Noninvasive ventilation in chronic obstructive pulmonary disease, bronchiectasis and cystic fibrosis.

Although long-term oxygen therapy (LTOT) improves survival, it has little effect on hypoventilation and other outcomes in patients with hypercapnic respiratory failure due to chronic obstructive pulmonary disease (COPD). Recent studies have shown that the use of noninvasive positive-pressure ventilation, when used in combination with LTOT in selected stable COPD patients, controls hypoventilation and improves daytime arterial blood gases, sleep quality, health status and may have a benefit in reducing exacerbation frequency and severity. Patients who show the greatest reduction in overnight carbon dioxide tension in arterial blood with ventilation are most likely to benefit from long-term ventilatory support. Some benefits have also been shown in patients with chronic respiratory failure due to bronchiectasis and cystic fibrosis, though survival is inferior in this patient group. As most studies of noninvasive positive-pressure ventilation in chronic obstructive pulmonary disease have been relatively short term, large multicentre studies with survival, exacerbations and hospital admissions as the primary end points are required to evaluate longer term effects.