Forced Oscillation Technique (FOT) and Expiratory Flow Limitation (EFL)

Diagnosing Expiratory Flow Limitation in COPD Patients With the Forced Oscillation Technique Using Linear Regression in the Time Frequency Domain

Status

Completed

Phases

Unknown

Study type

Observational

Source

ClinicalTrials.gov

Registry ID

NCT00499304

Enrollment

Registered

2007-07-11

Start date

2006-11-30

Completion date

2008-04-30

Last updated

2008-06-06

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

COPD

Keywords

Forced oscillation Technique (FOT), Expiratory flow limitation (EFL), Breathing artifacts, COPD

Brief summary

The aim of this study is to distinguish COPD patients with expiratory flow limitation in body plethysmography (open loop) from the patients without expiratory flow limitation in body plethysmography (closed loop) with the obtained FOT parameters.

Detailed description

In daily practice the expiratory flow limitation is measured by body plethysmography. An open loop in body plethysmography shows expiratory flow limitation in COPD patients. But body plethysmography requires that the patient quietly sits in a closed box and is not able to follow changes breath by breath. The goal of this study is to validate the Forced oscillation technique (FOT) for measuring expiratory flow limitation in COPD patients.30 COPD patients with an open loop in body plethysmography are compared to 30 COPD patients with a closed loop. The methods used in this study are the maximal overlap discrete short time Fourier transform (MODFT) combined with a total least squares analysis. It is hypothesized that the obtained FOT parameters are able to distinguish the patients with expiratory flow limitation in body plethysmography from the patients without expiratory flow limitation in body plethysmography.Secondary study questions are: 1) to what extend are the FOT parameters distorted by breathing artifacts and measurement noise. 2)What changes can be detected by FOT in expiratory flow limitation after administration of salbutamol.

Interventions

None listed

Study design

Observational model

CASE_CONTROL

Time perspective

PROSPECTIVE

Eligibility

Sex/Gender

ALL

Age

50 Years to 80 Years

Healthy volunteers

Yes

Inclusion criteria

* Presenting to the outpatient clinic * Age 50-80 years * Diagnosed with COPD according to the standard criteria * Gold Stage II to IV COPD * Current or ex-smokers (at least 10 PY) * Stable disease (No current exacerbation or exacerbation during the 4 weeks previous to the inclusion)

Exclusion criteria

* History of exacerbation of COPD in the preceding month * Upper airway obstruction * Allergic Asthma * OSAS (obstructive sleep apnea syndrome) * Extreme obesity (BMI\>35) * Clinically manifest cardiac disease (for example clinically relevant congestive heart failure, unstable angina pectoris)

Countries

Netherlands

Outcome results