Effect of Intraoperative Dynamic Compliance Guided Individualized Positive End-expiratory Pressure on Postoperative Atelectasis After Laparoscopic Bariatric Surgery

Xuzhou Medical University40 enrolled

Overview

This study intends to explore the effect of dynamic compliance guided individualized positive end-expiratory pressure titration strategy on reducing the level of postoperative atelectasis in obese patient who have laparoscopic bariatric surgery.The results of the study are to assess the effects of this intervention on the incidence，duration of postoperative atelectasis and other complications including hypoxemia etc. after laparoscopic bariatric surgery.And reducing the burden of postoperative atelectasis on patients and their families, hospitals and public resources.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

TRIPLE

Enrollment

Conditions

Postoperative Atelectasis

Interventions

Dynamic compliance guided individualized positive end-expiratory pressure titration strategy

Basic ventilation: Volume-controlled ventilation (VCV) mode with positive end-expiratory pressure (PEEP) of 8cm H2O after induction of anesthesia， Recruitment maneuver (RM): Pressure-controlled ventilation (PCV) mode increasing PEEP from 10 to 25cmH2O in step of 5cmH2O per 30s. PEEP-titration maneuver: ventilation parameters reset as basic ventilation with PEEP still 25cmH2O.Decrease PEEP to 5cmH2O in step of 2cmH2O per 10 respiratory cycles to confirm the highest dynamic lung compliance (Cdy). After titration: A new RM will be performed and the final PEEP will be the one related to highest Cdy plus 2cm H2O. Randomized after the second RM. Individualized PEEP arm: maintain individualized PEEP; PEEP8 arm: maintain a fixed PEEP of 8cm H2O. VCV with other ventilation parameters the same as basic ventilation until extubation . After discharged from postoperative anesthesia care unit (60 to 90 minutes after extubation): chest CT .

Eligibility

Sex: ALLMin age: 18 Years

Medical Language ↔ Plain English

Inclusion Criteria: 1. Bmi ≥ 35 kg/ m2 2. over 18 years old 3. elective laparoscopic bariatric surgery (gastric bypass or sleeve) Exclusion Criteria: 1. ASA \>IV 2. Lung bullae 3. thoracic surgery history 4. quit smoking less than 1 week 5. chronic obstructive pulmonary disease requiring oxygen 6. congestive heart failure (New York Heart Association classification ≥ III) 7. planned to be transferred to intensive care unit after surgery 8. Patients participating in another interventional study 9. Refuse to sign the informed consent

Locations (1)

Department of Anesthesia of the Affiliated Hospital of Xuzhou Medical University

Xuzhou, Jiangsu, China

Outcomes

Primary Outcomes

Percentage of postoperative atelectasis

The amount of postoperative atelectasis, expressed as the percentage of lung tissue in CT.

Time frame: 60-90 minutes after extubation

Secondary Outcomes

pulse oxygen

Continuous measurement of 24h pulse oxygen after surgery（%）

Time frame: 24 hours after surgery

PaO2/FiO2 ratio

Time frame: 1 day before surgery(baseline)，5 minutes after anesthesia induction，1 hour after pneumoperitoneum，before extubation，30 minutes after extubation

Quality of Recovery Score - 40 (QoR-40)

Quality of recovery will be evaluated by Quality of Recovery 40 (QoR40),which assesses five dimensions of recovery (physical comfort,emotional state, physical independence , physiological support and pain ). Each item is rated on a five-point Likert scale: none of the time, some of the time, usually, most of the time, and all the time. The total score on the QoR40 ranges from 40 (poorest quality of recovery) to 200 (best quality of recovery).

Time frame: 1 day before surgery(baseline)，1，2，7，30 days after surgery

Mini-Mental score examination (MMSE)

Mini-Mental score examination \[MMSE\] used for screening of dementia.The total score on the MMSE ranges from 0 (most severe dementia) to 24 (no dementia).

Time frame: 1 day before surgery(baseline)，1，2 days after surgery

Postoperative Complication

including pulmonary and other systematic postoperative complications

Time frame: 1，2，7 days after surgery

Mean arterial pressure

Mean arterial pressure = (systolic blood pressure + 2 × diastolic blood pressure) / 3（mmHg）