Exacerbation's Prevention in Patients With COPD in GOLD IV Stage (Very Severe) With Non Invasive Mechanical Ventilation

Background:

• There are many previous studies (no controlled trials or observational studies)that demonstrated minimal benefits (on gas exchange and marginal effect over exacerbations frequency) with the use of non invasive mechanical ventilation, in BiPAP modality with IPAP pressures <18H2ocm (low intensity), in COPD patients.
• In subsequent years there were controled trials that concluded that there was no benefits with the use of non invasive mechanical ventilation on BiPAP mode in COPD patients ( It should be mentioned that in most trials were used low inspiratory pressure levels, that is called low-intensity non invasive mechanical ventilation).
• However, there are other recent studies that described some benefits of high intensity Bilevel modality of non invasive mechanical ventilation (inspiratory pressures >18cmH2O) specially on gas exchange, quality of life and functional status.
• There are some issues that do not yet have a clear answer like the optimal inspiratory pressure (IPAP) or the ventilation modality (BIPAP or other) to obtain the maximal benefit on COPD patients. Additionally, is not clear also if the use of non invasive mechanical ventilation on COPD patients helps to reduce the frequency and severity of acute exacerbations of COPD (AECOPD).

This study have some characteristics that are different to the previous reports:

• The inclusion of patients with frequent exacerbations phenotype (and therefore worst prognosis patients)that there are no included in previous trials
• The intervention maneuver that is bilevel modality of non invasive mechanical ventilation at hig-intensity pressure (>18H2Ocm and <24H2Ocm)
• The use of placebo maneuver (CPAP "Sham")
• The home titration in three phases, over a week
• The long-term use of the intervention and sham maneuver