Noninvasive ventilation and obstructive lung diseases

The key role of noninvasive positive pressure ventilation (NPPV) is well do cumented in chronic obstructive pulmonary disease (COPD) patients with acut e respiratory failure (ARF) since it may avoid endotrachal intubation in > 50%, of cases when used as the initial treatment, However, currently only m inimal data is available to assess usefulness of NPPV in COPD patients on a long-term basis. Even if such studies are difficult to manage, there is cl early a need for prospective studies comparing longterm oxygen therapy (LTO T) and NPPV in the most severe COPD in a large amount of patients and on a real long-term basis of several gears. Two randomized prospective studies a re being completed in Europe and the first preliminary results show that NP PV is associated with a reduction of hospitalization for chronic respirator y failure decompensation. The main beneficial Effect of long-term mechanical ventilation in CORD pati ents with chronic respiratory failure implies a correction of nocturnal hyp oventilation that could persist beyond the ventilation period because of a temporary improvement in carbon dioxide sensitivity that is often blunted i n these patients. A synthesis from the literature suggest to consider NPPV for severe CORD pa tients who present with chronic hypoxia and hypercapnia and develop an unst able respiratory condition. Instability mag. be appreciated on a clinical b asis and confirmed by a progressive worsening of arterial blood gas tension s, leading to frequent cardiorespiratory decompensations with ominous ARF e pisodes. NPPV should also be considered after an ARF episode successfully t reated by noninvasive ventilation but with the impossibility to wean the pa tient from the ventilator. Thus, noninvasive positive pressure ventilation could be proposed as a prev entive treatment in severe chronic obstructive pulmonary disease patients w ith unstable respiratory condition associated with fluctuating hypercapnia before, during and after an acute respiratory failure episode, avoiding the need for a tracheotomy, Adjunction of noninvasive ventilation to exercise rehabilitation is under evaluation.