Abstract
OBJECTIVE: To investigate and demonstrate persistent increase of peak cough flow after mechanical in-exsufflator application, in patients with neuromuscular diseases and pneumonia. METHODS: A mechanical in-exsufflator was applied with patients in an upright or semi-upright sitting position (pressure setting, +40 and -40 cmH2O; in-exsufflation times, 2-3 and 1-2 seconds, respectively). Patients underwent five cycles, with 20-30 second intervals to prevent hyperventilation. Peak cough flow without and with assistive maneuvers, was evaluated before, and 15 and 45 minutes after mechanical in-exsufflator application. RESULTS: Peak cough flow was 92.6 L/min at baseline, and 100.4 and 100.7 L/min at 15 and 45 minutes after mechanical in-exsufflator application, respectively. Assisted peak cough flow at baseline, 15 minutes, and 45 minutes after mechanical in-exsufflator application was 170.7, 179.3, and 184.1 L/min, respectively. While peak cough flow and assisted peak cough flow increased significantly at 15 minutes after mechanical in-exsufflator application compared with baseline (p=0.030 and p=0.016), no statistical difference was observed between 15 and 45 minutes. CONCLUSION: Increased peak cough flow after mechanical in-exsufflator application persists for at least 45 minutes.