This study aims to demonstrate the effects of automatic recruitment maneuver on peroperative lung mechanics of obese patients undergoing laparoscopic abdominal surgery.

128 obese patients undergoing abdominal laparoscopic surgery are randomly going to be assigned to automatic recruitment maneuver group and no recruitment maneuver group (control group). Both groups are going to be taken to the operating table. Electrocardiography (ECG), noninvasive blood pressure (NIBP), pulse oximeter and peripheral oxygen saturation (SpO2) and post-intubation end-tidal carbon dioxide (EtCO2) and train of four (TOF) monitoring will be performed. Then, general anesthesia induction procedure will be started. Following intubation, patients will be ventilated according to the ideal weight within the scope of intraoperative protective ventilation strategy and in pressure-controlled ventilation (PCV) mode. Then, automatic recruitment maneuver will be applied to the recruitment group twice, after insufflation and desufflation. It will not be applied to the control group. During recruitment maneuver, PEEP (Positive end-expiratory pressure), where dynamic compliance is measured highest, will be the ideal PEEP (Positive end-expiratory pressure) for the patient, and PEEP (Positive end-expiratory pressure) will be adjusted at this value after recruitment. If MAP (mean arterial pressure) is <60 mmHg during the maneuver, the maneuver will be terminated and these patients will be excluded from the study. Respiratory mechanics for both groups (peak pressure, plateau pressure, driver pressure, static compliance, dynamic compliance, EtCO2) and hemodynamic parameters (heart peak, mean arterial pressure, SpO2) at 5 different times (T1: post intubation; T2 : after insufflation; T3: 5 minutes after insufflation / after the first recruitment maneuver; T4: after desufflation; T5: 5 minutes after desufflation / after the second recruitment maneuver) will be recorded. Throughout the surgery, insufflation pressure will be kept as 10-13 cmH20. At the end of the surgery, the anesthesia maintenance of all patients will be terminated and the routine wake-up phase will be initiated. Creatinine values and hourly urine outputs of all patients routinely monitored at the postoperative 24th hour will be recorded on the case follow-up form.

Inclusion Criteria:

1. Patients between the ages of 18 and 65
2. Body mass index (BMI)> 30 patients undergoing laparoscopic abdominal surgery
3. ASA (American Society of Anesthesiologists) 2-3 patients

Exclusion Criteria:

1. Smokers
2. Patients with previous abdominal surgery
3. Patients with obstructive / restrictive lung disease,
4. Patients with coronary artery disease, heart failure
5. Patients with chronic kidney failure