Diagnostic Values of Lung Ultrasound for Perioperative Atelectasis

Study Overview
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Brief Summary
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Lung ultrasound offers a novel, reliable and radiation-free tool for diagnosing perioperative atelectasis and evaluating its severity in adult patients undergoing general anesthesia in the operating room.

Detailed Description
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Atelectases occur in up to 90% of patients undergoing general anesthesia and intubation. The aim of the present observational study was designed to further to evaluate the diagnostic performance of lung ultrasound (LUS) in detection of postoperative atelectasis in adult patients undergoing general anesthesia. Results of LUS as the experimental method will be compared to the results of computed tomography (CT) as the reference technique for the detection of atelectasis. The investigators want to confirm former findings of the appearance of perioperative atelectases and to prove that ultrasound is a valid tool for detection of atelectases.

Official Title
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Diagnostic Performance of Lung Ultrasound for Perioperative Atelectasis in Adult Patients Undergoing General Anesthesia

Conditions
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Postoperative Pulmonary Atelectasis

Intervention / Treatment
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* Device: lung ultrasound
* Radiation: thoracic computed tomography


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Aged 18 years and older; American Society of Anesthesiologists (ASA) physical status within class I-III; Scheduled for selective neurosurgical operation with general anesthesia; Need of mechanical ventilation more than 2 hours; Exclusion Criteria: Patients decline to participate; Pregnancy; Previous thoracic procedures (thoracic drain, thoracotomy, thoracoscopy); A history of pulmonary diseases within last two weeks with abnormal manifestation of lung CT (pulmonary parenchyma or/and interstitial lesions ); Pneumothorax or subcutaneous emphysema during peri-operation; Patients with a body mass index (BMI) more than 30 kg/m2; Emergency operation.

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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Arms and Interventions

| Intervention/Treatment |
| --- |
|Device: lung ultrasound|lung ultrasound investigations were performed right before and after the surgical procedure.|
|Radiation: thoracic computed tomography|thoracic CT were performed within one hour after the LUS investigation|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Correlation between manifestations of atelectasis in lung ultrasound and in thoracic computed tomography. | Measurements of lung ultrasound are performed before induction of anesthesia and immediately after finishing the surgery. Lung CTs are performed the day before surgery and within 1 hour after surgery. Outcome measure: comparison of atelectases by lung ultrasound (experimental method) versus by computed tomography (standard method) | From 5 minutes before induction of anesthesia to 1 hour after the surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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lung ultrasound, atelectasis, thoracic computed Tomography