Noninvasive ventilation in hypercapnic acute respiratory failure due to chronic obstructive pulmonary disease vs. other conditions: effectiveness and predictors of failure.
OBJECTIVE
This study compared the effectiveness of noninvasive ventilation (NIV) and the risk factors for NIV failure in hypercapnic acute respiratory failure (ARF) due to chronic obstructive pulmonary disease (COPD) vs. non-COPD conditions.


METHODS
Prospective cohort study in the medical intensive care unit of a university hospital.


METHODS
111 patients with hypercapnic ARF, 43 of whom had COPD exacerbations and 68 other conditions. Baseline characteristics of the two groups were similar.


RESULTS
The risk of NIV failure, defined as the need for endotracheal intubation, was significantly lower in COPD than in other conditions (19% vs. 47%). High APACHE II score was an independent predictor of NIV failure in COPD (OR 5.38 per 5 points). The presence of pneumonia (OR 5.63), high APACHE II score (OR 2.59 per 5 points), rapid heart rate (OR 1.22 per 5 beats/min), and high PaCO(2) 1 h after NIV (OR 1.22 per 5 mmHg) were independent predictors of NIV failure in the non-COPD group. Failure of NIV independently predicted mortality (OR 10.53).


CONCLUSIONS
Noninvasive ventilation was more effective in preventing endotracheal intubation in hypercapnic ARF due to COPD than non-COPD conditions. High APACHE II score predicted NIV failure in both groups. Noninvasive ventilation was least effective in patients with hypercapnic ARF due to pneumonia.
Phua
Jason
J
Division of Respiratory and Critical Care Medicine, Department of Medicine, National University Hospital, Singapore. mdclimtk@nus.edu.sg
Kong
Kien
K
Lee
Kang Hoe
KH
Shen
Liang
L
Lim
T K
TK
D018806:APACHE; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D005260:Female; D006801:Humans; D006935:Hypercapnia / Q000503:physiopathology*; D007362:Intensive Care Units; D007442:Intubation, Intratracheal; D008297:Male; D008875:Middle Aged; D011175:Positive-Pressure Respiration; D011446:Prospective Studies; D029424:Pulmonary Disease, Chronic Obstructive / Q000150:complications* / Q000503:physiopathology; D012131:Respiratory Insufficiency / Q000209:etiology / Q000628:therapy*; D012846:Singapore; D016896:Treatment Outcome
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