Heliox and forward-leaning posture improve the efficacy of nebulized bronchodilator in acute asthma: a randomized trial.

BACKGROUND Heliox and forward-leaning posture (torso inclined forward at 50-60° with the elbows resting on the thighs) are adjuncts in the administration of nebulized bronchodilator to patients with acute asthma. METHODS We randomized 59 patients who presented to the emergency department in severe asthma crisis, into 4 treatment groups: nebulized bronchodilator + oxygen; nebulized bronchodilator + oxygen + forward-leaning posture; nebulized bronchodilator + heliox; and nebulized bronchodilator + heliox + forward-leaning posture. Before and after the bronchodilator treatments the subjects were seated with torso erect, breathing room air. Each subject received 2 doses, 20 min apart, of nebulized fenoterol (2.5 mg) plus ipratropium bromide (0.25 mg) in 3 mL of 0.9% saline, delivered with a semi-closed valved aerosol reservoir. The nebulizer was run with oxygen or 80:20 heliox. The post-treatment pulmonary function tests were performed 15 min after the second nebulization. The group's mean age was 35.1 ± 13.6 y, and there were 20 men and 39 women. RESULTS The oxygen + forward-leaning-posture group had a greater FEV(1) improvement than the oxygen group (59% vs 38%, P = .02). The heliox + forward-leaning-posture group had a greater FEV(1) improvement than the oxygen group (103% vs 38%, P = .001) and the heliox group (103% vs 42%, P = .03). The heliox group had greater reduction in respiratory rate than the oxygen group (P = .03). The heliox + forward-leaning-posture group had significantly greater peak expiratory flow improvement than any of the other groups. CONCLUSIONS Heliox plus forward-leaning posture during bronchodilator nebulization improves bronchodilator efficacy in patients with severe acute asthma. (ClinicalTrials.gov registration NCT00922350).