Oxygen Concentration During Alveolar Recruitment

Study Overview
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Brief Summary
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The purpose of this study is to investigate the effect of oxygen concentration during alveolar recruitment on absorption ateletasis.

Official Title
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The Effect of Oxygen Concentration During Alveolar Recruitment on Absorption Atelectasis

Conditions
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Atelectasis, Postoperative Pulmonary

Intervention / Treatment
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* Procedure: FiO2_1.0
* Procedure: FiO2_0.4


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients undergoing laparoscopic obstetric or colon surgery with Trendelenburg position Exclusion Criteria: American Society of Anesthesiologists physical status IV or more Severe cardiovascular disease Severe chronic obstructive pulmonary disease, emphysema History of pneumothorax, bullae History of lung resection surgery Conversion to laparotomy Refusal to participate

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 70 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: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: FiO2_1.0<br>Alveolar recruitment is performed with 100% oxygen concentration at specific time points. | Procedure: FiO2_1.0<br>* Alveolar recruitment is performed with 100% oxygen concentration after general anesthesia induction, after position change to Trendelenburg, after position change to supine, and at the end of operation.<br>|
| Experimental: FiO2_0.4<br>Alveolar recruitment is performed with 40% oxygen concentration at specific time points. | Procedure: FiO2_0.4<br>* Alveolar recruitment is performed with 40% oxygen concentration after general anesthesia induction, after position change to Trendelenburg, after position change to supine, and at the end of operation.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Modified lung ultrasound score | The score is calculated by adding up the 12 individual quadrant scores assessed using lung ultrasound. Each quadrant score ranges from 0 (minimal atelectasis) 3 (severe atelectasis), so the maximum total score is 36. | Intraoperative (at the end of operation, before emergence) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Modified lung ultrasound score | The score is calculated by adding up the 12 individual quadrant scores assessed using lung ultrasound. Each quadrant score ranges from 0 (minimal atelectasis) 3 (severe atelectasis), so the maximum total score is 36. | Postoperative 30 minutes | 
| Intraoperative desaturation | Oxygen saturation by pulse oximetry <95% | Intraoperative | 
| Intraoperative partial pressure of arterial oxygen/fraction of inspired oxygen ratio | Partial pressure of arterial oxygen/fraction of inspired oxygen ratio | Intraoperative (20minutes after each recruitment) | 
| Postoperative partial pressure of arterial oxygen/fraction of inspired oxygen ratio | Partial pressure of arterial oxygen/fraction of inspired oxygen ratio | Postoperative 30 minutes | 
| Postoperative pulmonary complication | respiratory infection, respiratory failure, pleural effusion, atelectasis, pneumothorax, atelectasis, bronchospasm, aspiration pneumonitis | Postoperative 24 hours | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Absorption atelectasis, Lung sono, Oxygen concentration