Efficacy of long-term noninvasive positive pressure ventilation in stable hypercapnic COPD patients with respiratory failure: a meta-analysis of randomized controlled trials

Abstract

IntroductionThe efficacy of long-term noninvasive positive pressure ventilation (NPPV) in stable hypercapnic COPD patients with respiratory failure remains unclear. The aim of this meta-analysis was to critically assess the efficacy of long-term NPPV on mortality, acute exacerbation, exercise capacity, symptoms and significant physiological parameters (lung function, respiratory muscle function and gas exchange).Patients and methodsWe performed an electronic literature search using the PubMed, Cochrane Library, Embase, OVID and Chinese Biomedical Literature Database in May 2017. Studies comparing treatment effects of NPPV with oxygen therapy in stable hypercapnic COPD patients with respiratory failure were conducted, and at least one of the following parameters were reviewed: frequency of acute exacerbation, mortality, lung function, respiratory muscle function, gas exchange, exercise capacity.ResultsSeven studies with 810 subjects were identified. The partial pressure of arterial carbon dioxide (PaCO2) significantly decreased in patients who received long-term NPPV (weighted mean difference [WMD] −3.73, 95% CI: −5.83 to −1.64, P=0.0005). No significant difference was found in mortality, partial pressure of arterial oxygen (PaO2), frequency of acute exacerbation, lung function, respiratory muscle function and exercise capacity. The subgroup analysis showed that NPPV significantly improved the survival of patients when it was targeted at greatly reducing hypercapnia (WMD 0.35, 95% CI: 0.19 to 0.64, P=0.0006).ConclusionThe results indicate that long-term NPPV decreases the PaCO2 of stable hypercapnic COPD patients with respiratory failure and improves mortality with the aim of reducing PaCO2.

GOLD Reports on Chronic Obstructive Pulmonary Disease (COPD): Evolutions, Revolutions and Controversies

“…Finally, while the first studies of long-term non-invasive ventilation in COPD patients were disappointing, two more recent trials found a survival benefit in markedly hypercapnic patients who had been admitted for respiratory failure. What these studies had in common was the relatively high-pressure settings and ambitious targets in terms of partial pressure carbon dioxide (PaCO 2 ) reduction 69 .…”

Pulmonary rehabilitation, physical activity, respiratory failure and palliative respiratory care

“…In patients with obesity hypoventilation syndrome, recent data suggest that NIV and CPAP results in a similar improvement in arterial blood gas measurement and health-related quality of life 62. A meta-analysis assessing the efficacy of long-term NIV in patients with COPD has shown that the arterial PaO 2 of carbon dioxide (PaCO 2 ) can be decreased with NIV with mortality improved with a significant reduction in PaCO 2 by NIV 63. This is supported by recent studies that have demonstrated that effective NIV, with the aim of significantly reducing elevated PaCO 2 , is well tolerated and associated with improvements in quality of life64 and long-term survival 65.…”

Is positive airway pressure therapy underutilized in chronic obstructive pulmonary disease patients?

“…Although all-cause mortality alone was not reduced in this study (adjHR 0.67 95%CI 0.34; 1.30; P=0.23), home-based NIPPV significantly prolonged time to readmission or death from 1.4 months to 4.3 months (table 1). A more recent meta-analysis of NIPPV and bilevel PAP therapy in stable patients with COPD in 2017 by Liao and colleagues reported no significant difference in mortality [33]. However, in a subgroup analysis involving studies that demonstrated a significant reduction in hypercapnia, there was a reduction in mortality [33].…”

“…A more recent meta-analysis of NIPPV and bilevel PAP therapy in stable patients with COPD in 2017 by Liao and colleagues reported no significant difference in mortality [33]. However, in a subgroup analysis involving studies that demonstrated a significant reduction in hypercapnia, there was a reduction in mortality [33]. Moreover, studies with higher levels of pressure assist were more likely to yield favorable effects and these were more likely to be studies performed in Europe (table 1).…”

“…Therefore, although similar number of deaths (factored into a pooled odds ratio) may be observed, there is still need and interest in a therapeutic intervention that can decrease the rate at which the death occurs. Therefore, unlike prior meta-analysis in this area [30,33] statistical approaches that take into consideration the time-to-event outcomes using hazard ratios (HRs) and thereby including both the number and the timing of events are needed of all the studies enumerated in Table 1 [34,35].…”