Supplemental Oxygen in Pulmonary Embolism (SO-PE)

Early Phase 1

Recruiting

• Conditions: Pulmonary Embolism; Venous Thromboembolism; Metabolomics; Oxygen Inhalation Therapy
• Interventions: Drug: Oxygen Therapy; Device: Non-rebreather mask

• Registration Number: NCT05891886
• Lead Sponsor: Massachusetts General Hospital

Brief Summary

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

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.

Study Timeline

• Study First Submitted: 2023-05-04
• Study First Submitted QC: 2023-05-26
• Study First Posted: 2023-06-07
• Status Verified: 2023-10
• Study Start: 2023-10-01
• Last Update Submitted: 2023-10-17
• Last Update Posted: 2023-10-19
• Primary Completion: 2027-06-30
• Study Completion: 2027-06-30

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 80

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

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Supplemental oxygen delivered by facemask	Oxygen Therapy	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.
Room air delivered by facemask	Non-rebreather mask	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.
Supplemental oxygen delivered by facemask	Non-rebreather mask	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.

Primary Outcome Measures

Name	Time	Method
Pulmonary artery systolic pressure (PASP)	180 minutes after study treatment (supplemental oxygen) or placebo (room air)	PASP is measured on bedside echocardiogram

Secondary Outcome Measures

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

Trial Locations

Locations (1)

Massachusetts General Hospital; 🇺🇸 Boston, Massachusetts, United States