OUTCOME OF COPD PATIENTS PERFORMING NOCTURNAL NONINVASIVE MECHANICAL VENTILATION

The role of non-invasive nocturnal domiciliary ventilation (NNV) in ch ronic obstructive pulmonary disease (COPD) patients with chronic hyper capnia is still discussed. The aims of this study were to evaluate the longterm survival, clinical effectiveness and side-effects of NNV in these patients. Forty-nine stable hypercapnic COPD patients on long-te rm oxygen therapy (LTOT) were assigned to two groups: in Group 1, 28 p atients performed NNV by pressure support modality in addition to LTOT ; in Group 2, 21 patients continued their usual LTOT regimen. Treatmen t was assigned according to the compliance to NNV, after an in hospita l period. Mortality rate, hospital stay (KS) and ICU admissions (IA) w ere recorded in the two groups. HS and IA were compared to those recor ded in a similar period of follow-back. Lung and respiratory muscle fu nction, dyspnoea, and exercise capacity (by 6-min walk test) were eval uated baseline and every 3-6 months up to 3 yr. Mean follow-up time wa s 35 +/- 7 months. Mortality rate was not different between the two gr oups: 16, 33, 46% and 13, 28, 50% at 1, 2 and 3 yr in Groups 1 and 2 r espectively. Lung and respiratory muscle function did not significantl y change over time. A significant increase in 6-min walk test (from 24 5 +/- 78 to 250 +/- 88, 291 +/- 75, 284 +/- 89 m after 1, 2 and 3 yr r espectively, P<0.01) was observed only in patients undergoing NNV. In comparison to the follow back HS significantly decreased in both group s (from 37 +/- 29 to 15 +/- 12 and from 32 +/- 18 to 17 +/- 11 days/pt /yr in Groups 1 and 2 respectively, P<0.001) whereas IA significantly decreased only in patients performing also NNV (from 1.0 +/- 0.7 to 0. 2 +/- 0.3/pt/yr, P<0.0001). Addition of NNV by pressure support modali ty to LTOT does not improve long term survival but significantly reduc es ICU admissions and improves exercise capacity in severe COPD with h ypercapnia.