An Association Between Asthma Severity and Capnography Parameters

Asthma is a common chronic disorder of the airways characterized by periods of reversible airflow obstruction known as asthma episodes or attacks. Asthma attacks are caused by chronically hyperactive (contraction of the muscles surrounding the airways) and inflamed airways, leading to airflow obstruction, and may be mild, moderate, or severe enough to become life-threatening events. Severity of asthma exacerbation is assessed through medical history and lung function measurements with Spirometer and requires full cooperation of the patient. Thus, in uncooperative populations or during emergency medical situations the spirometer cannot be used. As an alternative, capnography data has been proposed as an indicator of bronchospasm in asthma. Previous studies found correlations between the capnography parameters and methacholine challenge in asthma patients. However, the relationship between capnography parameters and severity of asthma or severity of asthma exacerbation have not been well characterized. The study hypothesis is that within the clinical population that is invited to do the methacholine challenge, a different waveform pattern in asthma patients will be detected and possibly a correlation between the severity of obstruction and pattern of waveform during the methacholine challenge. In this proposed feasibility observational study, sixty subjects, both men and women, who will be invited to participate in the methacholine challenge in the Institute of Pulmonary Medicine at Rabin Medical Center, will be recruited to the study. Respiratory information will be recorded using the CapnostreamTM20p while the subjects will wear the non-invasive Smart CapnoLine® Plus sampling line. Additionally, FeNO will be measured using a DENOX 88 device during the methacholine challenge.

Study Overview

• Status: Completed
• Conditions: Asthma
• Intervention / Treatment: Device: Capnostream20p

• Study Type: Observational
• Enrollment (Actual): 73

Contacts and Locations

Study Locations

• Israel
  • Petach Tikva, Israel, 49100
    • Pulmonary Institute Rabin Medical center, Beilinson Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 70 years (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

Sixty subjects, both men and women, who will be invited to participate in the methacholine challenge in the Institute of Pulmonary Medicine at Rabin Medical Center, regardless to the study, will be recruitment to the study.

Description

Inclusion Criteria:

1. The subject was invited to participate in methacholine challenge for the purposes of clinical assessment, with no relation to this study
2. Age 18-70
3. Ability to sign informed consent form

Exclusion Criteria:

1. Cannot or not willing to have capnography measurement during the entire methacholine challenge
2. Has or had in the past chronic obstructive pulmonary disease (COPD)

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Healthy volunteers	Device: Capnostream20p; The device will be used to monitor respiratory co2 values during the methacholine challenge, a well known diagnostic procedure
Asthma patients	Device: Capnostream20p; The device will be used to monitor respiratory co2 values during the methacholine challenge, a well known diagnostic procedure

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Measuring the change in expired CO2 over time in asthma patients during the methacholine challenge.	1 year

Secondary Outcome Measures

Outcome Measure	Time Frame
Finding a correlation between the change in expired CO2 and the severity of asthma as reflected by PC20.	1 year
Finding a correlation between the change in expired CO2 and the severity of asthma as reflected by the frequency of symptoms according the Asthma Severity Tool (AST).	1 year
Finding correlations between changes in capnography parameters and the severity of asthma as reflected by preliminary FEV1, forced vital capacity (FVC), FEV1/FVC, and peak expiratory flow rate.	1 year
Finding a correlation between change in expired CO2 and fraction of exhaled nitric oxide (FeNO).	1 year

Collaborators and Investigators

• Sponsor: Oridion

Study record dates

Study Major Dates

• Study Start: December 1, 2014
• Primary Completion (Actual): June 1, 2015
• Study Completion (Actual): June 1, 2015

Study Registration Dates

• First Submitted: November 4, 2014
• First Submitted That Met QC Criteria: November 17, 2014
• First Posted (Estimate): November 20, 2014

Study Record Updates

• Last Update Posted (Estimate): November 2, 2016
• Last Update Submitted That Met QC Criteria: November 1, 2016
• Last Verified: November 1, 2016

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Respiratory Tract Diseases; Immune System Diseases; Lung Diseases; Hypersensitivity, Immediate; Bronchial Diseases; Lung Diseases, Obstructive; Respiratory Hypersensitivity; Hypersensitivity; Asthma
• Other Study ID Numbers: D007773