Transpulmonary Pressure Guided Mechanical Ventilation Weaning in Obesity

Study Overview
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Brief Summary
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This study will look at whether accounting for the amount of pressure generated by the chest wall and abdomen in a obese patient, using a measurement called transpulmonary pressure, can help shorten the amount of time patients spend on the ventilator. By decreasing the amount of time patients spend on the ventilator, they are less likely to develop complications such as infections, weakness or more procedures.

Detailed Description
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Managing obese patients on the ventilator can be difficult due to the changes in their respiratory mechanics with little evidence as to best practices. This research will assess the utility of transpulmonary pressures in guiding mechanical ventilation in obese patients. This study with specifically look at whether using transpulmonary pressure guided positive end expiratory pressure (PEEP) titration for ventilation and spontaneous breathing trials (SBT) will shorten the time to liberation for obese patients on invasive mechanical ventilation for respiratory failure. The transpulmonary pressures will be calculated daily for all patients. Patients will also be assessed daily for readiness for SBT. In the intervention group, subjects' PEEP will be titrated to achieve an end expiratory transpulmonary pressure of 0-2 cm H2O. This PEEP will be used for the SBT and clinicians will be encouraged to keep their patients on this PEEP after the SBT if they are not extubated. In the control group, patients will also be assessed daily for SBT readiness but will be managed with standard set pressures of 5 to 10 cm H2O of PEEP and 5 to 8 cm H2O of pressure above PEEP. The primary team can perform a T piece trial prior to extubation as clinically indicated.

Official Title
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Transpulmonary Pressure Guided Weaning From Invasive Mechanical Ventilation in Obese Patients With Respiratory Failure

Conditions
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Respiratory Failure, Obesity

Intervention / Treatment
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* Other: transpulmonary pressure guided positive end expiratory pressure
* Other: standard positive end expiratory pressure


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: on invasive mechanical ventilation for respiratory failure for < 48 hours obese class II or higher (BMI greater than or equal to 35.0 kg/m2) Exclusion Criteria: contraindications to esophageal balloon catheter placement including esophageal, nasofacial, gastrointestinal abnormalities and platelets <10,000/microliter known pleural disease such as persistent pneumothorax, pleural effusion, or pleurodesis neuromuscular disease requires chronic mechanical ventilation prior to enrollment severe neurologic injury known difficult airway life expectance is less than 48 hours

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: Supportive Care
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Transpulmonary pressure guided positive end expiratory pressure<br>Patients in this group will have the positive end expiratory pressure on the ventilator set to a transpulmonary pressure of 0-2 cm H2O during ventilation and spontaneous breathing trials. | Other: transpulmonary pressure guided positive end expiratory pressure<br>* Positive end expiratory pressure will be titrated to achieve a transpulmonary pressure of 0-2 cm H2O<br>|
| Active Comparator: Standard positive end expiratory pressure<br>Patients in this groups will have the positive end expiratory pressure on the ventilator set by the clinician during ventilation and set to a standard positive end expiratory pressure of 5-8 cm H2O during spontaneous breathing trials. | Other: standard positive end expiratory pressure<br>* Positive end expiratory pressure will be set to a standard 5-8 cm H2O by the clinician for spontaneous breathing trials<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Ventilator free days | Number of ventilator free days | 30 days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Mortality | Number of patients who died during the study | 30 days | 
| Days on invasive mechanical ventilation | Number of days patient spent on mechanical ventilation | 30 days | 
| Re-intubation rate | Percentage of patients who were re-intubated after extubation failure | 30 days | 
| Number of tracheostomies | Number of patients who received tracheostomies | 30 days | 
| PEEP at extubation | the amount of positive end expiratory pressure set on the ventilator prior to extubation | 30 days | 
| Intensive care unit length of stay | Number of days spent in the intensive care unit | 30 days | 
| Hospital length of stay | Number of days spent in the hospital | 30 days | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Transpulmonary pressure, Respiratory failure, Obesity, Invasive mechanical ventilation