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Performance of ICU ventilators during noninvasive ventilation with large leaks in a total face mask: a bench study.

Nakamura MA, Costa EL, Carvalho CR, Tucci MR - J Bras Pneumol (2014 May-Jun)

Bottom Line: The variables analyzed were ventilation trigger, cycling off, total leak, and pressurization.Of the eight ICU ventilators tested, four did not work (autotriggering or inappropriate turning off due to misdetection of disconnection); three worked with some problems (low PEEP or high cycling delay); and one worked properly.The majority of the ICU ventilators tested were not suitable for NIV with a leaky TFM.

View Article: PubMed Central - PubMed

Affiliation: Heart Institute, Hospital das Clínicas, School of Medicine, University of São Paulo, São Paulo, Brazil.

ABSTRACT

Objective: Discomfort and noncompliance with noninvasive ventilation (NIV) interfaces are obstacles to NIV success. Total face masks (TFMs) are considered to be a very comfortable NIV interface. However, due to their large internal volume and consequent increased CO2 rebreathing, their orifices allow proximal leaks to enhance CO2 elimination. The ventilators used in the ICU might not adequately compensate for such leakage. In this study, we attempted to determine whether ICU ventilators in NIV mode are suitable for use with a leaky TFM.

Methods: This was a bench study carried out in a university research laboratory. Eight ICU ventilators equipped with NIV mode and one NIV ventilator were connected to a TFM with major leaks. All were tested at two positive end-expiratory pressure (PEEP) levels and three pressure support levels. The variables analyzed were ventilation trigger, cycling off, total leak, and pressurization.

Results: Of the eight ICU ventilators tested, four did not work (autotriggering or inappropriate turning off due to misdetection of disconnection); three worked with some problems (low PEEP or high cycling delay); and one worked properly.

Conclusions: The majority of the ICU ventilators tested were not suitable for NIV with a leaky TFM.

Show MeSH

Related in: MedlinePlus

Pressurization characteristics of five of the ventilators tested,demonstrated by inspiratory pressure-time product at 500 ms (PTP500; opencircles) and at 1 s (PTPt; filled circles), expressed in percentage of idealarea. The horizontal dashes indicate the means of all measures (positiveend-expiratory pressures of 5 and 10 cmH2O vs. pressure support of5, 10 and 15 cmH2O) available for the ventilators.
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f03: Pressurization characteristics of five of the ventilators tested,demonstrated by inspiratory pressure-time product at 500 ms (PTP500; opencircles) and at 1 s (PTPt; filled circles), expressed in percentage of idealarea. The horizontal dashes indicate the means of all measures (positiveend-expiratory pressures of 5 and 10 cmH2O vs. pressure support of5, 10 and 15 cmH2O) available for the ventilators.

Mentions: The Horus ventilator had the lowest PIP at the mask (Figure E2, available online athttp://www.jornaldepneumologia.com.br/imagebank/images/jbp_v40n3_suplemment.pdf).All of the other ventilators reached similar PIPs. The BiPAP Vision presented with thehighest PTP500 and PTPt values (Figure 3). Thee500 and Horus had the lowest values for PTP500.


Performance of ICU ventilators during noninvasive ventilation with large leaks in a total face mask: a bench study.

Nakamura MA, Costa EL, Carvalho CR, Tucci MR - J Bras Pneumol (2014 May-Jun)

Pressurization characteristics of five of the ventilators tested,demonstrated by inspiratory pressure-time product at 500 ms (PTP500; opencircles) and at 1 s (PTPt; filled circles), expressed in percentage of idealarea. The horizontal dashes indicate the means of all measures (positiveend-expiratory pressures of 5 and 10 cmH2O vs. pressure support of5, 10 and 15 cmH2O) available for the ventilators.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4109202&req=5

f03: Pressurization characteristics of five of the ventilators tested,demonstrated by inspiratory pressure-time product at 500 ms (PTP500; opencircles) and at 1 s (PTPt; filled circles), expressed in percentage of idealarea. The horizontal dashes indicate the means of all measures (positiveend-expiratory pressures of 5 and 10 cmH2O vs. pressure support of5, 10 and 15 cmH2O) available for the ventilators.
Mentions: The Horus ventilator had the lowest PIP at the mask (Figure E2, available online athttp://www.jornaldepneumologia.com.br/imagebank/images/jbp_v40n3_suplemment.pdf).All of the other ventilators reached similar PIPs. The BiPAP Vision presented with thehighest PTP500 and PTPt values (Figure 3). Thee500 and Horus had the lowest values for PTP500.

Bottom Line: The variables analyzed were ventilation trigger, cycling off, total leak, and pressurization.Of the eight ICU ventilators tested, four did not work (autotriggering or inappropriate turning off due to misdetection of disconnection); three worked with some problems (low PEEP or high cycling delay); and one worked properly.The majority of the ICU ventilators tested were not suitable for NIV with a leaky TFM.

View Article: PubMed Central - PubMed

Affiliation: Heart Institute, Hospital das Clínicas, School of Medicine, University of São Paulo, São Paulo, Brazil.

ABSTRACT

Objective: Discomfort and noncompliance with noninvasive ventilation (NIV) interfaces are obstacles to NIV success. Total face masks (TFMs) are considered to be a very comfortable NIV interface. However, due to their large internal volume and consequent increased CO2 rebreathing, their orifices allow proximal leaks to enhance CO2 elimination. The ventilators used in the ICU might not adequately compensate for such leakage. In this study, we attempted to determine whether ICU ventilators in NIV mode are suitable for use with a leaky TFM.

Methods: This was a bench study carried out in a university research laboratory. Eight ICU ventilators equipped with NIV mode and one NIV ventilator were connected to a TFM with major leaks. All were tested at two positive end-expiratory pressure (PEEP) levels and three pressure support levels. The variables analyzed were ventilation trigger, cycling off, total leak, and pressurization.

Results: Of the eight ICU ventilators tested, four did not work (autotriggering or inappropriate turning off due to misdetection of disconnection); three worked with some problems (low PEEP or high cycling delay); and one worked properly.

Conclusions: The majority of the ICU ventilators tested were not suitable for NIV with a leaky TFM.

Show MeSH
Related in: MedlinePlus