Effects of Individualized PEEP Guided by Driving Pressure on Postoperative Atelectasis in Patients With Morbid Obesity

NCT06181279 | Recruiting

• 1 other identifier: DP guided PEEP
• Study Type: interventional
• Target: 52
• Locations: 1 country
• Sites: 1

Brief Summary

Atelectasis is a common complication in patients undergoing surgery under general anesthesia, particularly in obese patients. Postoperative atelectasis could last for more than 24h and contribute to a variety of other complications, including hypoxemia and pneumonia. We plan to conduct a single-center, randomized controlled trial in patients undergoing bariatric surgery to test the hypothesis that driving pressure guided PEEP could reduce the postoperative atelectasis.

Conditions

Pulmonary Atelectasis; Obesity, Morbid

Keywords

Individual Positive End-expiratory Pressure; Driving Pressure; Ventilator-induced Lung Injury

Outcome Measures

Primary Outcomes (1)

• Incidence of postoperative pulmonary atelectasis

  The primary outcome of this study is postoperative atelectasis measured by lung ultrasound. Each hemithorax is divided into 6 regions using 3 longitudinal lines (parasternal, anterior and posterior axillary)and 2 axial lines (one above the diaphragm and the other 1 cm above the nipples). The 12 lung regions were scanned sequentially from right to left, cranial to caudal and anterior to posterior. Each region is assessed using a 2-dimen-sional view with the probe placed parallel to the ribs. It distinguishes four progressive steps of loss of aeration according to the artifacts visualized in a scan: score 0, normal aeration (A-lines or no more than two B-lines); score 1, moderate loss of aeration (three or more well-spaced B-lines); score 2, severe loss of aeration(coalescent B-lines); and score 3, complete loss of aeration(tissue-like pattern). We define atelectasis to be significant if any region had a lung consolidation score of ≥2.

  After 30 minutes of extubation

Secondary Outcomes (1)

• Postoperative pulmonary ultrasound score

  After 30 minutes of extubation

Study Arms (2)

Individualized PEEP group

EXPERIMENTAL

After recruitment maneuver, PEEP is titrated decreasingly using driving pressure guided individualised PEEP ventilation strategy, and the PEEP corresponding to the lowest driving pressure is the individualised PEEP.

Procedure: Individualized PEEP group

Fixed PEEP group

OTHER

After recruitment maneuver, PEEP is fixed at 8cmH2O.

Procedure: Fixed PEEP group

Interventions

Individualized PEEP group PROCEDURE

Individualized PEEP group: Recruitment Maneuver (RM) is performed first. In pressure control mode, PEEP and airway plateau pressure are increased to 20 cmH2O and 35 cmH2O at a rate of 5 cmH2O every 30s, and driving pressure is maintained at 15 cmH2O throughout. Subsequently, in volume-controlled ventilation mode, PEEP decreases from 20 cmH2O to 4 cmH2O at gradient of 2 cmH2O, and each PEEP level is maintained for 30s. The PEEP corresponding to the lowest driving pressure is the individualized PEEP we need. If multiple PEEP levels showed the same lowest driving pressure, the lowest PEEP value as the individualized PEEP. The above procedures are performed three times during the surgery (5 minutes after intubation,5 minutes after the beginning of pneumoperitoneum, and 5 minutes after the end of pneumoperitoneum).

Individualized PEEP group

Fixed PEEP group PROCEDURE

After the same RM, PEEP is fixed at 8 cmH2O.

Fixed PEEP group

Eligibility Criteria

• Age: 18 Years - 60 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64)

You may qualify if:

• Age 18 to 60 years old;
• Body mass index (BMI) ≥ 40 kg/m2;
• ASA classification I to III;
• Signing the informed consent form for this clinical study;

You may not qualify if:

• Respiratory infection within 4 weeks; severe respiratory system diseases; history of pulmonary and/or thoracic surgery; neuromuscular dysfunction;
• Serious cardiac, renal or haematopoietic diseases;
• Contraindications to PEEP；

Sponsors & Collaborators

• Yongtao Sun: lead

Study Sites (1)

Qianfoshan Hospital, The First Hospital affiliated of Shandong First Medical University

Jinan, Shandong, 250014, China

RECRUITING

Related Publications (1)

• Ren Y, Sun YT, Zhang P, Chen L, Liu P, Zhou Z, Wang Y. Effect of driving pressure-guided individualised positive end-expiratory pressure on postoperative atelectasis in patients with morbid obesity: study protocol of a randomised controlled trial. BMJ Open. 2025 Mar 6;15(3):e091217. doi: 10.1136/bmjopen-2024-091217.

  PMID: 40050061 DERIVED

MeSH Terms

Conditions

Pulmonary Atelectasis; Obesity, Morbid; Ventilator-Induced Lung Injury

Condition Hierarchy (Ancestors)

Lung Diseases; Respiratory Tract Diseases; Obesity; Overweight; Overnutrition; Nutrition Disorders; Nutritional and Metabolic Diseases; Body Weight; Signs and Symptoms; Pathological Conditions, Signs and Symptoms; Lung Injury

Study Officials

• yong t Sun, Ph.D

  Shandong First Medical University

  STUDY CHAIR

Central Study Contacts

yong t Sun, Ph.D

CONTACT

18660795201; sunyongtao1979@163.com

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR INVESTIGATOR
• PI Title: professor

Study Record Dates

• First Submitted: December 12, 2023
• First Posted: December 26, 2023
• Study Start: March 1, 2024
• Primary Completion: December 31, 2024
• Study Completion: December 31, 2024
• Last Updated: June 4, 2024

Record last verified: 2024-06

Locations

CN (1)