Study design (if review, criteria of inclusion for studies)
Dual intervention cross-over trial over 2 days
Participants
Only those with previous positive response to salbutamol SK score 35 - 90 9 participants (4 males), age range 6 - 22 years
Interventions
Sequence A: salbutamol 200 mcg, salbutamol 400 mcg and ipratropium 80 mcg by MDI and aerochamber separated by 45 minutes; or Sequence B: ipratropium 80 mcg, salbutamol 200 mcg, salbutamol 400 mcg Randomised to:
Outcome measures
Only 4 hour data used Changes in spirometry (FVC, FEV1, FEF25-75, FEF50, PEFR, FRC, RV, Raw ) measured at baseline, before each drug in the sequence and at 4 hours and 8 hours from baseline
Main results
The FEV1 and Raw improved from baseline after each inhalation, and at 4 and 8 h during both days (p < 0.05). Forty-five minutes after S 200 micrograms, plus S 400 micrograms, FEV1, FRC, and Raw were not significantly different compared with the values 45 min after IB 80 micrograms, plus S 200 micrograms (1.67 +/- 0.1 vs 1.63 +/- 0.1 L; 2.81 +/- 0.6 vs 2.65 +/- 0.5 L; and 2.98 +/- 0.2 vs 2.66 +/- 0.1 cm H2O/L/s, respectively). The PFTs were not significantly different after maximal doses of IB (80 micrograms) compared with S (600 micrograms). The HR and SaO2 were not significantly different from baseline throughout the study period.
Authors' conclusions
These results indicate that both single and sequential therapy have a similar acute bronchodilator effect provided that large doses are used. We speculate that adrenergic and muscarinic pathways are equally important in airflow obstruction in patients with CF.