Comparison Between Different Ventilator Hyperinflation Maneuvers

Study Overview
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Brief Summary
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The hyperinflation ventilator was performed in different modalities and ventilatory adjustments, with total pressure of 40cmH2O. The inspiratory volume, inspiratory time, mean airway pressure, inspiratory and expiratory flow, and bias flow were evaluated.

Detailed Description
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PURPOSE: To compare different ways of applying ventilator hyperinflation. METHODS: A randomized crossover clinical trial was performed with 30 patients (66.5 ± 17.3 years) with hypersecretion. The ventilator hyperinflation was performed in five ventilatory modalities for five minutes, with an interval of 2 hours, the order being determined by randomization: controlled ventilation at volume (VCV) with constant flow of 20 (VCV20) Lpm and 40 Lpm (VCV40), controlled ventilation pressure ventilation (PCV), controlled pressure ventilation associated with inspiratory time adjustment (PCV + Tins) and support pressure ventilation (PSV). In VCV mode, the volume was increased every 50mL, until reaching a maximum pressure of 40cmH2O. In the pressure controlled modes, the inspiratory pressure was increased every 5 cmH2O until the total pressure reached 40 cmH2O. The inspiratory time was adjusted so that the inspiratory flow reached the baseline. The following variables were evaluated: tidal volume, inspiratory time (Tins), mean airway pressure (Pmean), peak inspiratory flow (PIFR) and expiratory flow (PEFR), PIFR / PEFR and Bias Flow (PEFR-PIFR).

Official Title
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Comparison Between Different Ventilator Hyperinflation Maneuvers

Conditions
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Infections, Respiratory, Ventilator Associated Pneumonia

Intervention / Treatment
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* Other: VCV20
* Other: VCV40
* Other: PCV
* Other: PCV+Tins
* Other: PSV


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Pulmonary infection Mechanically ventilated for more than 96 hours through pressure-assisted ventilation (PSV) or pressure-controlled ventilation (PCV) Static compliance between 30 and 70 mL/cmH2O PEEP between 5 and 8 cmH2O. Exclusion Criteria: Hemodynamic instability Non-drained pleural effusion or pneumothorax Intracranial hypertension Bronchospasm Adult respiratory distress syndrome (ARDS) Decompensated congestive heart failure

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Other
Allocation: Randomized
Intervention Model: Crossover Assignment
Interventional Model Description: In order to perform both interventions, the patients were placed in dorsal decubitus with a head elevated at 45 ° and submitted to closed tracheal aspiration, according to the recommendations of the American Association for Respiratory Care. In addition, the bacteriological filter was changed, the cuff pressure was increased and the presence of leaks in the mechanical fan circuits was verified. All patients underwent five hyperinflation maneuvers, the order being determined by randomization. Controlled volume ventilation (VCV) at a constant flow rate of 20 Lpm (VCV-20) and 40 Lpm (VCV-40), controlled pressure ventilation (VCV-40) was performed for 2 minutes at 10 minute intervals. PCV), pressure-controlled ventilation associated with inspiratory time adjustment (PCV + Tins) and pressure-supported ventilation (PSV). PEEP and FiO2 were maintained throughout the study.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: VCV20<br>Volume-controlled ventilation mode under constant flow of 20 Lpm. The inspired volume was progressively increased until the maximum pressure reached 40cmH2O. | Other: VCV20<br>* controlled volume ventilation mode under constant flow of 20 Lpm. The inspired volume was progressively increased until the Pmax reached 40cmH2O.<br>|
| Experimental: VCV40<br>Volume controlled ventilation mode under constant flow of 40 Lpm. The inspired volume was progressively increased until the maximum pressure reached 40cmH2O. | Other: VCV40<br>* volume controlled ventilation mode under constant flow of 40 Lpm. The inspired volume was progressively increased until the Pmax reached 40cmH2O.<br>|
| Experimental: PCV<br>Pressure controlled ventilation mode, inspiratory time of 1 second. The inspiratory pressure was increased every 5 cmH2O, until reaching the maximum pressure of 40 cmH2O. | Other: PCV<br>* controlled ventilation mode, 1 second inspiratory time. The inspiratory pressure was increased every 5 cmH2O, until reaching the maximum pressure of 40 cmH2O.<br>|
| Experimental: PCV+Tins<br>Pressure controlled ventilation mode and inspiratory pressure was increased every 5cmH2O, until the maximum pressure of 40 cmH2O was reached. The inspiratory time was gradually increased until the inspiratory flow reached the baseline. Concomitantly, the respiratory rate was decreased to allow the expiratory flow also to reach the baseline, to avoid self-PEEP. | Other: PCV+Tins<br>* controlled ventilation and inspiratory pressure was increased every 5 cmH2O until the maximum pressure was 40 cmH2O. The inspiratory time was gradually increased until the inspiratory flow reached the baseline. Concomitantly, the respiratory rate was decreased to allow the expiratory flow also to reach the baseline, to avoid self-PEEP.<br>|
| Experimental: PSV<br>Pressure support ventilation mode, with progressive increases of 5 cmH2O at inspiratory pressure, until reaching Pmax of 40 cmH2O. The expiratory sensitivity was adjusted by 25% for all patients. | Other: PSV<br>* ventilatory mode with pressure support, with progressive increases of 5 cmH2O at inspiratory pressure, until reaching Pmax of 40 cmH2O. The expiratory sensitivity was adjusted by 25% for all patients.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Inspiratory Volume | Inspiratory volume reached in each mode of ventilator hyperinflation, under a maximum pressure of 40cmH2O | Five minutes after the onset of intervention | 
| Inspiratory time | inspiratory time necessary for the inspiratory flow to reach the baseline or according to the settings of each modality | Five minutes after the onset of intervention | 
| Mean Pressure | airway mean pressure measured on the mechanical ventilator in 2 cycles | Five minutes after the onset of intervention | 
| Peak Expiratory Flow | maximal expiratory flow in 2 cycles | Five minutes after the onset of intervention | 
| Peak Inspiratory Flow | Maximal inspiratory flow in 2 cycles | Five minutes after the onset of intervention | 
| PIFR/PEFR | Peak inspiratory to expiratory flow ratio | Five minutes after the onset of intervention | 
| Bias Flow | Difference between peak inspiratory and expiratory flows | Five minutes after the onset of intervention | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Ventilator Hyperinflation, Physical Therapy, Mechanical Ventilation