EIT-guided PEEP Titration Versus Standard Ventilation in Bariatric Surgery

Prevention of Postoperative Pulmonary Complications in Patients Undergoing Laparoscopic Gastric Sleeve Resection by PEEP Titration Based on EIT: A Randomized Controlled Study

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.

This is a single-center, single-blind，randomized controlled trial conducted at the First Affiliated Hospital of Shandong First Medical University in Jinan City,Shandong Province, China. This randomized controlled trial has been approved by the Ethics Committee of The First Affiliated Hospital of Shandong First Medical University (YXLL-KY-2025(107)).And it complies with the Standard Protocol Items: Recommendations for Interventional Trials (SPIRIT) guidelines. A total of 118 participants will be randomly allocated to the EIT-guided individualized PEEP group (Group P ) (n = 59) or the control group (Group C) (n = 59). Recruitment for this study has begun on July 28, 2025, and will continue through the end of 2026.

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.