Long term effects of non-invasive mechanical ventilation on pulmonary haemodynamics in patients with chronic respiratory failure.
BACKGROUND
It is not known whether long term nocturnal mechanical ventilation (NMV) reduces pulmonary hypertension in patients with chronic respiratory failure (CRF).


METHODS
Pulmonary haemodynamics, spirometric values, and gas exchange were studied in 33 patients requiring NMV due to CRF (20 with thoracic restriction, 13 with chronic obstructive pulmonary disease (COPD)) at baseline and after 1 year of NMV given in the volume cycled mode. Patients with COPD also received supplemental oxygen.


RESULTS
Long term NMV improved gas exchange while lung function remained unchanged. Mean pulmonary artery pressure at rest before NMV was higher in patients with thoracic restriction than in those with COPD (33 (10) mm Hg v 25 (6) mm Hg). After 1 year of NMV mean pulmonary artery pressure decreased in patients with thoracic restriction to 25 (6) mm Hg (mean change -8.5 mm Hg (95% CI -12.6 to -4.3), p<0.01) but did not change significantly in patients with COPD (mean change 2.2 mm Hg (95% CI -0.3 to 4.8)).


CONCLUSIONS
Long term NMV in CRF improves pulmonary haemodynamics in patients with thoracic restriction but not in patients with COPD.
Schönhofer
B
B
Krankenhaus Kloster Grafschaft, Zentrum für Pneumologie, Beatmungs- und Schlafmedizin, D-57392 Schmallenberg-Grafschaft, Germany. Bernd.Schoenhofer@t-online.de
Barchfeld
T
T
Wenzel
M
M
Köhler
D
D
D002908:Chronic Disease; D005260:Female; D005541:Forced Expiratory Volume / Q000502:physiology; D006801:Humans; D006976:Hypertension, Pulmonary / Q000503:physiopathology / Q000628:therapy*; D008173:Lung Diseases, Obstructive / Q000150:complications / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011659:Pulmonary Gas Exchange / Q000502:physiology; D012121:Respiration, Artificial / Q000295:instrumentation / Q000379:methods*; D012131:Respiratory Insufficiency / Q000209:etiology / Q000503:physiopathology / Q000628:therapy*; D018709:Statistics, Nonparametric; D014797:Vital Capacity / Q000502:physiology