Alveolar Recruitment Maneuvers on Reduction of Lung Atelectasis in Bariatric Surgery by Using Lung Ultrasound Score

The study aims to compare the staircase alveolar recruitment maneuver with PEEP titration versus sustained inflation alveolar recruitment maneuver by using lung ultrasound score as an indicator of improving lung atelectasis in bariatric surgery

Inclusion Criteria:Adult morbidly obese patients (Body mass index < 40kg / m2 or Body mass index < 35kg / m2 with obesity-related comorbidities such as hypertension, diabetes, and sleep apnea)undergo elective bariatric laparoscopic surgery with an expected duration of at least one hour under general anesthesia.Exclusion Criteria:Patient refusal to participate in the study.Patients with a previous history of thoracic surgery.Patients with a history of chest disease (COPD, emphysema, or pneumothorax).Patients with abnormal pre-operative chest radiographs such as pneumonia, pleural effusion.Patients with heart failure or impending failure.Patients with known hypovolemia.Patients with increased intracranial pressure.