The key role of noninvasive
positive pressure ventilation (NPPV) is well documented in
chronic obstructive pulmonary disease (
COPD) patients with acute
respiratory failure (ARF) since it may avoid endotrachal intubation in >50% of cases when used as the initial treatment. However, currently only minimal 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 clearly a need for prospective studies comparing long-term
oxygen therapy (LTOT) and NPPV in the most severe
COPD in a large amount of patients and on a real long-term basis of several years. Two randomized prospective studies are being completed in Europe and the first preliminary results show that NPPV is associated with a reduction of hospitalization for chronic
respiratory failure decompensation. The main beneficial effect of long-term
mechanical ventilation in
COPD patients with chronic
respiratory failure implies a correction of nocturnal
hypoventilation that could persist beyond the ventilation period because of a temporary improvement in
carbon dioxide sensitivity that is often blunted in these patients. A synthesis from the literature suggest to consider NPPV for severe
COPD patients who present with chronic
hypoxia and
hypercapnia and develop an unstable respiratory condition. Instability may be appreciated on a clinical basis and confirmed by a progressive worsening of arterial blood gas tensions, leading to frequent cardiorespiratory decompensations with ominous ARF episodes. NPPV should also be considered after an ARF episode successfully treated by
noninvasive ventilation but with the impossibility to wean the patient from the
ventilator. Thus, noninvasive
positive pressure ventilation could be proposed as a preventive treatment in severe
chronic obstructive pulmonary disease patients with 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.