PURPOSE: Many airway-obstructed patients with low tidal volumes use handheld percussive devices as part of their treatment regimens. When breathed through, the Acapella (Blue; DHD Healthcare), the Flutter (Axcan Scandipharm), and the Quake (Thayer Medical), generate pressure pulses in the airways of the patient to loosen mucus. In this study, we compared the strength of the pressure pulses (as measured by mean pressure-wave amplitude) generated by these three devices during the exhalation phase of simulated low-volume tidal breathing.
METHODS: Three of each device (n=3) were each evaluated at three different settings (counterclockwise, midpoint, and clockwise dial settings for the Acapella; 0° (horizontal), 20° and 40° alignments for the Flutter; handle turning of 30, 60 and 120 RPM for the Quake). The devices were attached via tubing to a Harvard Apparatus ventilator simulating tidal breathing of 500 mL and 750 mL at 1:1 I:E. Resulting pressure waves were collected with Honeywell ASDX pressure sensors, and analysed in Excel. Device performances were compared via two-tailed T-tests; p ≤; 0.05 indicated a significant difference.
RESULTS: At both the 500 mL and 750 mL tidal volumes, the settings yielding the largest mean pressure-wave amplitudes were midpoint for the Acapella, 0° alignment for the Flutter, and 30 RPM handle turning for the Quake. At 500 mL, the Quake's best setting yielded a mean pressure wave amplitude (9.1 ± 1.4 (SD)cm H2O) that was significantly larger than the best settings of both the Flutter (6.8 ± 0.2 cm H2O), and the Acapella (5.0 ± 0.3 cm H2O). At 750 mL, the Quake's best mean amplitude (14.5 ± 1.6 cm H2O) was also significantly larger than those of the Flutter (9.0 ± 0.1 cm H2O), and the Acapella (6.4 ± 0.5 cm H2O).
CONCLUSION: Under the conditions evaluated, the Quake generated significantly stronger pressure pulses than both the Acapella and Flutter.
CLINICAL IMPLICATIONS: The Quake's stronger pressure pulses should translate into more vigorous airway percussion, and therefore more effective secretion loosening for patients with low tidal volumes.
DISCLOSURE: Paul McGowen, No Product/Research Disclosure Information; Shareholder Co-author Paul McGowen is a shareholder in Thayer Medical Corporation, the manufacturer of one of the devices tested in this study (The Quake); Employee Co-author Paul McGowen is an employee of Thayer Medical Corporation, the manufacturer of one of the devices tested in this study (The Quake); Consultant fee, speaker bureau, advisory committee, etc. Co-author Carl Okeson is a research consultant for Thayer Medical Corporation, the manufacturer of one of the devices tested in this study (The Quake).