Closed-Loop Control of Respiratory Drive Using Pressure-Support Ventilation

Background: Patient-ventilator asynchrony is common during pressure support ventilation (PSV) because of the constant cycling-off criteria and variation of respiratory system mechanical properties in individual patients. Automatic adjustment of inspiratory triggers and cycling-off criteria based on waveforms might be a useful tool to improve patient-ventilator asynchrony during PSV.Method: Twenty-four patients were enrolled and were ventilated using PSV with different cycling-off criteria of 10% (PS10), 30% (PS30), 50% (PS50), and automatic adjustment PSV (PSAUTO). Patient-ventilator interactions were measured.Results: The total asynchrony index (AI) and NeuroSync index were consistently lower in PSAUTO when compared with PS10, PS30, and PS50, (P < 0.05). The benefit of PSAUTO in reducing the total AI was mainly because of the reduction of the micro-AI but not the macro-AI. PSAUTO significantly improved the relative cycling-off error when compared with prefixed controlled PSV (P < 0.05). PSAUTO significantly reduced the trigger error and inspiratory effort for the trigger when compared with a prefixed trigger. However, total inspiratory effort, breathing patterns, and respiratory drive were not different among modes.Conclusions: When compared with fixed cycling-off criteria, an automatic adjustment system improved patient-ventilator asynchrony without changes in breathing patterns during PSV. The automatic adjustment system could be a useful tool to titrate more personalized mechanical ventilation.

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Adaptive support ventilation with and without end-tidal CO2 closed loop control versus conventional ventilation

Intensive Care Medicine ◽

10.1007/s00134-012-2742-6 ◽

2012 ◽

Vol 39 (4) ◽

pp. 703-710 ◽

Cited By ~ 6

Author(s):

Demet S. Sulemanji ◽

Andrew Marchese ◽

Marc Wysocki ◽

Robert M. Kacmarek

Keyword(s):

Closed Loop ◽

Conventional Ventilation ◽

Closed Loop Control ◽

Loop Control ◽

Adaptive Support Ventilation ◽

Support Ventilation ◽

Control Versus ◽

Adaptive Support ◽

End Tidal ◽

End Tidal Co2

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Effects of Propofol on Respiratory Drive and Patient-ventilator Synchrony during Pressure Support Ventilation in Postoperative Patients

Chinese Medical Journal ◽

10.4103/0366-6999.205864 ◽

2017 ◽

Vol 130 (10) ◽

pp. 1155-1160 ◽

Cited By ~ 5

Author(s):

Ling Liu ◽

Ai-Ping Wu ◽

Yi Yang ◽

Song-Qiao Liu ◽

Ying-Zi Huang ◽

...

Keyword(s):

Pressure Support Ventilation ◽

Pressure Support ◽

Respiratory Drive ◽

Support Ventilation ◽

Ventilator Synchrony

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Pressure support ventilation

10.1093/med/9780199600830.003.0097 ◽

2016 ◽

Author(s):

Hérnan Aguirre-Bermeo ◽

Jordi Mancebo

Keyword(s):

Mechanical Ventilation ◽

Pressure Support Ventilation ◽

Pressure Support ◽

Closed Loop ◽

Threshold Level ◽

Comfort Zone ◽

Gradual Reduction ◽

Support Ventilation ◽

Breathing Effort ◽

Levels Of Support

Pressure support ventilation (PSV) is one of the most common ventilatory modalities used in intensive care units. PSV is an assisted, pressure-limited, and flow-cycled ventilatory mode. The ventilator provides assistance when the patient makes a breathing effort, and when inspiratory flow reaches a certain threshold level, cycling to exhalation occurs. PSV unloads respiratory muscle effort, while allowing the patient to retain control over the respiratory rate and tidal volume. Withdrawal from mechanical ventilation should be performed with a gradual reduction of levels of support until extubation. Asynchronies can be present during PSV and are typically associated with high levels of support. A closed-loop modality, which adjusts support levels to keep the patient in a ‘comfort zone’, has been designed to assist in the withdrawal of mechanical ventilation. It performs at least as well as experienced medical staff and could be useful in specific groups of patients.

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The Impact of Visual Feedback Type on the Mastery of Visuo-Motor Transformations

Zeitschrift für Psychologie ◽

10.1027/2151-2604/a000084 ◽

2012 ◽

Vol 220 (1) ◽

pp. 3-9 ◽

Cited By ~ 4

Author(s):

Sandra Sülzenbrück

Keyword(s):

Empirical Research ◽

Visual Feedback ◽

Closed Loop ◽

Motor Planning ◽

Visual Input ◽

Closed Loop Control ◽

Loop Control ◽

Feedback Type ◽

Effective Use ◽

The Impact

For the effective use of modern tools, the inherent visuo-motor transformation needs to be mastered. The successful adjustment to and learning of these transformations crucially depends on practice conditions, particularly on the type of visual feedback during practice. Here, a review about empirical research exploring the influence of continuous and terminal visual feedback during practice on the mastery of visuo-motor transformations is provided. Two studies investigating the impact of the type of visual feedback on either direction-dependent visuo-motor gains or the complex visuo-motor transformation of a virtual two-sided lever are presented in more detail. The findings of these studies indicate that the continuous availability of visual feedback supports performance when closed-loop control is possible, but impairs performance when visual input is no longer available. Different approaches to explain these performance differences due to the type of visual feedback during practice are considered. For example, these differences could reflect a process of re-optimization of motor planning in a novel environment or represent effects of the specificity of practice. Furthermore, differences in the allocation of attention during movements with terminal and continuous visual feedback could account for the observed differences.

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