Relationship Between Atelectasis on Ultrasound and PaO2/FiO2

Study Overview
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Brief Summary
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The aim of this study is to find out relationship between PaO2/FiO2 and atelectasis finding on intraoperative lung ultrasound.

Detailed Description
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Patients aged 20 65 with ASA class (American Society of Anesthesiologists physical status classification) 1 or 2 who are scheduled to undergo general anesthesia by using endotracheal intubation and arterial line cannulation will participate in this study. The patients with abnormal chest x-ray finding, pregnancy, arrhythmia, ischemic heart disease will be excluded from this study as well as the patients who are scheduled to undergo lung or heart surgery. After 5 minutes preoxygenation, patients will be monitored with pulse oxymetry, noninvasive blood pressure. General anesthesia will be proceeded with typical method and endotracheal intubation and arterial cannulation will be proceeded. After ventilator adjustment (tidal volume as 8 times of the patient's ideal body weight), airway pressures(peak and plateau) will be recorded. Subsequently, arterial blood sampling will be proceeded while examination of the atelectasis findings on lung ultrasound before surgery. Lung ultrasound examination will be proceeded on 6 sections of patient's basal segments of the lung, including anterior, lateral, posterior segment. Juxtapleural consolidation, loss of A lines, presence of B lines, air bronchogram, loss of sliding sign and presence of pulse sign on lung ultrasound finding will be investigated and recorded. Same ultrasound examination and arterial blood sampling will be followed after surgery ends. The results of PaO2/FiO2 on arterial blood samplings will be compared with findings on lung ultrasound before and after surgery.

Official Title
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Relationship Between Intraoperative Atelectasis Findings on Transthoracic Lung Ultrasound and PaO2/FiO2

Conditions
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Atelectasis, Postoperative

Intervention / Treatment
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* Device: ultrasound


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients aged 20 65 with ASA class 1 or 2 who are scheduled to undergo general anesthesia by using endotracheal intubation and arterial line cannulation Exclusion Criteria: The patients with abnormal chest x-ray finding, pregnancy, arrhythmia, ischemic heart disease

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 65 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: Diagnostic
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Study participants<br>After general anesthesia development of the atelectasis will be investigated by the lung ultrasound | Device: ultrasound<br>* Juxtapleural consolidation, loss of A lines, presence of B lines, air bronchogram, loss of sliding sign and presence of pulse sign on lung ultrasound finding will be investigated and recorded.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Intraoperative lung ultrasound for atelectasis | Lung ultrasound examination for atelectasis findings (eg. whether there is a loss of A line or presence of B lines before and after surgery) | Baseline (Before surgery begins) and Postoperative (Just after the surgery ends) | 
| Change in PaO2/FiO2 | Arterial blood sampling to find out whether their is a change in PaO2/FiO2 before and after surgery. | Baseline (Before surgery begins) and Postoperative (Just after the surgery ends) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Airway pressure change | To find out if there is any difference between preoperative and postoperative airway pressures(peak and plateau pressure), monitored by ventilator used during general anesthesia in mmHg | Baseline (Before surgery begins) and Postoperative (Just after the surgery ends) | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Atelectasis, Postoperative, Lung ultrasound