Related Experiment Video
Updated: Aug 14, 2026
13:28
Methodology for Sputum Induction and Laboratory Processing
Published on: December 17, 2017
Nitrogen washout slope in poorly controlled asthma
A Bourdin1, F Paganin, C Préfaut
1Service des Maladies Respiratoires, Hôpital Arnaud de Villeneuve, CHU de Montpellier, Montpellier, France.
Allergy
|December 21, 2005
Summary
The single breath nitrogen washout test effectively identifies small airway dysfunction in asthma, even with normal lung function tests. This method can predict poor asthma control and frequent exacerbations, guiding new treatment strategies.
Area of Science:
- Pulmonary Medicine
- Respiratory Physiology
Background:
- Asthma control is often inadequate despite normal spirometry, suggesting small airway involvement.
- Assessing small airways noninvasively is challenging, but the single breath nitrogen washout test (SBNT) shows promise.
Purpose of the Study:
- To evaluate the utility of SBNT in assessing small airway ventilation inequalities in asthma patients.
- To correlate SBNT parameters with asthma control, exacerbation rates, and other lung function measures.
Main Methods:
- Twenty-four asthma patients and 24 healthy controls underwent SBNT after bronchodilation.
- Measurements included spirometry, plethysmography, and SBNT phase III (dN2) and phase IV (closing capacity).
- Asthma control and exacerbation history were assessed using validated questionnaires and guidelines.
Main Results:
- Asthma patients showed increased closing capacity/total lung capacity (CC/TLC) and slope of phase III (dN2) compared to controls.
- dN2 was significantly higher in asthmatics with frequent exacerbations.
- dN2 correlated significantly with asthma control, exacerbation frequency, and residual volume/total lung capacity (RV/TLC).
Conclusions:
- Ventilation inequalities measured by dN2 using SBNT are a key indicator of poor asthma control and frequent exacerbations.
- SBNT is a valuable tool for assessing small airway dysfunction in asthma.
- Findings support the development of novel therapies targeting small airways in asthma management.
Related Concept Videos
01:30Asthma-IV: Nursing Management
The nursing management of asthma is a comprehensive approach that relies heavily on the expertise and dedication of healthcare professionals. It involves thorough assessment, accurate diagnosis, strategic planning, effective implementation, and diligent evaluation. By meticulously following this step-by-step process, healthcare professionals play a crucial role in providing the best possible care and treatment for patients with asthma, enhancing their overall health and well-being.
First, in...
First, in...
01:19Antiasthma Drugs: Leukotriene Modifiers
Leukotriene modifiers, or cysteinyl leukotriene receptor antagonists, are medications used to manage chronic asthma. These agents target specific inflammatory mediators produced during arachidonic acid metabolism, an essential process in generating inflammation in the body.
Leukotriene modifiers work through two distinct mechanisms:
Leukotriene modifiers work through two distinct mechanisms:
01:30Asthma-IV: Diagnostic and Management
The diagnosis and management of asthma are comprehensive, encompassing clinical assessments, lung function tests, and pharmacological interventions. Here's an overview:
Clinical Assessment for Asthma:
This is the first step in diagnosing and managing asthma. It includes:
Clinical Assessment for Asthma:
This is the first step in diagnosing and managing asthma. It includes:
01:28Asthma I: Introduction
Asthma is a chronic inflammatory disorder of the airways characterized by variable airflow obstruction and heightened bronchial responsiveness to a wide range of triggers. The underlying inflammation leads to airway swelling, mucus hypersecretion, and smooth muscle constriction, all of which narrow the airway lumen and impede airflow. Clinically, asthma presents with recurrent episodes of wheezing, shortness of breath, chest tightness, and coughing, symptoms that typically vary in intensity and...
01:24Asthma-III: Symptoms and Complications
Asthma, a common chronic respiratory condition, is classified considering the frequency and severity of symptoms alongside lung function impairment. Understanding this classification is essential for appropriate treatment and management. Here's a detailed look at the classification of asthma and its clinical features and complications:
Classification of Asthma
Classification of Asthma
01:13Asthma III: Clinical Manifestations
Asthma presents with a characteristic pattern of episodic respiratory symptoms that reflect underlying airway inflammation, bronchoconstriction, and mucus hypersecretion. Although severity varies among individuals, certain clinical manifestations are considered hallmarks of the disorder and often guide diagnosis and assessment.Respiratory SymptomsA persistent cough is one of the most common early features of asthma. It is frequently dry and tends to worsen at night or in the early morning,...