Harcourt, ER and John, J and Dargaville, PA and Zannin, E and Davis, PG and Tingay, DG, Pressure and flow waveform characteristics of eight high-frequency oscillators, Pediatric Critical Care Medicine, 15, (5) pp. e234-240. ISSN 1529-7535 (2014) [Refereed Article]
© 2014 The Society of Critical Care Medicine and the World Federation of Pediatric Intensive and Critical Care Societies
DESIGN: In vitro benchtop study.
SETTING: Tertiary pediatric teaching hospital.
INTERVENTIONS: Eight oscillators were evaluated using a test lung; mean airway pressure 10 and 20 cm H2O; frequencies 5, 10, and 15 Hz; pressure amplitude 30 cm H2O (or equivalent); compliance 1.0 mL/cm H2O; and endotracheal tube 3.5 mm. Ventilators tested were Sensormedics 3100A and B (Carefusion), SLE5000 (SLE), Fabian (Acutronic), Leonie+ (Heinen+Löwenstein), Sophie (Stephan), and VN500 and Babylog 8000 (Dräger).
MEASUREMENTS AND MAIN RESULTS: Pressure (airway opening, at oscillator and within the test lung) and airway opening flow waveforms were recorded. Airway opening waveforms were characterized by type (square or sine) and by determining power spectral density analysis. The Sensormedics A and B and the SLE5000 delivered square waves; all other oscillators generated sine waves. Sensormedics, the SLE5000, and the Sophie had a characteristic inspiratory slope (incisura). The pressure waveform within the test lung was a sine wave for all oscillators. Oscillators with square waves or an inspiratory incisura exhibited the highest number of nonfundamental frequency components on power spectral density analysis, suggesting more complex harmonic waveforms with potentially greater transmissive power to the lungs. At frequencies of 5 and 10 Hz, all ventilators, except Babylog 8000, generated airway pressure amplitudes greater than 28.6 cm H2O and tidal volumes greater than 6 mL at the airway opening.
CONCLUSIONS: Current high-frequency oscillators deliver different waveforms. As these may result in variable clinical performance, operators should be aware that these differences exist.
|Item Type:||Refereed Article|
|Keywords:||high-frequency oscillatory ventilation, infant, mechanical ventilation, power spectral density, respiratory monitoring|
|Research Division:||Medical and Health Sciences|
|Research Group:||Paediatrics and Reproductive Medicine|
|Objective Group:||Specific Population Health (excl. Indigenous Health)|
|Objective Field:||Child Health|
|UTAS Author:||Dargaville, PA (Professor Peter Dargaville)|
|Web of Science® Times Cited:||6|
|Deposited By:||Menzies Institute for Medical Research|
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