AzTrials
AzTrials

Pulmonary EmbolismPhase 2/3NCT00368836

Breath Analysis Technique to Diagnose Pulmonary Embolism

A Phase 2/3 study testing BreathScreen PE in people with Pulmonary Embolism, run by Wake Forest University Health Sciences at 1 site in United States.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record
Search all trials

Trial summary

A pulmonary embolism (PE) is a blockage in one of the arteries of the lungs, and is usually caused by a traveling blood clot. The D-dimer blood test is currently used to diagnose PEs, but it is not always accurate for individuals who have recently undergone surgery or who have inflammatory-provoking diseases. Read more about this study

Who is it for?
Ages 18 years and older
Conditions the study is for
Pulmonary Embolism
What is being tested?
BreathScreen PE
Type of treatment
Medical device
Could I receive a placebo?
No, everyone receives an active treatment
How many people
475 participants
Where
1 siteUnited States
Study dates
Jan 2006to Jun 2008
Phase
Phase 2/3
Are there results?
Yes, posted in the registrySummary in the doctors' view

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 18 years and older
  • All sexes
  • No healthy volunteers
  • Adult, Older adult

Phase I Inclusion Criteria:

  • Experienced or is scheduled for at least one of the following:
  1. Hip or knee replacement surgery
  2. Hip or acetabular fracture surgery
  3. Pelvic fracture
  4. Decompression for spinal stenosis surgery
  5. Scoliosis corrective surgery
  6. Craniotomy surgery for brain tumor
  7. Surgery for any of the following cancers: bladder, colon (including caecum and rectum), kidney, ovary, pancreas, or uterus

Phase I Exclusion Criteria:

  • Currently undergoing treatment for PE or has received treatment for PE in the 4 weeks prior to study entry
  • Hospitalized for fewer than 2 days
  • Anatomic abnormality that would prevent use of a mouthpiece
  • Living situation that makes follow-up difficult (e.g., homeless, incarcerated)

Phase II Inclusion Criteria:

  • Clinical suspicion of PE with signs or symptom suggestive of PE within 24 hours of presentation and at least one risk factor for PE, as defined under the criteria as outlined in this protocol
  • CTA of pulmonary arteries ordered by clinical care providers
  • 18 years or older or an emancipated 17 year old
  • Written informed consent

Phase II Exclusion Criteria:

  • Hemodynamic instability, including patients with a systolic blood pressure less than 90 mm Hg
  • Severe respiratory distress or the inability to breathe room air without the sensation of severe dyspnea
  • Pulse oximetry reading that declines more than 10% when exogenous oxygen is discontinued with accompanying worsening or new dyspnea
  • Intubated
  • Cannot breathe through the mouth owing to anatomic, physical or mental limitation
  • No fixed address, no telephone number, are from out of town or have other reason to suspect difficulty with follow-up
  • Incarceration
  • Known active tuberculosis
  • Prior PE or DVT with history of medical noncompliance with oral anticoagulation therapy based upon a history of unplanned subtherapeutic INR measurements (less than 1.5)
  • Active PE within previous 6 months and currently under treatment with anticoagulation
  • Pregnant
  • Disallowed medications: treatment with any fibrinolytic agent within 48 hours prior to enrollment

Trial locations and contacts

1 site in 1 country.

United States1 site

  • Carolinas Medical Center

    Charlotte, North Carolina, 28203

Other trials in United States

About this study

Official title: Expired CO2/O2 Analysis to Diagnose Pulmonary Embolism

A pulmonary embolism (PE) is a blockage in one of the arteries of the lungs, and is usually caused by a traveling blood clot. The D-dimer blood test is currently used to diagnose PEs, but it is not always accurate for individuals who have recently undergone surgery or who have inflammatory-provoking diseases. The purpose of this study is to evaluate the effectiveness of the Carboximeter, a new PE diagnostic device that measures carbon dioxide (CO2) and oxygen (O2) output, in individuals at risk for developing PEs.

Read the detailed description

PE is the second leading cause of sudden, unexpected death in the United States. In 90% of the cases, it is caused by deep vein thrombosis: a blood clot forms in a vein, travels through the bloodstream, and lodges in the lungs. PE symptoms vary, and can include cough, shortness of breath, chest pain, rapid breathing, or increased heart rate. Some medical procedures and diseases activate inflammation and blood coagulation, thereby making individuals more vulnerable to PE. Surgery, kidney dialysis, cancer, connective tissue diseases, infectious diseases, and being over 70 years old put individuals at increased risk for developing PEs. A common screening test for PE is the D-dimer blood test, which measures the level of a specific protein that is released following a PE. This test, however, has proven to be an unreliable diagnostic tool for individuals who are at high risk for PE. A more reliable diagnostic tool is needed. The Carboximeter is a new device that measures the ratio of CO2/O2 pressure in an individual's expired breath. By monitoring these components, researchers may be able to accurately diagnose PEs in high risk individuals. The purpose of this study is to evaluate the effectiveness of the Carboximeter at diagnosing PE in individuals at risk for developing PEs.

This study will be conducted in two phases. In Phase I, CO2/O2 ratio and D-dimer levels will be measured prior to and following orthopedic or cancer-related surgery in 100 individuals at risk for developing PEs. In Phase II, the same measurements will be carried out on 350 high risk individuals who are experiencing PE symptoms. These individuals will also undergo computed tomography (CT) angiography and venography, in which blood flow will be visualized using x-rays. A follow-up evaluation will occur 30 days later. If any participant from Phase I or II experiences a PE or a medical condition that affects their lungs, such as asthma or chronic obstructive pulmonary disease (COPD), researchers may schedule a follow-up evaluation to obtain repeat measurements.

Being tested
BreathScreen PE
Keywords
Capnography, Thromboembolism, Arthroplasty, D-dimer
Medical subject headings
Pulmonary Embolism, Thromboembolism

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • BreathScreen PEDevice

    One minute of breath collection by tidal breathing into the BreathScreen PE and blood draw for D-dimer level

Study groups in NCT00368836
Study groupRoleWhat they receive
BreathScreen PE + D-dimerExperimentalCO2/O2 ratio will be measured using the Breath Screen PE device. D-dimer levels will also be collected.
Receives: Device: BreathScreen PE

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Phase I: Percentage Change in the Postoperative End Tidal CO2/O2 Ratio and D-dimer Concentration Relative to the Preoperative Measurement

    Median postoperative change in end tidal CO2/O2 ratio calculated as 100% * [(postoperative-preoperative)/(preoperative)]

    Measured: Pre-op measurement: the morning of surgery. Post-op measurement: the latter of postoperative day 3 or hospital discharge

  2. Phase II: Probability of Pulmonary Embolism Diagnosis by D-dimer Alone vs. D-Dimer Plus CO2/O2 for Pulmonary Embolism Diagnosed by CT Scan.

    D-dimer > 499 ng/ml, etCO2/O2 < 0.28, Pulmonary Embolism diagnosed by CT scan

    Measured: Measured at 45 days

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted29 Aug 2006 (estimated)
  2. Study startJan 2006
  3. Primary completionApr 2008
  4. Study completionJun 2008

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Interventional
Phase
Phase 2/3
Primary purpose
Other
Allocation
Not applicable
Intervention model
Single group
Masking
None (open label)
Enrolment
475 participants (actual)
IDs, dates and publications
ClinicalTrials.gov ID
NCT00368836
Sponsor's protocol ID
433
Other IDs
R42HL086316-01
Status last verified
Jun 2021
First submitted
24 Aug 2006
Last updated
21 Apr 2022
Data monitoring committee
Yes

Publications

  • Kline JA, Hogg M. Measurement of expired carbon dioxide, oxygen and volume in conjunction with pretest probability estimation as a method to diagnose and exclude pulmonary venous thromboembolism. Clin Physiol Funct Imaging. 2006 Jul;26(4):212-9. doi: 10.1111/j.1475-097X.2006.00672.x.

    PubMed 16836693

  • Kline JA, Watts J, Courtney D, Lee YY, Hwang S. Severe pulmonary embolism decreases plasma L-arginine. Eur Respir J. 2014 Mar;43(3):906-9. doi: 10.1183/09031936.00171913. Epub 2013 Nov 14. No abstract available.

    PubMed 24232703

  • Kline JA, Hogg MM, Courtney DM, Miller CD, Jones AE, Smithline HA. D-dimer threshold increase with pretest probability unlikely for pulmonary embolism to decrease unnecessary computerized tomographic pulmonary angiography. J Thromb Haemost. 2012 Apr;10(4):572-81. doi: 10.1111/j.1538-7836.2012.04647.x.

    PubMed 22284935

  • Kline JA, Hogg MM, Courtney DM, Miller CD, Jones AE, Smithline HA, Klekowski N, Lanier R. D-dimer and exhaled CO2/O2 to detect segmental pulmonary embolism in moderate-risk patients. Am J Respir Crit Care Med. 2010 Sep 1;182(5):669-75. doi: 10.1164/rccm.201001-0129OC. Epub 2010 May 6.

    PubMed 20448094

Questions about this trial

What is this clinical trial studying?

A Phase 2/3 study testing BreathScreen PE in people with Pulmonary Embolism, run by Wake Forest University Health Sciences at 1 site in United States.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: finished, as of the sponsor's last update on 21 Apr 2022. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

What does this combined phase mean?

Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.

Phase 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.

Not every study follows the same path, and some studies (observational studies, device studies) have no phase.

Are results available for this study?

Yes. Results are posted in the registry (first posted 30 Jun 2021). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Phase I: Percentage Change in the Postoperative End Tidal CO2/O2 Ratio and D-dimer Concentration Relative to the Preoperative Measurement (time frame: Pre-op measurement: the morning of surgery. Post-op measurement: the latter of postoperative day 3 or hospital discharge). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT00368836, which also lists 4 linked publications.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 21 Apr 2022.

AzTrials uses cookies for analytics and advertising. You can accept or reject them; the site works either way. Privacy Policy.

Free account

Log in to keep searching

You’ve used your 3 free searches. AzTrials is free: log in or create a free account to keep searching clinical trials and save the ones you want to follow.

Create a free accountLog in