Limits...
Bench-test comparison of 26 emergency and transport ventilators.

L'Her E, Roy A, Marjanovic N - Crit Care (2014)

Bottom Line: Leak compensation in most ICU-like and 4/10 sophisticated devices was able to correct at least partially for system leaks, but with variations among ventilators.Major differences were observed between devices and categories, either in terms of general characteristics or technical reliability, across the spectrum of operation.Huge variability of tidal volume delivery with some devices in response to modifications in respiratory mechanics and FIO2 should make clinicians question their use in the clinical setting.

View Article: PubMed Central - PubMed

ABSTRACT

Introduction: Numerous emergency and transport ventilators are commercialized and new generations arise constantly. The aim of this study was to evaluate a large panel of ventilators to allow clinicians to choose a device, taking into account their specificities of use.

Methods: This experimental bench-test took into account general characteristics and technical performances. Performances were assessed under different levels of FIO2 (100%, 50% or Air-Mix), respiratory mechanics (compliance 30,70,120 mL/cmH2O; resistance 5,10,20 cmH2O/mL/s), and levels of leaks (3.5 to 12.5 L/min), using a test lung.

Results: In total 26 emergency and transport ventilators were analyzed and classified into four categories (ICU-like, n = 5; Sophisticated, n = 10; Simple, n = 9; Mass-casualty and military, n = 2). Oxygen consumption (7.1 to 15.8 L/min at FIO2 100%) and the Air-Mix mode (FIO2 45 to 86%) differed from one device to the other. Triggering performance was heterogeneous, but several sophisticated ventilators depicted triggering capabilities as efficient as ICU-like ventilators. Pressurization was not adequate for all devices. At baseline, all the ventilators were able to synchronize, but with variations among respiratory conditions. Leak compensation in most ICU-like and 4/10 sophisticated devices was able to correct at least partially for system leaks, but with variations among ventilators.

Conclusion: Major differences were observed between devices and categories, either in terms of general characteristics or technical reliability, across the spectrum of operation. Huge variability of tidal volume delivery with some devices in response to modifications in respiratory mechanics and FIO2 should make clinicians question their use in the clinical setting.

Show MeSH
Tidal volume accuracy according to oxygen inspiratory fraction (FIO2) variations. Values are provided as mean ± STD; VT, tidal volume; R, different values of resistance were applied (5, 10 and 20 cm H2O/L/s) in combination with different compliance (30, 70, 120 cm H2O/L); dotted line represents the 10% accuracy range and the hashed line the 5% accuracy range; for VT variations according to R, a P-value equal to or below 0.05 was considered significant; *P <0.05; **P <0.005. VT accuracy according to FIO2 variations was correct for all ICU-like and sophisticated emergency and transport ventilators (ETV). However, most simple and mass casualty/military ETV depicted a significant Venturi effect with a decrease in VT while switching from FIO2 100% to Air-Mix. Moreover, clinicians might be aware that the FIO2 value in the Air-Mix setting greatly differed from one device to the other (from 45 to 86%).
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
getmorefigures.php?uid=PMC4197290&req=5

Fig3: Tidal volume accuracy according to oxygen inspiratory fraction (FIO2) variations. Values are provided as mean ± STD; VT, tidal volume; R, different values of resistance were applied (5, 10 and 20 cm H2O/L/s) in combination with different compliance (30, 70, 120 cm H2O/L); dotted line represents the 10% accuracy range and the hashed line the 5% accuracy range; for VT variations according to R, a P-value equal to or below 0.05 was considered significant; *P <0.05; **P <0.005. VT accuracy according to FIO2 variations was correct for all ICU-like and sophisticated emergency and transport ventilators (ETV). However, most simple and mass casualty/military ETV depicted a significant Venturi effect with a decrease in VT while switching from FIO2 100% to Air-Mix. Moreover, clinicians might be aware that the FIO2 value in the Air-Mix setting greatly differed from one device to the other (from 45 to 86%).

Mentions: No effect was observed in the ICU-like and sophisticated ETV categories, while in the simple and mass-casualty/military categories it induced significant impact on VT for most devices (Figure 3).Figure 3


Bench-test comparison of 26 emergency and transport ventilators.

L'Her E, Roy A, Marjanovic N - Crit Care (2014)

Tidal volume accuracy according to oxygen inspiratory fraction (FIO2) variations. Values are provided as mean ± STD; VT, tidal volume; R, different values of resistance were applied (5, 10 and 20 cm H2O/L/s) in combination with different compliance (30, 70, 120 cm H2O/L); dotted line represents the 10% accuracy range and the hashed line the 5% accuracy range; for VT variations according to R, a P-value equal to or below 0.05 was considered significant; *P <0.05; **P <0.005. VT accuracy according to FIO2 variations was correct for all ICU-like and sophisticated emergency and transport ventilators (ETV). However, most simple and mass casualty/military ETV depicted a significant Venturi effect with a decrease in VT while switching from FIO2 100% to Air-Mix. Moreover, clinicians might be aware that the FIO2 value in the Air-Mix setting greatly differed from one device to the other (from 45 to 86%).
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4197290&req=5

Fig3: Tidal volume accuracy according to oxygen inspiratory fraction (FIO2) variations. Values are provided as mean ± STD; VT, tidal volume; R, different values of resistance were applied (5, 10 and 20 cm H2O/L/s) in combination with different compliance (30, 70, 120 cm H2O/L); dotted line represents the 10% accuracy range and the hashed line the 5% accuracy range; for VT variations according to R, a P-value equal to or below 0.05 was considered significant; *P <0.05; **P <0.005. VT accuracy according to FIO2 variations was correct for all ICU-like and sophisticated emergency and transport ventilators (ETV). However, most simple and mass casualty/military ETV depicted a significant Venturi effect with a decrease in VT while switching from FIO2 100% to Air-Mix. Moreover, clinicians might be aware that the FIO2 value in the Air-Mix setting greatly differed from one device to the other (from 45 to 86%).
Mentions: No effect was observed in the ICU-like and sophisticated ETV categories, while in the simple and mass-casualty/military categories it induced significant impact on VT for most devices (Figure 3).Figure 3

Bottom Line: Leak compensation in most ICU-like and 4/10 sophisticated devices was able to correct at least partially for system leaks, but with variations among ventilators.Major differences were observed between devices and categories, either in terms of general characteristics or technical reliability, across the spectrum of operation.Huge variability of tidal volume delivery with some devices in response to modifications in respiratory mechanics and FIO2 should make clinicians question their use in the clinical setting.

View Article: PubMed Central - PubMed

ABSTRACT

Introduction: Numerous emergency and transport ventilators are commercialized and new generations arise constantly. The aim of this study was to evaluate a large panel of ventilators to allow clinicians to choose a device, taking into account their specificities of use.

Methods: This experimental bench-test took into account general characteristics and technical performances. Performances were assessed under different levels of FIO2 (100%, 50% or Air-Mix), respiratory mechanics (compliance 30,70,120 mL/cmH2O; resistance 5,10,20 cmH2O/mL/s), and levels of leaks (3.5 to 12.5 L/min), using a test lung.

Results: In total 26 emergency and transport ventilators were analyzed and classified into four categories (ICU-like, n = 5; Sophisticated, n = 10; Simple, n = 9; Mass-casualty and military, n = 2). Oxygen consumption (7.1 to 15.8 L/min at FIO2 100%) and the Air-Mix mode (FIO2 45 to 86%) differed from one device to the other. Triggering performance was heterogeneous, but several sophisticated ventilators depicted triggering capabilities as efficient as ICU-like ventilators. Pressurization was not adequate for all devices. At baseline, all the ventilators were able to synchronize, but with variations among respiratory conditions. Leak compensation in most ICU-like and 4/10 sophisticated devices was able to correct at least partially for system leaks, but with variations among ventilators.

Conclusion: Major differences were observed between devices and categories, either in terms of general characteristics or technical reliability, across the spectrum of operation. Huge variability of tidal volume delivery with some devices in response to modifications in respiratory mechanics and FIO2 should make clinicians question their use in the clinical setting.

Show MeSH