Noninvasive ventilation using a mouthpiece in patients with chronic obstructive pulmonary disease and acute respiratory failure.

BACKGROUND

Noninvasive positive pressure ventilation (NPPV) delivered via a mouthpiece (mNPPV) has been successfully used in stable chronic restrictive respiratory insufficiency, but not in patients with chronic obstructive pulmonary disease (COPD) and acute respiratory failure (ARF).

OBJECTIVES

The purpose of this matched case-control study was to compare the usefulness of mNPPV to noninvasive ventilation using a nasal or oronasal mask (nNPPV) or standard medical treatment (SMT) in COPD patients with ARF.

METHODS

Twenty-nine patients receiving mNPPV were matched with 29 patients receiving nNPPV and 29 patients receiving SMT regarding age, SAPSII, admission PaCO(2) and pH.

RESULTS

In the mNPPV group, admission PaCO(2) and pH were 78.6 +/- 12 mm Hg and 7.30 +/- 0.04, respectively. mNPPV and nNPPV avoided the need for endotracheal intubation in 27 and 25 patients, respectively (nonsignificant) whereas SMT resulted in a higher mechanical ventilation rate (13 patients). At the end of the treatment protocol, PaCO(2) was lower in the mNPPV group (62.2 +/- 9.6 mm Hg) than in the SMT group (72.4 +/- 20.4 mm Hg, p < 0.018) leading to a significantly higher pH. No significant differences were observed between the mNPPV and nNPPV groups.

CONCLUSIONS

In case of moderate respiratory acidosis, noninvasive ventilation using a mouthpiece significantly reduces the endotracheal intubation rate in comparison with SMT and therefore appears to be a second-line alternative to noninvasive ventilation delivered via a mask, especially when poorly tolerated.