DID YOU KNOW? - Draeger · DID YOU KNOW? What is it? Which are the settings? Variable Pressure...
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VARIABLE PRESSURE SUPPORT VENTILATION DID YOU KNOW? What is it? Which are the settings? Variable Pressure Support works like a pressure support ventilation mode with an additional setting: variability of PS (in %) . The pressure support level set by the user is kept in average with a random probability variation of the pressure support level based on statistic distribution. In addition to the normal Pressure Support settings, when Variable Pressure Support is active, the Pressure variability knob is available . With this parameter it’s possible to set the variability of the PS support level from 0% (no variability) to 100% (maximum variability). Why is it helpful to improve outcome? Variable Pressure support can be applied to any patient in spontaneous breathing to mimic the natural variability of tidal volume in healthy subjects (approximately 33% of the tidal volume at rest 1 ). This variability may be beneficial to improve function and reduce damage in the diseased lung mainly thanks to these effects 2 : • Reduction of inspiratory WOB • Improvement in patient/ventilator synchrony • Increase in the variability of respiratory pattern • Weaning from mechanical ventilator The pressure support level is averaged on the PS settings but varied using Variability setting 1. Breathing pattern in humans: Diversity and individuality, Benchetrit, 2000; Multifractility in human heartbeat dynamics nature, Ivanov, 1999 2. Variable ventilation from bench to bedside — Huhle et al. Critical Care (2016) 20:62 3. Short-term effects of noisy pressure support ventilation in patients with acute hypoxemic respiratory failure - Spieth et al. - Critical Care201317:R261 4. Rationale and study design of ViPS — variable pressure support for weaning from mechanical ventilation: Study protocol for an international multicenter randomized controlled open trial – 2013 5. Comparative Effects Of Variable Pressure Support, Neurally Adjusted Ventilatory Assist (NAVA) And Proportional Assist Ventilation (PAV) On The Variability Of The Breathing Pattern And On Patient Ventilator Interaction – Morawiec et al. - Réanimation (2014) 24:S22–S25 Example: “In the very short term, noisy PSV proved safe and feasible in patients with acute hypoxemic respiratory failure. Compared to conventional PSV, noisy PSV increased the variability of tidal volumes, and was associated with improved patient-ventilator synchrony, at comparable levels of gas exchange” 3 “ViPS is the forst randomized controlled trial investigating whether variable, compared to nonvariable PSV, shortens the duration of weaning from mechanicals ventilation in a mixed population of critically ill patients. This trial aims to determine the role of variable PSV in the intesive care unit” 4 “V-PSV80 (Variable pressure ventilation with 80% of variability) includes the same increase in breathing pattern variability than NAVA, without inducing more patient-ventilator asynchrony or lung over distention ” 5 1σ 2σ 3σ ‒3σ 0.1% 0.1% 2.1% 2.1% 34.1% 34.1% 13.6% 13.6% ‒2σ ‒1σ μ The set PS level has a higher probability of being delivered Higher level of the set PS have lower probability of being delivered Lower level of the set PS have lower probability of being delivered Every spontaneous breath is supported with a different level of pressure. The level of pressure depends on the set variability and on the stochastic distribution. PEEP Paw Flow Settings Results ∆ P supp PEEP Press. Var . 10 cmH2O 5 cmH2O 50% 15 cmH2O 10 cmH2O 20 cmH2O P supp P supp min P supp max EXPIRATION P t EXPIRATION INSPIRATION INSPIRATION
Transcript of DID YOU KNOW? - Draeger · DID YOU KNOW? What is it? Which are the settings? Variable Pressure...
VARIABLE PRESSURE SUPPORT VENTILATION
DID YOU KNOW?
What is it?
Which are the settings?
Variable Pressure Support works like a pressure support ventilation mode with an additional setting: variability of PS (in %).The pressure support level set by the user is kept in average with a random probability variation of the pressure support level based on statistic distribution.
In addition to the normal Pressure Support settings, when Variable Pressure Support isactive, the Pressure variability knob is available.With this parameter it’s possible to set the variability of the PS support level from 0%(no variability) to 100% (maximum variability).
Why is it helpful to improve outcome?
Variable Pressure support can be applied to any patient in spontaneous breathing to mimic the natural variability of tidal volume in healthy subjects (approximately 33% of the tidal volume at rest1 ).This variability may be beneficial to improve function and reduce damage in the diseased lung mainly thanks to these effects2:
• Reduction of inspiratory WOB • Improvement in patient/ventilator synchrony • Increase in the variability of respiratory pattern • Weaning from mechanical ventilator
The pressure support level is averaged on the PS settings but varied using Variability setting
1. Breathing pattern in humans: Diversity and individuality, Benchetrit, 2000; Multifractility in human heartbeat dynamics nature, Ivanov, 19992. Variable ventilation from bench to bedside — Huhle et al. Critical Care (2016) 20:623. Short-term effects of noisy pressure support ventilation in patients with acute hypoxemic respiratory failure - Spieth et al. - Critical Care201317:R2614. Rationale and study design of ViPS — variable pressure support for weaning from mechanical ventilation: Study protocol for an international multicenter randomized controlled open trial – 20135. Comparative Effects Of Variable Pressure Support, Neurally Adjusted Ventilatory Assist (NAVA) And Proportional Assist Ventilation (PAV) On The Variability Of The Breathing Pattern And On Patient Ventilator Interaction – Morawiec et al. - Réanimation (2014) 24:S22–S25
Example:
“In the very short term, noisy PSV proved safe and feasible in patients with acute hypoxemic respiratory failure. Compared to conventional PSV, noisyPSV increased the variability of tidal volumes, and was associated with improved patient-ventilator synchrony, at comparable levels of gas exchange” 3
“ViPS is the forst randomized controlled trial investigating whether variable, compared to nonvariable PSV, shortens the duration of weaning from mechanicals ventilation in a mixed population of critically ill patients. This trial aims to determine the role of variable PSV in the intesive care unit” 4
“V-PSV80 (Variable pressure ventilation with 80% of variability) includes the same increase in breathing pattern variability than NAVA, without inducing more patient-ventilator asynchrony or lung over distention” 5
1σ 2σ 3σ‒3σ
0.1% 0.1%2.1% 2.1%
34.1%34.1%
13.6% 13.6%
‒2σ ‒1σ µ
The set PS level has a higher probability of being delivered
Higher level of the set PShave lower probability ofbeing delivered
Lower level of the set PShave lower probability ofbeing delivered
Every spontaneous breath is supported with a different level of pressure.The level of pressure depends on the set variability and on the stochastic distribution.
PEEP
Paw
Flow
Settings Results∆ Psupp
PEEP
Press. Var.
10 cmH2O
5 cmH2O
50%
15 cmH2O
10 cmH2O
20 cmH2O
Psupp
Psupp min
Psupp max
EXPIRATION
P
t
EXPIRATIONINSPIRATION INSPIRATION
