Protective Variable Ventilation for Open Abdominal Surgery

Study Overview
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Brief Summary
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Variable ventilation has been shown to improve lung function and reduce lung damage as well as inflammation in different models of the acute respiratory distress syndrome. Also, variable ventilation is able to recruit lungs. The present study will investigate whether variable as compared to non-variable ventilation improves post-operative lung function and reduces systemic inflammation in patients submitted to open abdominal surgery.

Official Title
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Effects of Variable Tidal Volumes During Open Abdominal Surgery on Lung Function and Systemic Inflammation

Conditions
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Development of Pulmonary Dysfunction Following Open Abdominal Surgery

Intervention / Treatment
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* Other: Variable Ventilation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: elective open abdominal surgery ASA classification 2-3 age between 18 und 85 yrs expected duration of surgery > 3 h expected extubation in the operation room written informed consent Exclusion Criteria: chronic lung disease (except to COPD stadium I and II, and asthma) Body Mass Index (BMI) > 40 allergy to one of the drugs to be used for general anesthesia participation in another interventional trial within 4 weeks before enrollment addiction or any other disease that may interfere with the capacity of giving informed consent pregnant or breastfeeding women women in reproductive age, except to those who fulfill one of the following: post-menopause (12 months natural amenorrhoea, or 6 months amenorrhoea and serum FSH > 40 mlU/ml post-operative (6 weeks after two-sided ovariectomy) routine and correct use of anticonceptional methods with failure rate < 1 % per year sexually not active vasectomy of the partner indication of low compliance with the protocol contraindication for MRI examination

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 85 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Variable Ventilation<br>Variable tidal volumes with mean at 8 mL/kg of predicted body weight | Other: Variable Ventilation<br> <br> |
| No Intervention: Non-variable Ventilation<br>Conventional mechanical ventilation with tidal volume 8 mL/kg of predicted body weight | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Forced vital capacity | Forced vital capacity is assessed on the first postoperative day | Preoperative until 5th postoperative day | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Arterial partial CO2 pressure | PacO2 on the first postoperative day | Preoperative until 5th postoperative day | 
| Peak expiratory flow |  | Preoperative until 5th postoperative day | 
| Forced expiratory volume after 1 sec | Forced expiratory volume after 1 sec (FEV1) on first postoperative day | Preoperative until 5th postoperative day | 
| PaO2/FIO2 | PaO2/FIO2 during the intraoperative period | Preoperative until 5th postoperative day | 
| Distribution of ventilation | Distribution of ventilation in lungs | Preoperative until 5th postoperative day | 
| Atelectasis | Amount of lung atelectasis on the first postoperative day | Preoperative until 5th postoperative day | 
| Postoperative pulmonary complications | Development of postoperative pulmonary complications | Preoperative until discharge from hospital | 
| Inflammation markers | Concentrations of interleukine(IL)-6, IL-8 and tumor necrosis factor(TNF)-alpha in plasma | Preoperative until 5th postoperative day | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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mechanical ventilation, lung function, abdominal surgery, open, systemic inflammation