• Respiratory care · Jul 2014

    Comparative Study

    Intrapulmonary Percussive Ventilation superimposed to conventional mechanical ventilation: comparison between volume controlled and pressure controlled mode. A bench study.

    • Guillaume Riffard, Julien Buzenet, and Claude Guérin.
    • Service de Réanimation Polyvalente, Hôpital Nord, Centre Hospitalier Universitaire de Saint-Etienne, Saint-Etienne, France.
    • Respir Care. 2014 Jul 1;59(7):1116-22.

    BackgroundPrevious bench studies suggest that dynamic hyperinflation may occur if intrapulmonary percussive ventilation (IPV) is superimposed on mechanical ventilation in volume controlled continuous mandatory ventilation (VC-CMV) mode. We tested the hypothesis that pressure controlled continuous mandatory ventilation (PC-CMV) can protect against this risk.MethodsAn ICU ventilator was connected to an IPV device cone adapter that was attached to a lung model (compliance 30 mL/cm H2O, resistance 20 cm H2O/L/s). We measured inspired tidal volume (VTI) and lung pressure (Plung). Measurements were first taken with IPV off and the ICU ventilator set to VC-CMV or PC-CMV mode with a targeted VTI of 500 mL. For each mode, an inspiratory time (TI) of 0.8 or 1.5 s and PEEP 7 or 15 cm H2O were selected. The experiments were repeated with the IPV set to either 20 or 30 psi. The dependent variables were differences in VTI (ΔVTI) and Plung with IPV off or on. The effect of VC-CMV or PC-CMV mode was tested with the ICU ventilators for TI, PEEP, and IPV working pressure using repeated measures of analysis of variance.ResultsAt TI 0.8 s and 20 psi, ΔVTI was significantly higher in VC-CMV than in PC-CMV. PEEP had no effect on ΔVTI. At TI 1.5 s and 20 psi and at both TI values at each psi, mode and PEEP had a significant effect on ΔVTI. With the ICU ventilators at TI 1.5 s, PEEP 7 cm H2O, and 30 psi, ΔVTI (mean ± SD) ranged from -27 ± 25 to -176 ± 6 mL in PC-CMV and from 258 ± 369 to 369 ± 16 mL in VC-CMV. The corresponding ranges were -15 ± 17 to -62 ± 68 mL in PC-CMV and 26 ± 21 to 102 ± 95 mL in VC-CMV at TI 0.8 s, PEEP 7 cm H2O, and 20 psi. Similar findings pertained to Plung.ConclusionsWhen IPV is added to mechanical ventilation, the risk of hyperinflation is greater with VC-CMV than with PC-CMV. We recommend using PC-CMV to deliver IPV and adjusting the trigger variable to avoid autotriggering.Copyright © 2014 by Daedalus Enterprises.

      Pubmed     Free full text   Copy Citation     Plaintext  

      Add institutional full text...

    Notes

     
    Knowledge, pearl, summary or comment to share?
    300 characters remaining
    help        
    You can also include formatting, links, images and footnotes in your notes
    • Simple formatting can be added to notes, such as *italics*, _underline_ or **bold**.
    • Superscript can be denoted by <sup>text</sup> and subscript <sub>text</sub>.
    • Numbered or bulleted lists can be created using either numbered lines 1. 2. 3., hyphens - or asterisks *.
    • Links can be included with: [my link to pubmed](http://pubmed.com)
    • Images can be included with: ![alt text](https://bestmedicaljournal.com/study_graph.jpg "Image Title Text")
    • For footnotes use [^1](This is a footnote.) inline.
    • Or use an inline reference [^1] to refer to a longer footnote elseweher in the document [^1]: This is a long footnote..

    hide…