Effects of Long-term Dry and Humidified Low-flow Oxygen Via Nasal Cannula

During normal breathing, the upper and lower airways performs the priming of inspired gas: humidification, heating and filtering from nose to the bronchios for adequate gas exchange occurs in the lungs. Many patients with severe or advanced cardiopulmonary conditions (cystic fibrosis, chronic obstructive pulmonary disease, pulmonary hypertension, advanced heart failure among others) may develop chronic respiratory failure and require treatment with oxygen therapy. High fractions of inspired oxygen have been associated with deleterious effects on the nasal ciliary beating and nose mucociliary transport. At home assistance, the patient with chronic respiratory receives oxygen via nasal cannula to the patient has been applied with and without humidification, however, does not know the effects of these two types of dry and humidified administration on the mucosa of the nose, airways and lungs. The investigators will assess the subject in use of home oxygen therapy at baseline, 12 hours, 7 days 30 days, 12 months and 24 months.