Noninvasive positive pressure ventilation in COPD

Home mechanical ventilation, as provided by long-term NPPV, is a widely accepted treatment option for many patient groups with chronic hypercapnic respiratory failure, including also those with COPD, even though the rationale for long-term NPPV in COPD patients is still disputed. This is based on clinical observations that conventional NPPV using assisted ventilation and low mean inspiratory pressures of <18 cmH(2)O reportedly failed to effectively improve respiratory function, most importantly gas exchange, while outcomes are also not convincingly improved by the addition of long-term NPPV to long-term oxygen treatment. Recently, however, a promising technique of NPPV has been described, which aims at maximally improving gas exchange by the use of controlled ventilation and considerably higher inspiratory pressures, typically ranging 20-40 cmH(2)O. This is known as high-intensity NPPV. This approach clearly contrasts with the conventional, low-intensity approach. High-intensity NPPV has been shown to improve physiological parameters such as breathing pattern, gas exchange and lung function. In addition, it also provides clinical benefits, with improvements in dyspnoea, walking distance and specific aspects of health-related quality of life. The superiority of high-over low-intensity NPPV has been clearly established by randomised crossover trials. Increasing evidence now exists to support the contention that long-term high-intensity NPPV offers a new therapeutic option in the treatment of hypercapnic COPD. However, the questions of whether high-intensity NPPV is also capable of improving survival and how to best select candidates to undergo long-term high-intensity NPPV remain pressing. This article also provides detailed practical descriptions of how to initiate high-intensity NPPV.