Ultrasound-guided Alveolar Recruitment in Laparoscopic Gynecological Surgery

Study Overview
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Brief Summary
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The study aims to compare the degree of atelectasis between ultrasound-guided alveolar recruitment group and conventional alveolar recruitment group in patients receiving laparoscopic gynecologic surgery

Official Title
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The Effect of Ultrasound-guided Alveolar Recruitment on Postoperative Atelectasis in Patients Receiving Laparoscopic Gynecological Surgery

Conditions
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Pulmonary Atelectasis

Intervention / Treatment
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* Procedure: lung ultrasound-guided alveolar recruitment
* Procedure: conventional alveolar recruitment


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adult patients scheduled to undergo elective laparoscopic gynecological surgery (laparoscopic ovarian cystectomy or laparoscopic salpingo-oophorectomy or laparoscopic hysterectomy or laparoscopic myomectomy) under general anesthesia, with ASA physical status classification I or II Exclusion Criteria: Previous history of lung surgery Patients having pneumonia, pneumothorax, or pleural effusion in preoperative chest X-ray Patients with COPD, emphysema Patients with previous history of pneumothorax, or bullae Morbid cardiac disease Adolescent aged < 18 years Anticipated duration of surgery < 1 hour

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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Female

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: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: LUS-guided alveolar recruitment<br>Lung ultrasound-guided alveolar recruitment maneuver will be performed | Procedure: lung ultrasound-guided alveolar recruitment<br>* Alveolar recruitment maneuver will be performed under lung ultrasound-guidance. Positive pressure will be not exceed 40cmH2O and duration of positive pressure inflation will not exceed 10 seconds.<br>|
| Active Comparator: conventional alveolar recruitment<br>Alveolar recruitment maneuver will be provided with positive pressure of 30 cmH2O for 10 seconds. | Procedure: conventional alveolar recruitment<br>* Alveolar recruitment will be provided with positive pressure of 30cmH2O for 10 seconds<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| modified lung ultrasound score at the end of surgery | Both lung ultrasound scores can be calculated by adding up the 12 individual pulmonary quadrant scores yielding a score between 0 (no aeration loss) and 36 (complete aeration loss). | At the end of surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| modified lung ultrasound score at post-anesthesia care unit (PACU) | Both lung ultrasound scores can be calculated by adding up the 12 individual pulmonary quadrant scores yielding a score between 0 (no aeration loss) and 36 (complete aeration loss). | intraoperative | 
| incidence of atelectasis diagnosed by ultrasonography | the presence of atelectasis by ultrasonography | intraoperative | 
| arterial blood gas analyses | PaO2, PaCO2, SaO2, O2 index (PaO2/FiO2) | intraoperative | 
| incidence of postoperative complications | fever, pneumonia, atelectasis diagnosed by chest X-ray | during the postoperative period until discharge from hospital, an average of 3 days | 
| intraoperative mean arterial pressure | mean arterial pressure in mmHg | intraoperative | 
| intraoperative SpO2 | SpO2 in % | intraoperative | 
| intraoperative peak airway pressure | peak airway pressure in cmH2O | intraoperative | 
| Incidence of postoperative shoulder pain at POD #1 | patients will be asked whether they have shoulder pain or not, using NRS (0 to 10) scale | assessed at postoperative day 1 |