Ventilator Hyperinflation and Hemodynamics

Not Applicable

Completed

• Conditions: Respiratory Disorders; Respiratory Failure
• Interventions: Device: VHI Without Inspiratory Pause; Device: VHI With Inspiratory Pause; Device: Baseline Mechanical Ventilation

• Registration Number: NCT03557645
• Lead Sponsor: Centro Universitário Augusto Motta

Brief Summary

Ventilator hyperinflation (VHI) has been shown to be effective in improving respiratory mechanics, secretion removal, and gas exchange in mechanically ventilated patients; however, the literature is scarce concerning its safety and adverse effects. Thus, the aim of this study is to compare the hemodynamic repercussions of VHI in volume-controlled mode. In a randomized, controlled and crossover design, 24 mechanically ventilated patients will undergo 2 modes of ventilator hyperinflation (with and without an inspiratory pause) and a control intervention. Cardiac output, cardiac index, mean arterial pressure, pulmonary vascular resistance, systolic volume and other hemodynamic variables will be recorded during the interventions.

Detailed Description

Background: ventilator hyperinflation (VHI) has been shown to be effective in improving respiratory mechanics, secretion removal, and gas exchange in mechanically ventilated patients; however, the literature is scarce concerning its safety and adverse effects. Thus, the aim of this study is to compare the hemodynamic repercussions of VHI in volume-controlled mode.

Methods: in a randomized, controlled and crossover design, 24 mechanically ventilated patients will undergo 2 modes of ventilator hyperinflation (with and without an inspiratory pause of 2 seconds) and a control intervention. For the VHI interventions, the inspiratory flow will be set at 20 Lpm, and tidal volume will be increased until a peak pressure of 40cmH2O is achieved. During the control intervention, the patients will remain in volume-control ventilation with an inspiratory flow = 60Lpm and tidal volume = 6mL/IBW. The interval between interventions (washout) will be of 10 minutes or more, according to the time needed to recover the cardiac index to baseline values (maximum difference of 10%). Cardiac output, cardiac index, mean arterial pressure, pulmonary vascular resistance, systolic volume and other hemodynamic variables will be recorded during the interventions by using impedance cardiography.

Study Timeline

• Study Start: 2017-11-05
• Study First Submitted: 2018-05-13
• Study First Submitted QC: 2018-06-04
• Study First Posted: 2018-06-15
• Primary Completion: 2018-09-20
• Study Completion: 2018-09-30
• Status Verified: 2020-08
• Last Update Submitted: 2020-08-12
• Last Update Posted: 2020-08-14

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 17

Inclusion Criteria

• Patients under mechanical ventilation for more than 48h

Exclusion Criteria

• mucus hypersecretion (defined as the need for suctioning < 2-h intervals),
• absence of respiratory drive,
• atelectasis,
• severe bronchospasm,
• positive end expiratory pressure > 10cmH2O,
• PaO2-FiO2 relationship < 150,
• mean arterial pressure < 60mmHg,
• inotrope requirement equivalent to >15 ml/h total of adrenaline and noradrenalin,
• intracranial pressure > 20mmHg

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
VHI Without Inspiratory Pause	VHI Without Inspiratory Pause	Application of a ventilator hyperinflation intervention with Volume Control Continuous Mandatory Ventilation (VC-CMV). The inspiratory flow will be set at 20Lpm and the tidal volume will be increased in steps of 200mL until the peak airway pressure of 40cmH2O is achieved. After achieving the target pressure, this ventilatory regimen will last 15 minutes. Positive end-expiratory pressure and the inspired oxygen fraction will not be modified.
VHI With Inspiratory Pause	VHI With Inspiratory Pause	Application of a ventilator hyperinflation intervention with Volume Control Continuous Mandatory Ventilation (VC-CMV). The inspiratory flow will be set at 20Lpm, the tidal volume will be increased in steps of 200mL until the peak airway pressure of 40cmH2O is achieved, and an inspiratory pause will be applied at the end of inspiration. After achieving the target pressure, this ventilatory regimen will last 15 minutes. Positive end-expiratory pressure and the inspired oxygen fraction will not be modified.
Baseline Mechanical Ventilation	Baseline Mechanical Ventilation	The subjects will be kept in Volume Control Continuous Mandatory Ventilation (VC-CMV) with an inspiratory flow = 60Lpm and tidal volume = 6mL/IBW. Positive end-expiratory pressure and the inspired oxygen fraction will not be modified.

Primary Outcome Measures

Name	Time	Method
Change in Cardiac Output	Baseline (before) and 10 minutes after the onset of VHI modesBasel	Estimation of cardiac output variation using thoracic bioimpedance

Secondary Outcome Measures

Name	Time	Method
Change in Systolic Volume II	Baseline (before) and 5 minutes after the end of VHI modes	Estimation of systolic volume variation using thoracic bioimpedance
Change in Vascular pulmonary resistance	Baseline (before) and 10 minutes after the onset of VHI modes	Estimation of vascular pulmonary resistance variation using thoracic bioimpedance
Change in Mean Arterial Pressure	Baseline (before) and 10 minutes after the onset of VHI modes	Recording of mean arterial pressure variation using an automatic noninvasive device
Change in Cardiac Index II	Baseline (before) and 5 minutes after the end of VHI modes	Estimation of cardiac index variation using thoracic bioimpedance
Change in Vascular pulmonary resistance II	Baseline (before) and 5 minutes after the end of VHI modes	Estimation of vascular pulmonary resistance variation using thoracic bioimpedance
Change in Mean Arterial Pressure II	Baseline (before) and 5 minutes after the end of VHI modes	Recording of mean arterial pressure variation using an automatic noninvasive device
Change in Cardiac Index	Baseline (before) and 10 minutes after the onset of VHI modes	Estimation of cardiac index variation using thoracic bioimpedance
Change in Systolic Volume	Baseline (before) and 10 minutes after the onset of VHI modes	Estimation of systolic volume variation using thoracic bioimpedance
Change in Cardiac Output II	Baseline (before) and 5 minutes after the end of VHI modes	Estimation of cardiac output variation using thoracic bioimpedance

Trial Locations

Locations (1)

Hospital Santa Martha; 🇧🇷 Niterói, Rio De Janeiro, Brazil