Overview

This study is a prospective, single-center, single-blind, randomized controlled clinical trial. Patients scheduled for laparoscopic bariatric surgery will be selected and randomly assigned to either the EIT-guided individualized PEEP group (Group P-eit) or the control group (Group P-8). Group P will be ventilated using the PEEP value determined by EIT, while Group C will be ventilated with a fixed PEEP value of 8 cmH2O.The primary outcome is the incidence of postoperative pulmonary complications (PPCs) within 72 hours after surgery.

Eligibility

Inclusion Criteria:

1. Age between 18 and 65 years;
2. Plan to receive laparoscopic bariatric surgery under general anesthesia;
3. American Society of Anaesthesiologists (ASA) physical status I-III;
4. BMI between 30 and 55 kg/m2;
5. Voluntary participation in this study and signing of an informed consent form.

Exclusion Criteria:

1. History of smoking or previous thoracic surgery;
2. Invasive mechanical ventilation within 30 days;
3. Pregnancy;
4. Allergy to EIT electrodes;
5. Persistent hemodynamic instability or refractory shock;
6. Severe cardiopulmonary disease (e.g., severe COPD (Chronic obstructive pulmonary disease), NYHA (New York Heart Association) Class III or IV, acute coronary syndrome, or sustained ventricular tachycardia);
7. Severe pulmonary hypertension (systolic pulmonary artery pressure >40 mmHg);
8. Increased intracranial pressure, intracranial injury/tumor, or neuromuscular disorders;
9. Conversion to laparotomy;
10. Planned transfer to intensive care unit after surgery.