Supplemental Oxygen in Pulmonary Embolism (SO-PE)

Study Overview
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Brief Summary
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A study of how supplemental oxygen helps patients with acute pulmonary embolism (PE). Hypothesis: Oxygen affects right ventricular dysfunction (RVD) in patients with acute pulmonary embolism (PE) primarily by relieving hypoxic pulmonary vasoconstriction and reducing pulmonary pressure (PA) pressure, and that this process is metabolically driven.

Detailed Description
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In the Emergency Department (ED), investigators will perform a randomized, crossover trial of adult patients with acute PE. Study subjects will be randomized to one of two interventions (supplemental oxygen delivered by facemask) vs. room air. Therapy will be alternated at t=30, t=60, t=90 minutes, and then maintained for 180 minutes. After each treatment change, and at 180 minutes, investigators will: 1) perform echocardiograms to determine how oxygen affects right ventricular dysfunction (RVD) and, 2) draw blood for metabolomic analyses to determine the metabolic pathways that change in response to oxygen therapy.

Official Title
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Supplemental Oxygen in Pulmonary Embolism (SO-PE)

Conditions
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Metabolomics, Pulmonary Embolism, Venous Thromboembolism, Oxygen Inhalation Therapy

Intervention / Treatment
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* Drug: Oxygen Therapy
* Device: Non-rebreather mask


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adults ≥18 years old Confirmed Pulmonary Embolism (PE) on computed tomography pulmonary angiography (CTPA) performed <24 hours prior to enrollment Symptom duration <72 hours Confirmation of right ventricular dysfunction (RVD) by clinician Oxygen saturation ≥90% while breathing room air Exclusion Criteria: Hemodynamic instability Use of vasopressors or mechanical circulatory support Planned use of thrombolytics or plan for embolectomy Oxygen saturation <90% while breathing room air at any time in the Emergency Department (ED) New onset arrhythmia History of pulmonary hypertension, chronic obstructive pulmonary disease (COPD), hypoventilation syndrome, or congestive heart failure (CHF) with left ventricular ejection fraction <40% Known pregnancy Use of chronic oxygen therapy at baseline Vasodilator medication used in the past 24 hours Symptom onset ≥72 hours Inability to wear a face mask Technically inadequate baseline echocardiogram Temperature >39° C Positive test for Covid-19 or influenza within the previous 10 days

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: Other
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Supplemental oxygen delivered by facemask<br>Patients with acute PE will be randomized to breathing supplemental oxygen by non-rebreather face mask first. Subjects will alternate treatments (supplemental oxygen or room air) every 30 minutes for 90 minutes (e.g. T=30, T=60, T=90) and then will maintain their treatment (oxygen or room air) for a total of 180 minutes. | Drug: Oxygen Therapy<br>* Study subjects will be asked to breathe supplemental, or extra, oxygen during several time periods.<br>Device: Non-rebreather mask<br>* Non-rebreather mask is a non-invasive oxygen supplementation device that is used to provide continuous oxygen flow, typically in a hospital setting.<br>* Other names: NRM (Non-rebreather mask);|
| Active Comparator: Room air delivered by facemask<br>Patients with acute PE will be randomized to breathing room air by non-rebreather face mask first. Subjects will alternate treatments (supplemental oxygen or room air) every 30 minutes for 90 minutes (e.g. T=30, T=60, T=90) and then will maintain their treatment (oxygen or room air) for a total of 180 minutes. | Device: Non-rebreather mask<br>* Non-rebreather mask is a non-invasive oxygen supplementation device that is used to provide continuous oxygen flow, typically in a hospital setting.<br>* Other names: NRM (Non-rebreather mask);|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Pulmonary artery systolic pressure (PASP) | PASP is measured on bedside echocardiogram | 30 minutes after study treatment (supplemental oxygen) or placebo (room air) | 
| Pulmonary artery systolic pressure (PASP) | PASP is measured on bedside echocardiogram | 60 minutes after study treatment (supplemental oxygen) or placebo (room air) | 
| Pulmonary artery systolic pressure (PASP) | PASP is measured on bedside echocardiogram | 90 minutes after study treatment (supplemental oxygen) or placebo (room air) | 
| Pulmonary artery systolic pressure (PASP) | PASP is measured on bedside echocardiogram | 180 minutes after study treatment (supplemental oxygen) or placebo (room air) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Right ventricular to left ventricular ratio (RV/LV) | RV/LV ratio is measured on bedside echocardiogram | 30 minutes after study treatment (supplemental oxygen) or placebo (room air) | 
| Right ventricular to left ventricular ratio (RV/LV) | RV/LV ratio is measured on bedside echocardiogram | 60 minutes after study treatment (supplemental oxygen) or placebo (room air) | 
| Right ventricular to left ventricular ratio (RV/LV) | RV/LV ratio is measured on bedside echocardiogram | 90 minutes after study treatment (supplemental oxygen) or placebo (room air) | 
| Right ventricular to left ventricular ratio (RV/LV) | RV/LV ratio is measured on bedside echocardiogram | 180 minutes after study treatment (supplemental oxygen) or placebo (room air) | 
| Concentrations of circulating metabolites and metabolic profiles measured by high-throughput metabolomic assays | Investigators will perform high-throughput metabolomics to identify changes in circulating blood metabolites associated with supplemental oxygen use in patients with acute PE. | 30 minutes after study treatment (supplemental oxygen) or placebo (room air) | 
| Concentrations of circulating metabolites and metabolic profiles measured by high-throughput metabolomic assays | Investigators will perform high-throughput metabolomics to identify changes in circulating blood metabolites associated with supplemental oxygen use in patients with acute PE. | 60 minutes after study treatment (supplemental oxygen) or placebo (room air) | 
| Concentrations of circulating metabolites and metabolic profiles measured by high-throughput metabolomic assays | Investigators will perform high-throughput metabolomics to identify changes in circulating blood metabolites associated with supplemental oxygen use in patients with acute PE. | 90 minutes after study treatment (supplemental oxygen) or placebo (room air) | 
| Concentrations of circulating metabolites and metabolic profiles measured by high-throughput metabolomic assays | Investigators will perform high-throughput metabolomics to identify changes in circulating blood metabolites associated with supplemental oxygen use in patients with acute PE. | 180 minutes after study treatment (supplemental oxygen) or placebo (room air) | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Pulmonary Embolism, PE, RVD