PT - JOURNAL ARTICLE AU - Nicolas Terzi AU - Isabelle Vaugier AU - Claude Guérin AU - Hélène Prigent AU - Ghilas Boussaid AU - Karl Leroux AU - Mathieu Delorme AU - Frédéric Lofaso AU - Bruno Louis TI - Comparison of Four Mechanical Insufflation-Exsufflation Devices: Effect of Simulated Airway Collapse on Cough Peak Flow AID - 10.4187/respcare.10086 DP - 2023 Apr 01 TA - Respiratory Care PG - 462--469 VI - 68 IP - 4 4099 - http://rc.rcjournal.com/content/68/4/462.short 4100 - http://rc.rcjournal.com/content/68/4/462.full AB - BACKGROUND: Mechanical insufflation-exsufflation (MI-E) devices are used to improve airway clearance in individuals with acute respiratory failure. Some MI-E devices measure cough peak flow (CPF) during MI-E to optimize pressure adjustments. The aim was to compare CPF and effective cough volume (ECV: volume expired/coughed > 3 L/s) measurements between 4 MI-E devices under simulated conditions of stable versus collapsed airway.METHODS: Four MI-E devices were tested on the bench. Each device was connected via a standard circuit to a collapsible tube placed in an airtight chamber that was attached to a lung model with adjustable compliance and resistance. Pressure was measured upstream and downstream the collapsing tube; air flow was measured between the chamber and the lung model. Each device was tested in 2 conditions: collapse condition (0 cm H2O) and no-collapse condition (−70 cm H2O). For each condition, 6 combinations of inspiratory/expiratory pressures were applied. CPF was measured at the “mouth level” by the device built-in flow meter and at the “tracheal level” by a dedicated pneumotachograph. Comparisons were performed with non-parametric tests.RESULTS: CPF values measured at the tracheal level and ECV values differed between devices for each inspiratory/expiratory pressure in the collapse and no-collapse conditions (P < .001). CPF values were significantly lower at the tracheal level in the collapse as compared with the no-collapse condition (P < .001 for each device), whereas they were higher at the mouth level (P < .05) for 3 of the 4 devices.CONCLUSIONS: CPF values differed significantly across MI-E devices, highlighting limitation(s) of using only CPF values to determine cough effectiveness. In simulated of airway collapse, CPF increased at the mouth, whereas it decreased at the tracheal level.