Shrinking the room for invasive mechanical ventilation in acute chronic hypercapnic respiratory failure: yes, but must be sure to have opened windows for noninvasive ventilation

Abstract

Dear Editor In the last decade, the treatment and prognosis of chronic obstructive pulmonary disease (COPD) patients have been improved by noninvasive ventilation (NIV).1 However, the choice between invasive mechanical ventilation (IMV) and NIV, is still influenced by several critical factors.2 We read with interest the original article and related commentary by Scarpazza et al, reporting a very high NIV success rate in patients with acute hypercapnic respiratory failure due to acute exacerbations of COPD (AECOPD) with related reduction in IMV-associated complications.3 Nevertheless, although NIV represents one of the most important progresses in pulmonary medicine in the last decade, we believe that there are still some unresolved questions. First, there are interhospital differences in the organization of NIV provisions.4 Second, the final decision on indications and modalities of NIV in patients with AECOPD should rely on experience and guidelines.5 Third, there is a subgroup of patients not yet clearly evaluated, such as elderly with comorbidities, where studies are limited and do not provide a clear message. Furthermore the influence of COPD stage and underlying cause of AECOPD in outcome of mechanical ventilation is difficult to estimate.6 Fourth, devices and settings differ among countries, sometimes with scarce perspectives of improvement due to economic aspects.7 We believe that there is clear scientific evidence of effect of NIV in these patients. The room for IMV is small, but it must still have open windows to any situation in deciding the type of mechanical ventilation.