Functional Residual Capacity (FRC) Guided Alveolar Recruitment Strategy

Study Overview
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Brief Summary
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In ventilated patients open endotracheal suctioning may lead to alveolar derecruitment, which can be monitored by means of functional residual capacity (FRC) measurements. The investigators hypothesized that a recruitment strategy based on FRC measurements would improve oxygenation and regional ventilation after an open endotracheal suctioning manoeuvre.

Detailed Description
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In mechanically ventilated patients the functional residual capacity will be measured before (baseline) and after an open endotracheal suctioning manoeuvre. Based on these changes patients will be divided into two groups: Group A with more than 94% of baseline FRC, and Group B with less than 94% of baseline FRC. Both groups will be randomized to receive an alveolar recruitment manoeuvre or no alveolar recruitment manoeuvre, leading to four groups. Oxygenation and regional ventilation with electrical impedance tomography will be studied.

Official Title
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The Influence of a Functional Residual Capacity Guided Alveolar Recruitment Strategy After Open Endotracheal Suctioning on Oxygenation and Regional Ventilation

Conditions
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Ventilation, Functional Residual Capacity

Intervention / Treatment
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* Procedure: Alveolar recruitment manoeuvre


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: ventilated after elective cardiac surgery Exclusion Criteria: hemodynamic instability (eg. intraaortic balloon pump) acute lung injury, i.e. PEEP > 10cmH20 or FiO2 > 0.4

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: Supportive Care
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Group A_RM<br>Patients with FRC after open endotracheal suctioning of more than 94% of baseline randomized to receive an alveolar recruitment manoeuvre. | Procedure: Alveolar recruitment manoeuvre<br>* Increase airway pressure during pressure controlled ventilation up to peak-airway pressure of 40 cmH20 and PEEP of 15 cmH20.<br>|
| No Intervention: Group A_NRM<br>Patients with FRC after open endotracheal suctioning of more than 94% of baseline randomized to receive no alveolar recruitment manoeuvre. | |
| Experimental: Group B_RM<br>Patients with FRC after open endotracheal suctioning of less than 94% of baseline randomized to receive an alveolar recruitment manoeuvre. | Procedure: Alveolar recruitment manoeuvre<br>* Increase airway pressure during pressure controlled ventilation up to peak-airway pressure of 40 cmH20 and PEEP of 15 cmH20.<br>|
| No Intervention: Group B_NRM<br>Patients with FRC after open endotracheal suctioning of less than 94% of baseline randomized to receive no alveolar recruitment manoeuvre. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Arterial oxygenation |  | 60 minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Regional ventilation |  | 60 minutes |