Effect of Low Tidal Volume Ventilation in Improving Oxygenation and Thus Reducing Acute Lung Injury in the Cardiac Surgical Patient

Study Overview
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Brief Summary
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We propose that as low tidal volume ventilation has proven to be beneficial in patients with established ARDS it may have a role in preventing the onset of acute lung injury in the cardiac surgical population. Institution of low tidal volume ventilation in the operating room may reduce the release of the cytokines and interleukins that have been known to contribute to the development of acute lung injury. In this study, we propose that the institution of low tidal volume ventilation in the operating room will reduce the incidence of acute lung injury. Measurement of PaO2 to FiO2 ratio twenty four and forty eight hours post operatively will help determine if there is a difference in oxygenation between the two groups. Chest X-ray findings, time to extubation and length of ICU stay will also determine if there is a role for low tidal volume ventilation in the operating room. We will also attempt to establish a causative mechanism by measuring plasma levels of cytokines known to be associated with the development of ARDS.

Detailed Description
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Methods- A single center randomized controlled trial was undertaken in 149 patients comparing ventilation with 6 ml/kg TV to ventilation with 10 ml/kg TV in patients undergoing elective cardiac surgery. Study ventilator settings were applied immediately after induction of anesthesia and continued throughout surgery and the subsequent Intensive Care Unit stay. The primary endpoint of the study was time to extubation. Secondary endpoints included the proportion of patients extubated at 6 hours, indices of lung mechanics and gas exchange as well as patient clinical outcomes.

Official Title
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Effect of Low Tidal Volume Ventilation in Improving Oxygenation and Thus Reducing Acute Lung Injury in the Cardiac Surgical Patient

Conditions
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Acute Respiratory Distress Syndrome

Intervention / Treatment
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* Other: Ventilation strategy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients coming in for cardiac surgical procedures will be recruited into the study. Both men and women will be recruited into the study. All patients over the age of 18 will be recruited into the study. Discussion between the surgeon and the primary investigator will happen prior to approaching the patient to obtain informed consent. Exclusion Criteria: Patients with preexisting respiratory failure and active infection will be excluded from the study. Patients undergoing one lung ventilation during surgery will be excluded from the study. Patients undergoing emergency cardiac surgery will be excluded from the study.

Ages Eligible for Study
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Minimum Age: 18 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: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Low tidal volume arm<br> | Other: Ventilation strategy<br> <br> |
| Active Comparator: Conventional tidal volume arm<br> | Other: Ventilation strategy<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Time to extubation |  | the time patient was extubated in the ICU | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Oxygenation at 4 hours, 8 hours, 12 hours and 24 hours post surgery. |  | measurement of blood gas at 4, 8 , 12 and 24 hours post surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Acute lung injury, cardiac surgery, The incidence of ARDS after elective cardiac surgery is 1-3%, The impairment of lung function and oxygenation may occur in 20-80% of patients undergoing surgery., The purpose of this study is to assess the efficacy of low tidal volume ventilation., Reducing interleukin and cytokine production may prevent or reduce the incidence of acute lung injury.