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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

Valores medidos de positive end-expiratory pressure (PEEP, pressãoexpiratória final positiva; painel à esquerda) e fluxo expiratório fornecidopelo ventilador (painel à direita) para compensar o vazamento de ar em PEEPde 5 cmH2O (PEEP5) e 10 cmH2O (PEEP10), na forma de média ± dp. Como se podeobservar, os ventiladores Horus e e500 não compensaram adequadamente osvazamentos, fornecendo menos de 0,6 L/s de fluxo compensatório, e não foramcapazes de manter o nível estabelecido de PEEP. *Medida não realizada emvirtude de autodisparo.
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f06: Valores medidos de positive end-expiratory pressure (PEEP, pressãoexpiratória final positiva; painel à esquerda) e fluxo expiratório fornecidopelo ventilador (painel à direita) para compensar o vazamento de ar em PEEPde 5 cmH2O (PEEP5) e 10 cmH2O (PEEP10), na forma de média ± dp. Como se podeobservar, os ventiladores Horus e e500 não compensaram adequadamente osvazamentos, fornecendo menos de 0,6 L/s de fluxo compensatório, e não foramcapazes de manter o nível estabelecido de PEEP. *Medida não realizada emvirtude de autodisparo.

Mentions: No tocante à PEEP e ao vazamento expiratório, o Servo-i, o Vela e o BiPAP Visioncompensaram os vazamentos da MFT durante a expiração, mantendo os valores de PEEPpróximos dos valores estabelecidos (Figura 2).A média dos fluxos emitidos por esses ventiladores a fim de compensar os vazamentosdurante a expiração foi de 0,65 ± 0,12 L/s para PEEP5 e de 0,89 ± 0,16 L/s paraPEEP10. O e500 e o Horus compensaram mal o vazamento e, portanto, não foram capazesde manter a PEEP desejada (Figura 2). Os fluxosmáximos de compensação de vazamento para o e500 e o Horus foram, respectivamente,0,52 ± 0,01 L/s (PEEP5 com a opção de compensação de vazamento ligada) e 0,41 ± 0,01L/s (PEEP10).


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)

Valores medidos de positive end-expiratory pressure (PEEP, pressãoexpiratória final positiva; painel à esquerda) e fluxo expiratório fornecidopelo ventilador (painel à direita) para compensar o vazamento de ar em PEEPde 5 cmH2O (PEEP5) e 10 cmH2O (PEEP10), na forma de média ± dp. Como se podeobservar, os ventiladores Horus e e500 não compensaram adequadamente osvazamentos, fornecendo menos de 0,6 L/s de fluxo compensatório, e não foramcapazes de manter o nível estabelecido de PEEP. *Medida não realizada emvirtude de autodisparo.
© Copyright Policy - open-access
Related In: Results  -  Collection

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

f06: Valores medidos de positive end-expiratory pressure (PEEP, pressãoexpiratória final positiva; painel à esquerda) e fluxo expiratório fornecidopelo ventilador (painel à direita) para compensar o vazamento de ar em PEEPde 5 cmH2O (PEEP5) e 10 cmH2O (PEEP10), na forma de média ± dp. Como se podeobservar, os ventiladores Horus e e500 não compensaram adequadamente osvazamentos, fornecendo menos de 0,6 L/s de fluxo compensatório, e não foramcapazes de manter o nível estabelecido de PEEP. *Medida não realizada emvirtude de autodisparo.
Mentions: No tocante à PEEP e ao vazamento expiratório, o Servo-i, o Vela e o BiPAP Visioncompensaram os vazamentos da MFT durante a expiração, mantendo os valores de PEEPpróximos dos valores estabelecidos (Figura 2).A média dos fluxos emitidos por esses ventiladores a fim de compensar os vazamentosdurante a expiração foi de 0,65 ± 0,12 L/s para PEEP5 e de 0,89 ± 0,16 L/s paraPEEP10. O e500 e o Horus compensaram mal o vazamento e, portanto, não foram capazesde manter a PEEP desejada (Figura 2). Os fluxosmáximos de compensação de vazamento para o e500 e o Horus foram, respectivamente,0,52 ± 0,01 L/s (PEEP5 com a opção de compensação de vazamento ligada) e 0,41 ± 0,01L/s (PEEP10).

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