mm Hg
• Able to provide informed consent
• Willing to participate in daily measurements of arterial blood gases, completion of study questionnaires, and other study-related procedures

Exclusion Criteria:

• Upper airway or nasal problems that prohibit the use of humidified high-flow nasal oxygen
• Hemodynamic instability defined as the need for blood pressure or blood volume support to maintain adequate tissue perfusion and oxygenation
• Urgent need for endotracheal intubation
• A do-not-intubate order
• A known diagnosis of obstructive sleep apnea
• Present use of continuous positive airway pressure (CPAP) or bilevel positive airway pressure (BIPAP) therapy