NASAL PRESSURE SUPPORT VENTILATION PLUS OXYGEN COMPARED WITH OXYGEN-THERAPY ALONE IN HYPERCAPNIC COPD

Non-invasive ventilation has been used in chronic respiratory failure due to chronic obstructive pulmonary disease (COPD), but the effect of the addition of nasal positive-pressure ventilation to long-term oxyg en therapy (LTOT) has not been determined. We report a randomized cros sover study of the effect of the combination of nasal pressure support ventilation (NP5V) and domiciliary LTOT as compared with LTOT alone i n stable hypercapnic COPD. Fourteen patients were studied, with values (mean +/- SD) of Pa-O2 of 45.3 +/- 5.7 mm Hg, Pa-CO2 of 55.8 +/- 3.6 mm Hg, and FEV(1) of 0.86 +/- 0.32 L. A 4 wk run-in period (on usual t herapy) was followed by consecutive 3-mo periods of: (I) oxygen therap y alone, and (2) oxygen plus NPSV in randomized order. Assessments wer e made during run-in and at the end of each study period. There were s ignificant improvements in daytime arterial Pa-O2 and Pa-CO2, total sl eep time, sleep efficiency, and overnight Pa-CO2 following 3 mo of oxy gen plus NPSV as compared with run-in and oxygen alone. Quality of lif e with oxygen plus NPSV was significantly better than with oxygen alon e. The degree of improvement in daytime Pa-CO2 was correlated with the improvement in mean overnight Pa-CO2. Nasal positive-pressure ventila tion may be a useful addition to LTOT in stable hypercapnic COPD.