From the Authors

From the authors:

We would like to thank T. Koehnlein and T. Welte for their comments on our paper dealing with the use of noninvasive positive pressure ventilation (NPPV) in chronic obstructive pulmonary disease (COPD) patients as recently published in the European Respiratory Journal 1.

They essentially stated that the results of that multicentre study were negative, by observing that the lack of response in most of the physiological and clinical variables could be ascribed to the “relatively” low level of assistance delivered, as a mean, by the ventilator.

However, we keep on thinking about a possible positive role for NPPV in a clearly selected sample of severe COPD patients. Indeed, the long-term protective effect on blood gases (namely, arterial carbon dioxide tension (P_a,CO2)) while breathing oxygen (which is the most common daily condition for those patients) observed in the NPPV group has indirectly shown the actual physiological value of this study 1. Although the pathophysiological reason for this behaviour (different from that observed in the control patients) cannot be drawn from this clinical study, it is reasonable to hypothesise that a probable long-term protection against hypoventilation, as demonstrated previously 2, also still occurred at a lower level of assistance.

Nevertheless, we completely agree with T. Koehnlein and T. Welte in that increasing pressure levels might decrease compliance and affect the physiological response (mainly related to the increasing leaks) of the ventilatory treatment.

Finally, we feel confident that the positive result of the Maugeri Foundation Respiratory Failure item set (MRF-28) questionnaire 3 assessment in the treated subjects, also showed a positive impact of one of the most important end-points of the long-term ventilatory strategy in these patients, which is the health-related quality of life (HRQoL). Although, it is still not clear whether survival can be positively influenced by NPPV in addition to standard long-term oxygen therapy (LTOT), the result obtained on specific HRQoL (together with the positive, although not significant, trend towards the reduction in the follow-up admissions in the critical care area) seems to justify the prescripton of NPPV, at least when a poor condition of the patient (i.e. severe disability, frequent exacerbations and hospitalisations, low effect and clinical control by LTOT) can be proven.

Obviously, any conclusion should be made with caution at present. However, although the prescription of noninvasive positive pressure ventilation cannot be recommended as a generalised option in the chronic obstructive pulmonary disease patients, an effort should be made to look for the best candidates on the basis of their history and the pathophysiological background available.