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[Therapeutic effect of long-term noninvasive positive pressure ventilation on stable chronic obstructive pulmonary disease: a systematic review].

OBJECTIVE
To determine the efficacy of long-term noninvasive positive pressure ventilation (NPPV) on stable chronic obstructive pulmonary disease (COPD).  


METHODS
Information was collected from the database of China National Knowledge Infrastructure (CNKI), WanFang, WeiPu, PubMed, EMbase, CBM (from the begining to October 2014). Statistical analysis was performed with the Cochrane Collaboration's software RevMan 5.2. 


RESULTS
A total of 23 trials involving 1 200 patients were included. RESULTS showed that NPPV can reduce PaCO2 and improve PaO2 in patients with stable COPD; two years of NPPV can delay the decline in forced expiratory volume in one second (FEV1) and forced vital capacity (FVC), increase six-minutes walk distance (6MWD) and reduce mortality in patients with stable COPD (OR=0.62, 95% CI 0.47 to 0.82). 


CONCLUSION
NPPV can improve the arterial blood gas in patients, and the longer the application of NPPV, the better effect; NPPV can increase exercise endurance and improve the quality of life for the patients; long application of NPPV can delay the decline in FEV1and FVC (2 years or longer); NPPV can reduce the mortality of COPD patients.